Republique Algerienne Democratique Et Populaire Ministere De L’Enseignement Superieur Et De La Recherche Scientifique Universite D’Oran

REPUBLIQUE ALGERIENNE DEMOCRATIQUE ET POPULAIRE MINISTERE DE L’ENSEIGNEMENT SUPERIEUR ET DE LA RECHERCHE SCIENTIFIQUE UNIVERSITE D’ORAN

FACULTE DES SCIENCES DEPARTEMENT DE BIOLOGIE THÈSE Présentée par Mme MARZOUG DOUNIAZED Pour obtenir LE DIPLOME DE DOCTORAT EN BIOLOGIE Spécialité : Sciences de l’Environnement Option : Parasitologie Marine

Intitulée :

BIODIVERSITY AND STRUCTURE OF PARASITE COMMUNITIES IN TWO COMMERCIAL FISH SPECIES FROM WESTERN MEDITERRANEAN COASTS OF ALGERIA

Les membres de jury :

Mr KHEROUA OMAR Professeur, Université d’Oran, Algérie (Président) Mr SCHOLZ TOMÁŠ Professeur, Institute of Parasitology, ASCR, Czech Republic (Examinateur) Mr KARA MOHAMED HICHEM Professeur, Université de Annaba, Algérie (Examinateur) Mme SENOUCI KHEIRA Maître de Conférences, Université d’Oran, Algérie (Examinateur) Mr BOUTIBA ZITOUNI Professeur, Université d’Oran, Algérie (Rapporteur) Mme KOSTADINOVA ANETA Dr, Institute of Parasitology, ASCR, Czech Republic (Co-Rapporteur)

2011/2012 TABLE OF CONTENTS

RÉSUMÉ i

ABSTRACT ii

LIST OF FIGURES iii

LIST OF TABLES v

REMERCIEMENTS vi

DÉDICACES vii

CHAPTER 1. General Introduction 1

CHAPTER 2. Aim and Objectives 11

CHAPTER 3. General Materials and Methods 12

CHAPTER 4. Descriptions of digeneans from Sardina pilchardus (Walbaum) (Clupeidae) off 17

the Algerian coast of the western Mediterranean, with a complete list of its

helminth parasites

CHAPTER 5. The parasite fauna of Boops boops 45

CHAPTER 6. Composition and structure of helminth communities in Sardina pilchardus 66

CHAPTER 7. Effects of fishing on parasitism in a sparid fish: Contrasts between two 74

areas of the Western Mediterranean

CHAPTER 8. Conclusions 94

REFERENCES 96

APPENDICES 106 RÉSUMÉ

Cette présente étude a été réalisée pour l’évaluation détaillée de la faune parasitaire de deux espèces poissons à caractère commercial, Sardina pilchardus et Boops boops. Ces derniers représentent une importante ressource biologique dans les réseaux trophiques marins et aussi pour la population humaine le long des côtes Méditerranéennes. Au total 10 échantillons comprenant 283 poissons (163 S. pilchardus et 120 B. boops) ont été collecté entre 2006 - 2007 du Golf d’Oran (Algérie). Au total 12 espèces de parasites ont été identifiées dans B. boops. La description morphologique a été détaillée et fournie pour quatre d’entre eux. S. pilchardus était infecté par 9 espèces ; En se basant sur ce matériel, cinq espèces de trematodes ont été d’écrits, dont un, Aphanurus virgula, représente un nouveau parasite enregistré chez cet hôte. Une liste complète des parasites de S. pilchardus dans son aire de distribution a été développée durant notre étude. Des informations ont été enregistrées sur 39 taxons avec 104 hôte-parasite- localité. Toutes les espèces parasites trouvées chez les deux hôtes sont enregistrés pour la première fois en Algérie. La thèse fournit des données sur les paramètres quantitatifs de l’infection parasitaire des deux hôtes dans le Golf d’Oran pour toutes les espèces. La composition, la structure et la diversité des communautés parasitaires dans S. pilchardus ont été décrit pour la première fois. Les analyses ne révèlent aucune corrélation significative entre la taille et l’abondance des parasites. Quatre espèces sont considérés communs, parmi eux, Pronoprymna ventricosa, Aphanurus stossichii et Hemiurus luehei étaient les plus prévalent dans quelques communautés. La communauté des parasites chez S. pilchardus était caractérisée par une faible richesse, abondance, diversité, similarité et une dominance élevée. Il n’existait aucun effet significatif de la saison ou échantillon sur la prévalence, l’abondance des parasites, et la structure de la communauté. La communauté parasitaire chez S. pilchardus du Golf d’Oran, est donc caractérisée par une homogénéité substantielle. L’impact de la pêche sur le taux du parasitisme a été examiné, en utilisant les communautés parasitaires chez B. boops. La prévalence, l’abondance des parasites, et la structure des communautés ont été comparé dans deux localités de la Méditerranée, La Baie de Santa Pola et le Golf d‘Oran, qui présentent un modèle opposé de la pêche de B. boops. Au total 29 espèces de parasites ont été identifiées, avec huit espèces communes aux deux localités. La composition des communautés parasitaires à Santa Pola était plus riche et abondante de ceux du Golf d’Oran et présente une structure différente de la communauté. Sur huit espèces communes utilisés dans la comparaison quantitatif, cinq reflètent une différence significatif pour la prévalence entre les deux localités, quatre d’entre eux avait une prévalence substantielle élevée à Santa Pola et juste une espèce était plus prévalente au Golf d’Oran. Deux trématodes spécialistes et un monogène généraliste des sparidés sont exposés à une prévalence et abondance élevée dans la Baie de Santa Pola. Ces différences cohérentes représentés dans la richesse, l’abondance, et la structure des infracommunautés de parasites chez B. boops dans les deux localités, peut refléter le contraste des modèles d’exploitation des deux populations de ce poisson hôte.

Mots clés : Biodiversité, Sardina pilchardus, Boops boops, faune parasitaires, prévalence, abondance, Infracomunauté, component communauté, Baie de Santa Pola, Golf d’Oran.

i ABSTRACT

The present study carried out a detailed assessment of the parasite fauna of two commercial species, Sardina pilchardus and Boops boops, which represent an important biological resource in marine food webs and for the human population along Mediterranean coasts. A total of 10 samples comprising 283 fish (163 S. pilchardus and 120 B. boops were collected in 2006-2007 from the Gulf of Oran (Algeria). A total of 12 parasite species was identified in B. boops; for four of them detailed morphological descriptions are provided. S. pilchardus was found to be infected with nine species. Five trematode species were redescribed based on this material of which one, Aphanurus virgula, represents new host record. A complete checklist of parasites of S. pilchardus throughout its distributional range, developed during the course of the study, comprises information for a total of 39 taxa and 104 host-parasite-locality records. All parasite species found in both hosts are recorded for the first time in Algeria. The thesis provides data on the quantitative parameters of infection of the two hosts in the Gulf of Oran for all species. The composition, structure and diversity of parasite communities in S. pilchardus were described for the first time. Analyses revealed no significant correlation between the fish size and parasite abundance. Four species were considered common. Of these, Pronoprymna ventricosa, Aphanurus stossichii and Hemiurus luehei were most prevalent in some communities. Parasite communities in S. pilchardus were characterised by low richness, abundance, diversity, similarity and high dominance. There were no significant effects on parasite prevalence and abundance and community structure of either season or sample. Parasite communities in S. pilchardus in the Gulf of Oran, therefore, were characterised by substantial homogeneity. The impacts of fishing on the rates of parasitism were examined using parasite communities in B. boops. Parasite prevalence, abundance and community structure were compared for two Mediterranean localities, Santa Pola Bay and the Gulf of Oran, that exhibit a contrasting pattern of fishing of B. boops. A total of 29 parasite species was identified, with eight species in common for the two localities. Parasite component communities at Santa Pola were more species rich and abundant than those at the Gulf of Oran and exhibited a different community structure. Of the eight common taxa used in the quantitative comparisons, five exhibited significant difference for prevalence between the two localities, four having substantially higher prevalence at Santa Pola and only one being more prevalent at the Gulf of Oran. Two specialist trematodes and a sparid generalist monogenean exhibited consistently higher prevalence and abundance at Santa Pola Bay. These consistent differences in the richness, abundance and structure of parasite infracommunities in B. boops from the two localities may reflect the contrasting patterns of exploitation of the populations of this fish host.

Keywords : Biodiversity, Sardina pilchardus, Boops boops, parasite fauna, prevalence, abundance, Infracomunauty, component communauty, Bay of Santa Pola, Gulf of Oran.

ii LIST OF FIGURES

CHAPTER 1 Page 1.1 Total marine fish landings compared to landings of Sardina pilchardus and Boops 2 boops in Algeria. 1.2 Distribution map of Sardina pilchardus. 3 1.3 Distribution map of Boops boops. 7

CHAPTER 3 3.1 Map showing sampling localities in the Gulf of Oran in Algeria (Sardina pilchardus 12 and Boops boops) and the Bay of Santa Pola in Spain (Boops boops).

CHAPTER 4 4.1 Parahemiurus merus ex Sardina pilchardus, ventro-lateral view, with uterus in outline. 43 4.2 Aphanurus stossichii ex Sardina pilchardus, ventro-lateral view, with uterus in outline. 43 4.3 Aphanurus virgula ex Sardina pilchardus, lateral view, with uterus in outline. 43 4.4 Lecithaster confusus ex Sardina pilchardus, ventral view, with uterus in outline. 44 4.5 Pronoprymna ventricosa ex Sardina pilchardus, two specimens, ventral view, with 44 uterus in outline.

CHAPTER 5 5.1 Bacciger israelensis ex Boops boops. Microphotograph of a specimen stained in toto. 46 5.2 Bacciger israelensis ex Boops boops. Line drawing, dorsal view with uterus in outline. 48 5.3 Aphanurus stossichii ex Boops boops. Line drawing, ventral view with uterus in 51 outline. 5.4 Aphanurus stossichii ex Boops boops. Microphotograph of a specimen stained in toto. 52 5.5 Hemiurus communis ex Boops boops. Line drawing, ventral view with uterus in 54 outline. 5.6 Lepocreadium album ex Boops boops. Microphotograph of a specimen stained in toto. 57 5.7 Lepocreadium album ex Boops boops. Line drawing, ventral view with uterus in 58 outline. 5.8 Tormopsolus sp. ex Boops boops. Microphotographs of specimens stained in toto 60 showing suckers (A) and eyespot pygment concentrations lateral to pharynx (B). 5.9 Tormopsolus sp. ex Boops boops. Microphotographs of A. Encysted metacercariae; B. 60 Excysted metacercariae in vivo. 5.10 Microphotographs of excysted metacercariae of Stephanostomum sp. (a) and 60 Prosorhynchus crucibulum (b, c) ex Boops boops in vivo. 5.11 Scolex pleuronectis ex Boops boops. Microphotographs of a specimen stained in toto. 62 5.12 Hysterothylacium aduncum ex Boops boops. Microphotographs of the anterior (A, B) 63 and posterior (C, D) extremities. 5.13 Ceratothoa oestroides ex Boops boops. 65

iii

CHAPTER 6 6.1 Box-plots for total length of Sardina pilchardus in the six samples from the Gulf of 66 Oran. 6.2 Box-plots for the richness and abundance of infracommunites in Sardina pilchardus in 69 the six samples from the Gulf of Oran. 6.3 Non-metric multidimentional scaling ordination of infracommunities in Sardina 71 pilchardus in the six samples from the Gulf of Oran. 6.4 Simulated distribution (blue bars, 999 randomisations) of the test statistic R under the 72 hypothesis of no seasonal differences between infracommunities.

CHAPTER 7 7.1 Landings of Boops boops registered (in tonnes) between 2007 and 2010 at the ports of 92 Oran in Algeria (red bars) and Santa Pola in Spain (blue bars). Inset: Total national landings of B. boops (in tonnes) of Algeria (red bars) and Spain (blue bars) for the period 2000-2008. 7.2 Prevalence of the eight parasite species in Boops boops common for the Bay of Santa 92 Pola and the Gulf of Oran. 7.3 Non-metric multidimentional scaling ordination of parasite component communities in 93 Boops boops (Bray-Curtis similarity based on abundance data) sampled at Santa Pola Bay (triangles) and Gulf of Oran (squares). 7.4 Graphical representation of Random Forest classification matrix for the parasite 93 infracommunities in Boops boops. NF, non-fished (Santa Pola Bay); F, fished (Gulf of Oran) populations

iv LIST OF TABLES

CHAPTER 1 Page 1.1 Total catches (in tonnes) of Boops boops and Sardina pilchardus at Oran. 2 1.2 Distribution of helminth parasites of Sardina pilchardus in the Mediterranean and 5 North East Atlantic. 1.3 Distribution of parasites of Boops boops in the Mediterranean and Atlantic Ocean after 9 Pérez-del-Olmo et al. (2007). CHAPTER 3 3.1 Number of fish examined, mean total (TL ± standard deviation, SD) and mean standard 14 fish length (SL ± SD) for the seasonal samples of the two fish hosts collected in the Gulf of Oran. CHAPTER 4 4.1 Comparative morphometric data for Parahemiurus merus. 35 4.2 Comparative morphometric data for Aphanurus stossichii. 36 4.3 Comparative morphometric data for Aphanurus virgula. 37 4.4 Comparative morphometric data for Lecithaster confusus. 38 4.5 Comparative morphometric data for Pronoprymna ventricosa. 39 4.6 Checklist of the helminth parasites of Sardina pilchardus. 40 CHAPTER 5 5.1 Comparative morphometric data for Bacciger israelensis. 47 5.2 Comparative morphometric data for Hemiurus communis. 53 5.3 Comparative morphometric data for Lepocreadium album. 59 CHAPTER 6 6.1 Prevalence (P%) and mean abundance (MA ± SD) of parasites of Sardina pilchardus in 68 the samples from the Gulf of Oran. 6.2 Infracommunity descriptors of helminth communities in Sardina pilchardus (mean ± 70 standard deviation) and significance of differences (p-values from K-W test; R of ANOSIM and p for similarity) between the samples. 6.3 Species that most contribute to the similarity (Bray-Curtis index) between 71 infracommunities in the samples of Sardina pilchardus. CHAPTER 7 7.1 Parasites in Boops boops at the Bay of Santa Pola and the Gulf of Oran. Prevalence (P 89 in %) and mean abundance (± standard deviation, SD) are given separately for the samples collected during the warm and cold seasons. P-values from contrasts in prevalence (Fischer's exact test) and abundance (GLM with factors locality and season and fish standard length as a covariate) are provided. 7.2 Results of generalized linear model on abundance of the common parasites and the 91 richness and abundance of parasite infracommunities in Boops boops at Santa Pola Bay and the Gulf of Oran.

v REMERCIEMENTS

Je souhaite présenter mes sincères remerciements à tous ceux qui m’ont aidé à élaborer cette thèse. Ces remerciements doublés de reconnaissance concernent particulièrement:

Mon encadreur, Mr Zitouni Boutiba, pour avoir suivi avec attention et dirigé d’une manière éclairée ma progression dans l’élaboration du sujet développée. Je tiens à lui adresser ma profonde reconnaissance, pour m’avoir toujours encouragé et soutenu dans les moments difficiles. Qu’il trouve ici l’expression de mon profond respect.

Mon Co-encadreur Mme Aneta Kostadinova, pour avoir au détriment de ses grandes préoccupations, assumé cette fonction, proposé un plan d’actualité qui compose cette thèse. Elle m’a dès le départ fait confiance, encouragée dans ma démarche pour la concrétisation de mon objectif. Je lui gré de son écoute, sa disponibilité et ses critiques constructives qui ont largement contribué à l’aboutissement de ce travail.

Mr Omar Kheroua pour avoir accepté la présidence de ce jury et que j’assure, en outre, de ma haute considération.

Mr Tomáš Scholz, qui en acceptant de juger ce travail, m’a fait un grand honneur. Qu’il trouve ici aussi mes vifs remerciements pour m’avoir ouvert toutes les portes de l’Institut de Parasitologie qu’il dirige à Ceske Budĕjovice.

Mr Mohamed Hichem Kara qui, en acceptant de juger mon travail, a fait preuve d’une bienveillance digne de ma profonde gratitude.

Mme Kheira Senouci pour avoir accepté d’examiner cette thèse et de faire partie du jury. Quelle trouve ici ma profonde reconnaissance de m’avoir initié et encouragé à aimer la Parasitologie. Je lui en suis très obligée.

Je tiens à remercier particulièrement Mlle Ana Pérez del Olmo, qui par son expérience dans ce domaine, a fait preuve d’une aide considérable et contribué de prés à l’aboutissement dse publication des articles de ce travail.

Mes vifs remerciements vont aussi à toute l’équipe de parasitologie de l’Académie des Sciences de Ceske Budĕjovice, Czech République, dirigé par le Professeur Tomáš Scholz. Je tiens à exprimer ma profonde gratitude au Professeur Juan Antonio Raga, qui m’a guidé dans le bon sens du chois scientifique ainsi qu’à toute son équipe.

Je remercie tous mes Collègue enseignants, techniciennes du Laboratoire Réseau de Surveillance Environnementale, Université d’Oran.

Je dédie ce travail à la mémoire de mes parents,

A mon cher mari Zulfiqar Ahmed Shaikh

A toute ma famille, et mes amis

vii CHAPTER ONE

GENERAL INTRODUCTION

1.1. SMALL PELAGIC AND DEMERSAL FISHERIES IN THE MEDITERRANEAN AND ALGERIA With approximately 17,000 animal species occurring in the Mediterranean Sea it ranks among the regions of high biodiversity and also among the best known in the world. The Mediterranean Sea is an important commercial fishing ground for nearly 900 fish species, about a 100 being commercially exploited. Some of these species have a high market value (Coll et al., 2010). Notably, Mediterranean Sea is one of the few marine areas of the world that shows steady increase in landings of fisheries for all major marine living resource groups, but especially for small pelagic fish such as sardines and sardinellas. These increases have been contributed to both, increased fishing pressure and increased nutrient levels providing more food for fishes (Caddy, 1997). Catches of small pelagic species and especially of Sardina pilchardus (Walbaum) and Engraulis encrasicolus (L.) in the Mediterranean represent an important part of total world fisheries catch (e.g. Freon & Misund, 1999). The two species are of high commercial importance and also the most exploited small pelagic fishes in the Mediterranean. One species of particular commercial interest in the countries of the southern and eastern Mediterranean coasts is the small demersal sparid Boops boops (L.) and this is in contrast to the countries of the northern Mediterranean coasts where, due to the low market demand, this species is not subjected to targeted fishery. Nevertheless, both, S. pilchardus and B. boops contribute substantially to the total income of the artisanal fisheries operating in close proximity to the home harbour in many countries. As a result, available data for northern African coasts (Southern Alboran Sea, Morrocan coast) indicate that stocks of B. boops are overexploited (stock status assessment for 2000-2009; GFCM (2011a) and those of S. pilchardus are fully exploited (stock status assessment for 2000-2009; GFCM (2011a) and GFCM (2011b), respectively). S. pilchardus and B. boops are among the most abundant and exploited species in the Algerian Mediterranean (Djabali et al., 1993; Kallianotis et al., 2000). This is associated with the traditional diet of the Mediterranean countries, that has been consistently shown to be associated with favourable health since marine fish species are important source of high- quality proteins, minerals and vitamin D as well as omega-3 fatty acids (Lloret, 2010).

1 The data presented in Fig. 1.1. illustrate that total marine fish landings in Algeria have increased from c. 90, 000 in 2000 to c. 160,000 tonnes in 2006, followed by a slight decrease afterwards. National landings of S. pilchardus that represent typically 40-50% of the totals, substantially contribute to the overall pattern. On the other hand, catches of B. boops show less variability, contributing to 3-5% of the national total landings.

Fig. 1.1. Total marine fish landings compared to landings of Sardina pilchardus and Boops boops in Algeria. Data (in tonnes) for the period 2000-2008. Sources: Ministère de la Pêche et des Ressources Halieutiques (2010) and FAO-GFCM Data Base (last accessed on 5.10.2011; http://www.gfcm.org/gfcm/topic/17105/en).

The two species constitute also important resource locally, at the Gulf of Oran. Table 1.1. presents the data on recent catches of S. pilchardus and B. boops at Oran. B. boops landings have increased by 47% in the last four years, whereas those of S. pilchardus show a marked decrease in 2008 (perhaps associated with a fishermen strike; personal observation) followed by a steady increase afterwards.

Table 1.1. Total catches (in tonnes) of Boops boops and Sardina pilchardus at Oran. Data source: Direction de la Pêche et des Ressources Halieutiques (DPRH, Oran).

Year S. pilchardus B. boops (tonnes) (tonnes) 2007 4,136 787 2008 331 869 2009 1,800 1,031 2010 3,117 1,157

Overall, these data indicating increased fishing may pose threats to populations of the two fish species both at global and local scales. Although it has been considered that these small-bodied short-lived fishes are relatively productive and resilient to current threats and pressures (e.g. Abdul Malak et al., 2011) due to their fast growing, early maturing and high fecundity, there threats cannot be ignored.

1.2. THE EUROPEAN PILCHARD, SARDINA PILCHARDUS: BIOLOGY AND PARASITES

The European pilchard ("sardine"), Sardina pilchardus (Teleostei; Clupeidae) is a small pelagic clupeid species distributed in North East Atlantic from the North Sea to Bay de Gorée (Senegal) and the Mediterranean basin. It is common in the western Mediterranean and Adriatic Sea and rare in the eastern Mediterranean and Black Sea (Fig. 1.2.; Froese & Pauly, 2011; Parrish et al., 1989). The gregarious S. pilchardus is among the most common and abundant fishes along the Algerian coasts of the western Mediterranean and the main target species of the purse seine artisanal fleet in the western Mediterranean (Lleonart & Maynou, 2003) and Algeria (Bedairia & Djebbar, 2009) .

Fig. 1.2. Distribution map of Sardina pilchardus. From Kathleen K. Reyes, AquaMaps in Froese & Pauly (2011).

S. pilchardus is pelagic-neritic oceanodromous fish, distributed at depths of 10-100 m, typically 25-100 m (Froeze & Pauly, 2011). This littoral species forms schools at depths of 25-100 during the day that rise to 10-35 m at night. S. pilchardus is not migratory but 3 performs restraint displacements from the offshore to the coast in spring and from the coast to the offshore at the end of autumn (Furnestin, 1943). In Algeria, purse-seine fisheries targeting sardines typically operates at depths of less than 60 m (e.g. Gulf of Annaba; Bedairia & Djebbar, 2009). S. pilchardus can reach a maximum of 27.5 cm in standard length but common standard length is 10-20 cm (Furnestin, 1943; Bouchereau, 1981; Mouhoub,1986; Stergiou & Karpouzi, 2002; Froeze &Pauly, 2011). It attains maturity at 14.8 cm total length and spawns in batches in autumn-winter (Abad & Giráldez, 1993). Along the Algerian coasts of the western Mediterranean (Gulf of Annaba) S. pilchardus attains sexual maturity at total length of 11.9 cm (age 19 months) for males and 12.6 cm (age 21 months) (Djabali et al., 1987). Spawning occurs between December and March according to Bedairia & Djebbar (2009) and from November to April according to Djabali et al. (1987). The biological annual cycle of S. pilchardus affects its catches, the yougest individuals recruiting to fishery schools in spring after migration from coastal to deeper areas (Bás et al., 1989). Spring and summer are sexually resting and intense feeding periods for adults when they grow and accumulate fat (Bandarra et al., 1997; Silva et al., 2008). Garrido et al. (2008) found a predominance of preys of <750 μm in sardine diet indicating that filter feeding is the dominant feeding mode. These authors also found similar feeding intensity for both sexes and for fish of different length classes. Main fishing is focused on the adults, between 16 and 19 cm. Like most clupeids, S. pilchardus is characterised by fast growth, early maturation (up to the second year of life) and relatively short life span (Silva et al., 2006). The maximum estimated age of S. pilchardus in the Mediterranean is six years corresponding to 19.4 cm from Bou-Ismail in Algiers (Mouhoub, 1986) and 22.3 cm from Galicia, Spain (Álvarez,

1980). In Algeria, the biology and the exploitation of sardine have been subject of several studies (Bouchereau, 1981; Brahmi et al., 1998). Djabali et al. (1987) have shown that the period of recruitment of S. pilchardus along Algerian coasts is during autumn (October) and estimated the mean size at recruitment as 10.1 cm (age 9 months). Bedairia & Djebbar (2009) estimated the size and average age of the stock in the Gulf of Annaba as 12.5 cm and 2.7 years. S. pilchardus has an intermediate trophic level of 3.1 (Stergiou & Karpouzi, 2002). Main predators, in addition to cetaceans, comprise Xiphias gladius, Merluccius merluccius, Seriola dumerili, Sarda sarda, Scomber scombrus, Thunnus thynnus, and Serranus cabrilla Stergiou & Karpouzi (2002). These authors have shown that S. pilchardus exhibits a typical

4 pelagic preying upon copepods, cladocerans, euphasiids, eggs, larvae, diatoms, and algae, and classified S. pilchardus as an omnivore with a preference for animals. Table 1.2. Distribution of helminth parasites of Sardina pilchardus in the Mediterranean and North East Atlantic. Numbers represent records in each area. Abbreviations: WM, Western Mediterranean; AD, Adriatic Sea; EM, Eastern Mediterranean; M, Mediterranean (area not specified); NEA, North East Atlantic.

Species WM AD EM M NEA

Monogenea Mazocraes alosae Hermann, 1782 2 1 Mazocraes pilchardi (van Beneden & Hesse, 1863) 1 2

Digenea Bacciger bacciger (Rudolphi, 1819) Nicoll, 1914 1 1 2 Pseudobacciger harengulae Yamaguti, 1939 2 Pronoprymna ventricosa (Rudolphi, 1819) Poche, 1926 2 Aphanurus stossichii (Monticelli, 1891) Looss, 1907 5 3 1 2 Hemiurus appendiculatus (Rudolphi,1802)† 1 Hemiurus luehei Odhner, 1905 1 2 1 5 Parahemiurus merus (Linton, 1910) Manter, 1940 2 Lecithaster confusus Odhner, 1905 1 Lecithaster gibbosus (Rudolphi, 1802) Lühe, 1901 2 1 Holorchis pycnoporus Stossich, 1901 1

Cestoda Bothriocephalus scorpii (Müller, 1776) (larva?) 1 Grillotia erinaceus (van Beneden, 1858) (larva) 1 Scolex pleuronectis Müller, 1788 (larva) 5 2

Nematoda Anisakis simplex (Rudolphi, 1809) sensu lato (larva) 2 1 1 1 Anisakis pegreffii Campana-Rouget & Biocca, 1955 (larva) 1 1 Contracaecum osculatum (Rudolphi, 1802) sensu lato (larva) 1 Contracaecum osculatum B (larva) 1 Hysterothylacium aduncum (Rudolphi, 1802) (larva) 4 4 1 2 1 Hysterothylacium fabri (Rudolphi, 1819) (larva) 1 1 Pseudoterranova decipiens (Krabbe, 1878) sensu lato (larva) 1

Acanthocephala Rhadinorhynchus lintoni Cable & Linderoth, 1963 1 Total records 26 15 6 8 21 † Probably a misidentification of Hemiurus luehei.

It is surprising that for a fish of such economic importance, there appear to have been only three studies reviewing the parasites of S. pilchardus. Monticelli (1887) documented four recorded helminth parasites including Aphanurus stossichii (Monthicelli, 1891) (as Distoma ocreatum (Rudolphi, 1802) and "Tetrabothrium" (probably Scolex pleuronectis). Baudouin (1905) mentioned only un-named trematodes and nematodes. Shukhgalter (1998) listed only 13 nominal species. It appears that most parasitological efforts have been focused on

5 Peroderma cylindricum Heller, 1865, a pathogenic copepod of the family Pennelidae Burmeister, 1835 (e.g. Raibaut et al., 1971; Ktari & Abdelmouleh, 1980; Ben Hassine et al., 1990; Ben Souissi & Ben Hassine, 1991; Becheikh et al., 1994, 1997; Belghyti et al., 1997) and larval nematode parasites (e.g. Tantawy & Mahmoud, 1999; Santos et al., 2006; Rello et al., 2008; see Chapter 4 for a detailed list of references), due to their potential threat to the fishery and to human health, respectively. However, the parasite fauna of S. pilchardus is poorly known. Existing data for identified to the species level helminth parasites in this host and their distribution in the Mediterranean and North East Atlantic are summarised in Table 1.2. The list comprises a total of 23 species [2 monogeneans, 10 digeneans, 3 cestodes (probably all larval), 7 larval nematodes and 1 acanthocephalan] and 76 host-parasite records. These reveal that more effort has been focused on fish from the Mediterranean basin. More than two-thirds of the records (55) result from studies in the Western (26) and Eastern (6) Mediterranean and the Adriatic Sea (15) and there were 8 further records from non-specified localities in the Mediterranean. Overall, three species have been most frequently recovered from S. pilchardus: the digeneans Aphanurus stossichii (Monticelli, 1891) and Hemiurus luehei Odhner, 1905, and the larval nematode Hysterothylacium aduncum (Rudolphi, 1802). Cestode larvae have also been frequently recorded under the collective name Scolex pleuronectis Müller, 1788. To my knowledge, there are no data on parasites of S. pilchardus in the southern waters of the western Mediterranean.

1.3. THE BOGUE, BOOPS BOOPS: BIOLOGY AND PARASITES

The bogue ("voupa"), Boops boops (L.) (Teleostei: Sparidae) is a gregarious, demersal to semipelagic species with a main distribution in the basins of the Mediterranean and North East Atlantic from Norway to Angola (Fig. 1.3.). It is also found in the Black Sea and in the Western Atlantic (Gulf of Mexico and Caribbean Sea) but is most common along the north African coasts, as well as the coasts of Spain, France, Italy and Greece (Whitehead et al., 1984; Demestre et al., 2000; Kallianiotis et al., 2000; Derbal & Kara, 2008). B. boops is among the most common and abundant fishes along the Algerian coasts of the western Mediterranean (Djabali et al., 1993; Derbal & Kara, 2008). Habitats of B. boops are located on the shelf of the coastal pelagic at a depth range 0- 350 m on various bottoms such as rocks, Posidonia beds, mud and sand (Bauchot & Hureau, 1986; García-Rubies & Zabala, 1990; Sánchez-Jerez et al., 2002; Valle et al., 2001, 2003). In the east of Algeria (Gulf of Annaba) B. boops is fished by demersal and pelagic trawling and 6 purse-seining at depths of 50-300 m but is also found in shallow waters, at soft bottoms and Posidonia beds (<10 m) (Derbal & Kara, 2001, 2008).

Fig. 1.3. Distribution map of Boops boops. From Kathleen K. Reyes, AquaMaps in Froese & Pauly (2011).

B. boops can reach a maximum 36 cm in total length but the usual range is 15-20 cm (Bauchot & Hureau, 1986). It is protogynous with an hermaphrodic stage occurring mostly in fish of 10-24.5 cm total length (Girardin, 1981; Erzini et al., 2001). Girardin (1981) has shown that bogue attains maturity at 13 cm total length (2 years-old) in the Gulf of Lion; its fecundity was found to increase exponentially afterwards. Spawning occurs between March and May depending on the latitude. The season affects the growth rates of B. boops. Thus increased temperature during the warm season stimulates bogue's nutrition, activity and finally the growth in length (Aoudjit, 2001). Along the Algerian coasts of the western Mediterranean B. boops is estimated to attain sexual maturity at 12 cm total length (males) and 13 cm (females) (Aoudjit, 2001). Spawning of bogue in this area occurs between January and May (Derbal & Kara, 2008). B. boops exhibits an intermediate trophic level: 2.5 for adults (Bell & Harmelin- Vivien, 1983); 2.97 for the larval stages (Sánchez-Velasco & Norbis, 1997); 2.53-3.30 (Stergiou & Karpouzi, 2002). These authors also considered that bogue attains its maximum trophic level early in the life span and reported no significant alteration of the trophic level with size/age (Stergiou & Karpouzi, 2002; Karpouzi & Stergiou, 2003). In addition to 7 cetaceans, main predators of B. boops are Seriola dumerili, S. rivoliana, Trachurus trachurus, T. mediterraneus, Merluccius merluccius, Phycis phycis, Sarda sarda, Scorpaena scrofa, Serranus cabrilla, S. hepatus, Sphyraena viridensis, Synodus saurus, Xiphias gladius and Zeus faber (Stergiou & Karpouzi, 2002; Froese & Pauly, 2011 and references therein). Data on feeding habits of B. boops are relatively scarce and somewhat ambiguous. Thus, Bell & Harmelin-Vivien (1983) considered it to be a microphagic carnivore but recorded that juveniles consume fairly large quantities of algae. On the other hand, Bauchot & Hureau (1986) considered that juveniles are mostly carnivorous and adults mostly herbivorous. Harmelin (1987) classified B. boops as planktophagus, Linde et al. (2004) as suction feeding secondary planktivores, Karpouzi & Stergiou (2003) as omnivores, and Stergiou & Karpouzi (2002) as omnivorous with a preference for plant material but also feeding on a wide range of invertebrates. Finally, Fernández et al. (2001) suggested that B. boops is mainly herbivorous whereas Ruitton et al. (2005) have shown that grazing on algae by bogue only occurs in the post-spawning period. The diet of B. boops has recently been studied in the Gulf of Annaba (eastern Algerian coasts) by Derbal & Kara (2008). They encountered a total of 1,780 preys belonging to 11 phyla and classified bogue as a voracious omnivore that feeds on benthic (Crustacea, Mollusca, Annelida, Sipuncula, Plantae) and pelagic preys (Siphonophorae, Copepoda, eggs), the algae (Chlorophyta) representing a considerable portion of bogue food. These authors also found no sex-associated differences and revealed significant changes in the diet in spring. Derbal & Kara (2008) concluded that, as in many regions of the Mediterranean, B. boops is an opportunistic predator that lacks preferential preys. The parasite fauna of B. boops is much better studied compared to that of S. pilchardus. In addition to a number of individual parasite records, large samples of fish have been studied in some localities in the Mediterranean (off Tunisia, Gulf of Lion, off Lebanese coasts; see Anato et al., 1991; Renaud et al., 1980; Saad-Fares, 1985). Recently, Pérez-del- Olmo et al. (2006, 2007) studied the biodiversity and geographical variations of parasite communities in B. boops along the Spanish coasts of the North Eeast Atlantic, and redescribed a number of digenean species that represented new host records including one species new to science: Wardula bartolii Pérez-del-Olmo, Gibson, Fernández, Sanisidro, Raga & Kostadinova, 2006; Lecithaster confusus Odhner, 1905; Aponurus laguncula Looss, 1907; Accacladium serpentulum Odhner, 1928); Robphildollfusium martinezgomezi López- Román, Gijón-Botella, Kim & Vilca-Choque, 1992; Magnibursatus caudofilamentosa (Reimer, 1971) Gibson & Køie, 1991; Lepocreadium album Stossich, 1890; Steringotrema pagelli (van Beneden, 1871) Odhner, 1911; Tetrochetus coryphaenae Yamaguti, 1934; and 8 the metacercaria of Stephanostomum euzeti Bartoli & Bray, 2004. Pérez-del-Olmo et al. (2007) also published a complete checklist of parasites of B. boops throughout its distributional range. A summary of the records for identified macroparasites of B. boops and their distribution in the Mediterranean and Atlantic regions is presented in Table 1.3. This includes a total of 56 species [6 monogeneans, 29 digeneans, 3 cestodes (all larval), 6 nematodes (5 larval), 4 acanthocephalans, 3 copepodes and 5 isopods] and 253 host-parasite records. A considerable part of the records (185) originates from the Mediterranean basin (compared to 68 records from the South East and North East Atlantic). Nearly half of the published records are from the western Mediterranean thus indicating that parasite fauna of B. boops is very rich in this area. The following six species have been most frequently recovered from this host: the digeneans Aphanurus stossichii (Monticelli, 1891) and Bacciger israelensis Fischthal, 1980, the monogeneans Microcotyle erythrini van Beneden & Hesse, 1863 and Cyclocotyla bellones Otto, 1821, the larval nematode Hysterothylacium aduncum (Rudolphi, 1802), and the isopod Ceratothoa parallela (Otto, 1828). To my knowledge, there are no data on parasites of B. boops from the Algerian coasts of the western Mediterranean.

Table 1.3. Distribution of parasites of Boops boops in the Mediterranean and Atlantic Ocean after Pérez-del-Olmo et al. (2007). Numbers represent records of the parasites identified to species level in each area. Abbreviations: WM, Western Mediterranean; EM, Eastern Mediterranean; M, Mediterranean (area not specified); NEA, North East Atlantic; SEA, South East Atlantic.

Species WM EM M NEA SEA Monogenea Cyclocotyla bellones Otto, 1821 11 2 4 Lamellodiscus elegans Bychowsky, 1957 3 Pseudaxine trachuri Parona & Perugia, 1889 3 3 1 Atrispinum salpae (Parona & Perugia, 1890) 2 1 Microcotyle erythrini van Beneden & Hesse, 1863 12 3 4 Microcotyle sargi Parona & Perugia, 1899 1 3 Digenea Stephanostomum bicoronatum (Stossich, 1883) (larva) 1 Stephanostomun cesticillum (Molin, 1858) (larva) 1 Stephanostomum euzeti Bartoli & Bray, 2004 (larva) 1 Stephanostomum imparispine (Linton, 1905) (larva) 2 Stephanostomum lophii Quinteiro et al., 1993 (larva) 1 Accacladium serpentulum Odhner, 1928 1 1 Tetrochetus coryphaenae Yamaguti, 1934 1 Prosorhynchus crucibulum Rudolphi, 1819 (larva) 1 1 Bacciger israelensis Fischthal, 1980 7 9 3 3 2 Monascus filiformis (Rudolphi, 1819) 1 Proctoeces maculatus (Looss, 1901) 3 Steringotrema pagelli (van Beneden, 1871) 2 1 9 Table 1.3. Continued.

Species WM EM M NEA SEA Tergestia acanthocephala (Stossich, 1887) 1 Aphanurus stossichii (Monticelli, 1891) 9 10 2 5 Hemiurus appendiculatus (Rudolphi, 1802) 2 1 Hemiurus communis Odhner, 1905 6 2 2 Lecithocladium excisum (Rudolphi, 1819) 3 2 2 2 Arnola microcirrus (Vlasenko, 1931) 2 1 Derogenes varicus (Muller, 1784) 3 1 Magnibursatus bartolii Kostadinova et al., 2003 2 Magnibursatus caudofilamentosa (Reimer, 1971) 1 Lecithaster confusus Odhner, 1905 1 Aponurus laguncula Looss, 1907 1 Lepocreadium album Stossich, 1890 2 1 Wardula bartolii Pérez-del Olmo et al., 2006 1 Robphildollfusium fractum (Rudolphi, 1819) 1 Robphildollfusium martinezgomezi López-Román et al., 1992 2 Cardiocephaloides longicollis (Rudolphi, 1819) (larva) 1 Zoogonus rubellus (Olsson, 1868) 1

Cestoda Heteronybelinia estigmena (Dollfus, 1960) (larva) 2 Nybelinia lingualis Cuvier, 1817 (larva) 1 Scolex pleuronectis Müller, 1788 (larva) 4 1 2 1

Nematoda Anisakis pegreffii Campana-Rouget & Biocca, 1955 (larva) 1 1 Anisakis simplex (Rudolphi, 1809) sensu lato (larva) 3 2 2 1 Hysterothylacium aduncum (Rudolphi, 1802) (larva) 6 5 1 Hysterothylacium fabri (Rudolphi, 1819) (larva) 4 Hysterothylacium rhacodes (Deardorff & Overstreet, 1978) 2 (larva) Pseudocapillaria adriatica (Nikolaeva & Naidenova, 1964) 3

Acanthocephala Rhadinorhynchus pristis (Rudolphi, 1802) 1 2 Rhadinorhynchus cadenati (Golvan & Houin, 1964) 1 Neoechinorhynchus agilis (Rudolphi, 1819) 1 Echinorhynchus gadi Zoega in Müller, 1776 1

Copepoda Naobranchia cygniformis (Hesse, 1863) 5 1 Lernaeolophus sultanus Nordmann, 1839 1 Peniculus fistula Nordmann, 1832 2 1

Isopoda Ceratothoa parallela (Otto, 1828) 9 3 1 Ceratothoa oestroides (Risso, 1826) 6 1 2 Ceratothoa oxyrrhynchaena Koelbel, 1878 1 Anilocra physodes (Linne, 1758) 5 1 Emetha audouini (Edwards, 1840) 1 Total records 111 55 19 53 15

10 CHAPTER TWO

AIM AND OBJECTIVES

2.1. AIM The study is aimed to identify the parasites in Sardina pilchardus and Boops boops, two commercial species which represent an important biological resource in marine food webs and for the human population along Mediterranean coasts, and to investigate the composition, structure and diversity of their parasite communities in the Gulf of Oran.

2.2. OBJECTIVES

• Identification of parasites on the basis of detailed studies on the morphology and taxonomy and description of the helminth fauna of S. pilchardus and B. boops in the study area.

• Obtaining baseline quantitative data on parasite communities in S. pilchardus and B. boops: species composition and quantitative parameters of infection.

• Description of the composition and structure of parasite communities in S. pilchardus. Evaluation of the effect of fish size and season of collection on the distribution of the most prevalent parasites and characterisation of the temporal variations in community composition and structure.

• Description and comparison of the composition and structure of parasite communities in B. boops from two areas with different fishing pressure, the Gulf of Oman and the Bay of Santa Pola (Spain).

11 CHAPTER THREE

GENERAL MATERIALS AND METHODS

3.1. STUDY AREA AND FISH SAMPLES

Both fish hosts (B. boops and S. pilchardus) were sampled at the Gulf of Oran on the Algerian western Mediterranean coast (Fig. 3.1.). The gulf of Oran is located between the industrial gulf of Arzew in the east and Andalouses coast in the west. It is delimited by Cape Aiguille in the east and by Cape Falcon in the west and is almost 30 miles wide (Boutiba, 1992; Kerfouf et al., 2007). The Gulf of Oran is supplied by waters originated from the North East Atlantic and comprises rich marine ecosystems that, unfortunately are very sensitive to the currently occurring global changes (pollution, overexploitation, climate change, and the introduction of non-indigenous species) resulting in environmental disturbance (CIRCE).

Santa Pola

Fig. 3.1. Map showing sampling localities in the Gulf of Oran in Algeria (red star: Sardina pilchardus and Boops boops) and the Bay of Santa Pola in Spain (blue star: Boops boops).

12 The benthic fauna of the Gulf of Oran is abundant and diverse including a number of species of bryozoans, sponges, annelids, polychets, crustaceans, cnidarians, molluscs and echinoderms (Boutiba, 1992). Of particular relevance to the present study is the study of Kerfouf et al. (2007) on the nature of the sediments and macrozoobenthic communities on the continental shelf of the Gulf of Oran. These authors revealed that these communities the area are characterised by lower diversity and abundance compared to other localities off the Algerian coast and Mediterranean (Spain, France) and identified five substrate types within the gulf with different richness of macrozoobenthos (4-18 spp.). Kerfouf et al. (2007) have shown that polychaetes represent the most diverse and abundant group, followed by crustaceans. Totals of 163 S. pilchardus and 120 B. boops were collected and examined for parasites in the Gulf of Oran during 2006-2008. Selective sampling was carried out in order to obtain representative samples of all seasons (see Table 3.1. for details on samples and fish size). These included six samples of S. pilchardus collected in 2006-2007 and four samples of B. boops collected in 2007-2008. Sample size ranged from 24 to 32 fish. The mean total length of S. pilchardus ranged from 14.3 to 16.1 cm (standard length range 12.0-13.5 cm) and the mean total length of B. boops ranged from 18.1-22.0 cm (standard length range 14.5-18.5 cm). Fish were transferred on ice to the laboratory, measured [total length (TL) and standard length (SL) in cm), weighed and assigned individual labels. Comparative materials used for contrasting the structure of parasite communities in B. boops under different fishing pressure conditions included five fish samples (a total of 140 fish) from the Bay of Santa Pola (Spain; Fig. 3.1.) dissected by Pérez-del-Olmo (2008). Details on these samples are presented in the Materials & Methods section of the manuscript (Chapter 7).

3. 2. PARASITE COLLECTION AND IDENTIFICATION

The samples of fishes were examined in the laboratory and all metazoan parasites were collected according a standard protocol. Some fishes were dissected fresh to collect live parasites and record details useful for their identification. Most of the fish were frozen for later analyses. Body surface and mouth were examined for ectoparasites. All organs were examined separately after dissection of the fish. Gills were soaked and scraped in saline solution. The intestinal tract (oesophagus, stomach, pyloric caeca and intestine) were also examined separately in saline solution. Internal organs (kidneys, hearth, liver and gonads) were compressed between glass plates. 13

Table 3.1. Number of fish examined, mean total (TL ± standard deviation, SD) and mean standard fish length (SL ± SD) for the seasonal samples of the two fish hosts collected in the Gulf of Oran.

Host Date of No. TL ± SD SL ± SD sampling of (cm) (cm) fish Sardina pilchardus 20.i.2006 20 14.3 ± 0.8 12.0 ± 0.8 15.iii.2006 29 16.1 ± 1.1 13.5 ± 1.0 8.vii.2006 32 14.8 ± 0.9 12.8 ± 1.0 10.iv.2007 29 15.0 ± 1.0 12.4 ± 0.8 30.vi.2007 29 14.9 ± 0.5 12.5 ± 0.6 30.ix.2007 24 15.0 ± 1.3 12.6 ± 1.3 163 Boops boops 10.v.2007 30 18.1 ± 2.8 14.6 ± 2.7 20.vii.2007 30 18.2 ± 2.4 14.5 ± 2.3 8.x.2007 30 22.0 ± 2.4 18.1 ± 1.9 10.ii.2008 30 21.3 ± 2.2 18.5 ± 2.2 120

All parasites were fixed and stored in 70% ethanol. Trematodes, cestodes and monogeneans were stained with iron acetocarmine according the protocol of Georgiev et al. (1986), dehydrated through an ethanol series, cleared with dimethyl phthalate, and mounted in Canada balsam. Nematodes were cleared for a few minutes in glycerine. Isopods were observed in saline solution. Measurements were taken from illustrations, made using a drawing apparatus at high magnification. All measurements presented in the thesis are in micrometres unless otherwise stated. All parasites were identified and counted (874 and 1,293 individuals in S. pilchardus and B. boops, respectively). Voucher material is deposited at the Natural History Museum, London, UK. The checklist of helminth parasites of S. pilchardus was compiled from an extensive search of literature sources and both the Host-Parasite Database (http://www.nhm.ac.uk/research-curation/projects/host-parasites/database/) and the Host-Parasite Catalogue compiled by the Natural History Museum, London.

14 3.3. TERMINOLOGY

Ecological terms used follow Bush et al. (1997). Prevalence (in per cent) is the proportion of the hosts in the sample infected with a particular species. Species with a prevalence of >30% will be further referred to as common, those with a prevalence of ≤30% as rare and those with prevalence < 10% as accidental; species with a prevalence > 50% are considered as most prevalent. Abundance is the number of individuals of a particular parasite in/on a single fish regardless of the fact if the fish is infected or not. Mean abundance is the sum of individuals of a particular species in a sample divided by the total number of the fish examined. Mean intensity is the sum of individuals of a particular species in a sample divided by the total number of infected fish. Community data were analysed at two hierarchical community levels: infracommunity (i.e. all parasites of different species within an indivividual fish) and component community (i.e. all parasites of all species in a fish sample).

3.5. STATISTICAL ANALYSES

Because of the aggregated distribution of the data, non-parametric tests [Spearman rank correlations (rs), Mann-Whitney (M-W) and Kruskall-Wallis (K-W) tests] were used in statistical comparisons. For multiple comparisons (post hoc tests following the main test) Bonferroni correction was applied for the significance levels. Where parametric tests were used, parasite abundance data were ln (x+1) transformed. Prevalences were compared with Fisher’s exact test. Analyses were carried out using Statistica 7.0 (StatSoft, Inc., Tulsa, OK, USA) and the programme Quantitative Parasitology (QP3.0, Rózsa et al., 2000).

The following indices were used in the description of communities (Krebs, 1989):

• Brillouin's diversity index

1 N! H = log ( ) N n ! n ! n ! .... 1 2 3 where N is the total number of individuals in the entire collection

n1 is the number of individuals belonging to species 1

n2 is the number of individuals belonging to species 2 (etc.)

15 • Berger-Parker' dominance index

Nmax BP = N

where Nmax is the number of individuals of the most abundant species in the collection N is the total sum of individuals in the collection

• Bray-Curtis similarity index

p Σ yij -yik i=1 S = 100 1- jk p Σ yij + yik i=1 represents the absolute value of the difference ׀...׀ where

yij, yjk represent the number of individuals of species i in each sample p is the number of species in samples

Analyses of parasite community composition were carried out with PRIMER v6 software (Clarke & Gorley, 2006), which provides a number of graphical and multivariate procedures for analyzing species/samples matrices. As an exploratory procedure the low-dimensional relationships between communities was first visualised by non-metric multi-dimensional scaling (MDS) ordination based on the similarity matrix (Bray-Curtis similarity based on square root transformed parasite abundance data; in some cases prevalence data were also used). As a second step, a one-way analysis of similarity (ANOSIM) was used to test the null hypothesis of no differences in parasite community structure due to season of collection or other factors. The ANOSIM test calculates the R-statistic, which indicates the degree of the difference between conditions (e.g. communities sampled in different seasons) and a significance level that corresponds to the alpha level (probability of Type I error) in traditional ANOVA. The R-statistics ranges from 0 to 1. Values for R > 0.75 indicate strong separation of community groupings due to considerable differences in the overall community structure. Values for R < 0.25 indicate little separation among community groupings. Intermediate values for R reflect some degree of overlap but generally different community structure (Clarke & Gorley, 2006). Similarity analyses were carried out using both infracommunities and component communities. Following the ANOSIM test, SIMPER test was carried out to identify the 'key discriminating' species on the basis of the overall percent contribution of each species to the average dissimilarity of communities between conditions.

16 CHAPTER FOUR

Descriptions of digeneans from Sardina pilchardus (Walbaum) (Clupeidae) off the Algerian coast of the western Mediterranean, with a complete list of its helminth parasites

Douniazed Marzoug * Zitouni Boutiba * David I. Gibson * Ana Pérez-del- Olmo * Aneta Kostadinova

Submitted 23 July, 2011 / Accepted 11 September, 2011 Systematic Parasitology (2011)

D. Marzoug Z. Boutiba Laboratoire Réseau de Surveillance Environnementale, Département de Biologie, Université d'Oran, 31000 Oran, Algeria

D. I. Gibson Department of Zoology, Natural History Museum, Cromwell Road, London, SW7 5BD, UK

A. Pérez-del-Olmo Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain. XRAq (Generalitat de Catalunya)

A. Kostadinova Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 České Budějovice, Czech Republic e-mail: [email protected]; [email protected]

Abstract Five species of digeneans parasitic in the pilchard Sardina pilchardus (Walbaum), a little studied host, from off the Algerian coast of the western Mediterranean are redescribed. These are Parahemiurus merus (Linton, 1910) Manter, 1940, Aphanurus stossichii (Monticelli, 1891) Looss, 1907, Aphanurus virgula Looss, 1907, Lecithaster confusus Odhner, 1905 and Pronoprymna ventricosa (Rudolphi, 1819) Poche, 1926. One of these, A. virgula, is a new record for this host. One other digenean, Hemiurus luehei Odhner, 1905, was also recorded from this host. A complete checklist of the helminth parasites of S. pilchardus throughout its distributional range, comprising 104 host-parasite records of 39 taxa, is presented.

Introduction

The pilchard Sardina pilchardus (Walbaum) is an important food-fish in the Mediterranean and the North-East Atlantic regions. Although some parasitological efforts have been focused on a pathogenic copepod and larval nematode parasites, due to their potential threat to the fishery and to human health, respectively, its parasite fauna is poorly known. In a study of the biodiversity of parasite communities associated with this clupeid in the western Mediterranean off Oran, Algeria, we found nine helminth species, including five digeneans whose morphology is poorly known, especially in the Mediterranean region. One of these has not been previously reported from this host. A sixth digenean, Hemiurus luehei Odhner, 1905, was also recorded during the course of the study (see Appendix), but this material was not suitable for description. This study provides morphological descriptions of the five species and includes a checklist of the helminth parasites of S. pilchardus throughout its range.

Materials and methods

A total of 163 Sardina pilchardus was examined from the western Mediterranean coast of Algeria off Oran. Comparative material of Aphanurus stossichii (Monticelli, 1891) was also collected from the sparid Boops boops (L.) at the same locality. The trematodes were acquired from fresh fish, fixed by being pipetted into nearly boiling saline, stained with iron acetocarmine, dehydrated through a graded alcohol series, cleared in dimethyl phthalate and examined as permanent mounts in Canada balsam. Voucher material is deposited in the

18 British Museum (Natural History) Collection at the Natural History Museum, London, UK (BMNH). Measurements were taken from illustrations made using a drawing tube at high magnification and are in micrometres.

Family Hemiuridae Looss, 1899 Subfamily Hemiurinae Looss, 1899 Genus Parahemiurus Vaz & Pereira, 1899

Parahemiurus merus (Linton, 1910) Manter, 1940

Material studied Ex Sardina pilchardus (Walbaum), Perciformes, Clupeidae. Stomach. Western Mediterranean: off Oran, Algeria. BMNH 2011.7.7.1.

Description (Fig. 1; Table 1)

[Based on 4 whole-mounted adult specimens. Ranges for measurements given in Table 1.] Body large, with fusiform hindbody, widest at level of ovary/vitellarium, and short (9-10 % of body length), tapered forebody (Fig. 1). Ecsoma well developed (withdrawn in 1 specimen). Tegument thick, with well-expressed plications; latter extend posteriorly on ventral surface to just anterior to ovary, on dorsal surface to mid-way between ventral sucker and seminal vesicle. Pre-oral lobe distinct. Oral sucker subterminal, spherical. Ventral sucker large, muscular, subspherical, nearly twice size of oral sucker (sucker-width ratio 1:1.89–2.18). Prepharynx absent. Pharynx muscular, elongate-oval to subglobular, overlaps posterior margin of oral sucker dorsally. Oesophagus very short or apparently absent. ‘Drüsenmagen’ distinct. Caeca thick-walled, terminate blindly at about mid-level of extended ecsoma. Testes 2, elongate-oval to subglobular, oblique, in anterior half of hindbody; anterior testis overlaps posterior region of seminal vesicle ventrally. Seminal vesicle large, saccular, elongate-oval, well separated from ventral sucker (by 203-247), with thick wall (9-17). Pars prostatica very long, convoluted, lined with anuclear 'blebs'; main bulk of prostatic cells between ventral sucker and seminal vesicle. Sinus-sac elongate, cylindrical, with rather thick walls, slightly overlaps ventral sucker dorsally. Hermaphroditic duct short, cylindrical. Genital atrium not observed. Genital pore a wide median slit just posterior to aperture of oral

19 sucker, at 29–131 from anterior extremity. Sinus-organ protruding through genital pore observed in single specimen (Fig. 1). Ovary transversely-oval, post-testicular, median, well separated from posterior testis, contiguous with vitellarium. Mehlis’ gland posterior to vitelline masses. Juel's organ not seen, probably obscured by uterine coils. Uterine seminal receptacle voluminous, dorsal to vitellarium. Uterus extensive in hindbody; main bulk between seminal vesicle and vitellarium; loops reach posteriorly into extended ecsoma. Metraterm very short, enters sinus-sac ventrally to male duct. Eggs numerous, small, operculate. Vitellarium well developed, ventral, just posterior to ovary; in 2 irregular to slightly indented masses. Excretory pore terminal; other details of excretory system not observed.

Remarks

Bray (1990) revised Parahemiurus Vas & Pereira, 1930, discussed the variability of the major morphological characters used for species distinction within the genus, and provided a redescription of the type-species, P. merus, and a key to the seven species he considered valid. The specimens from S. pilchardus key down to and agree well morphologically with Bray's (1990) redescription of P. merus based on material from various host species (Table 1), but differ in the larger dimensions (above the range provided for P. merus) of the suckers and pharynx (Table 1), the higher upper limit for testicular length (168-226 vs 152-170 µm) and the lower upper limits for the relative length of the forebody (10 vs 19% of body length) and sucker-width ratio (2.18 vs 2.58). Furthermore, the seminal vesicle in the present material is consistently well posterior to the posterior border of the ventral sucker [203-247 µm vs overlapping or just posterior (up to 170 µm) to ventral sucker] and the genital pore is located more posteriorly (upper limit for the distance between the genital pore and the anterior extremity of the body 131 vs 70 µm). In view of its apparent variation and wide distribution (Bray, 1990), one might suspect the existence of a species complex, but, in our view and in the absence of a molecular study, such a suggestion is premature. Bray (1990) considered P. sardiniae Yamaguti, 1934 a synonym of P. merus, a synonymy with which we agree, and listed three records of the former species from S. pilchardus, two from the Mediterranean (Nikolaeva, 1966; Nikolaeva & Parukhin, 1969) and one thought to be from the Red Sea (Parukhin, 1975); the latter ‘record’ is a misinterpretation due to the confusing locality data in Parukhin (1975). Our study, therefore, provides the third record of P. merus in S. pilchardus and the first description from this host.

Subfamily Aphanurinae Skrjabin&Guschanskaja, 1954 Genus Aphanurus Looss, 1907

Aphanurus stossichii (Monticelli, 1891) Looss, 1907

Material studied Ex Sardina pilchardus (Walbaum), Perciformes, Clupeidae. Stomach. Western Mediterranean: off Oran, Algeria. BMNH 2011.7.7.2-4.

Comparative material studied Ex Boops boops (L.), Perciformes, Sparidae. Stomach. Western Mediterranean: off Oran, Algeria. BMNH 2011.7.7.5.

Description (Fig. 2; Table 2)

[Based on 15 whole-mounted adult specimens ex S. pilchardus and B. boops. Ranges and means for measurements given in Table 2.] Body plump, subcylindrical, tapered anteriorly, widest at level of gonads or vitellarium. Ecsoma absent. Tegument thick, plicated both ventrally and dorsally along entire length of body. Forebody short, 14.9–21.5% of body length. Pre-oral lobe distinct. Oral sucker spherical, subterminal. Ventral sucker muscular, spherical, much larger than oral sucker. Prepharynx absent. Pharynx elongate-oval to subglobular. Oesophagus apparently absent. Caeca wide, thick-walled, form small ‘Drüsenmagen’ just posterior to pharynx, reach fairly close to posterior extremity. Testes transverse-oval, large, larger than or similar in size to ovary, oblique, contiguous or slightly separated, slightly anterior to mid-hindbody. Seminal vesicle large, subspherical to elongate-oval, thick-walled, just anterior to or overlapping anterior testis dorsally, at 50-114 from posterior margin of ventral sucker (4.5-10.3% of body length). Pars prostatica tubular, long, with wide lumen and thick wall, enveloped by several layers of large gland-cells (main bulk between anterior testis and ventral sucker). Sinus-sac tubular, narrow. Hermaphroditic duct tubular, straight, lined by small tubercles; its distal half is eversible, forming temporary sinus-organ. Genital pore median, at mid-level of or immediately posterior to oral sucker. Ovary post-testicular, fairly close to or contiguous with posterior testis, transversely oval. Juel’s organ and Laurer’s canal not seen. Uterine seminal receptacle present, dorsal to

21 vitellarium. Uterine coils reach well posterior to vitellarium. Eggs operculate, thin-shelled, small in relation to size of body. Vitellarium a single large, compact mass, distinctly larger than, posterior to and contiguous with ovary, in third quarter of hindbody (post-vitelline region 23.5–36.4% of body length). Excretory pore terminal; details of excretory system not observed, but lateral arms unite dorsally to pharynx.

Remarks

This is the first detailed description of A. stossichii from its type-host, S. pilchardus, although it has been listed in a number of faunistic studies of this host (Table 6). Monticelli (1887) initially identified, as Distoma ocreatum (Rudolphi, 1802), worms he found in S. pilchardus and Sardinella aurita (Valenciennes) from off Naples; later, he (Monticelli, 1891) described this material under the name Apoblema stossichi Monticelli, 1891 but did not provide measurements. He differentiated this species from most other species of Apoblema Dujardin, 1845 (syn. of Hemiurus Rudolphi, 1809; see Gibson, 2002) on the basis of its small ecsoma, plicated tegument, single vitelline mass and more posterior position of the genital pore. Looss (1907) found this species in Lichia amia (L.), Boops boops (L.), Spicara maena (L.) and Trachurus mediterraneus (Steindachner) off Trieste and noted a different location of the genital pore, i.e. posterior to the intestinal bifurcation in Monticelli's description versus at the level of the oral sucker in his material, but concluded that both are conspecific. The only existing brief description, including material from Sardina pilchardus, is based on composite material [i.e. ex S. pilchardus, Scomber scombrus L., Boops boops and Pagellus erythrinus (L.); see Paradižnik & Radujković (2007)]. This species has, however, recently been redescribed from Boops boops from various localities in the North East Atlantic region (off Spain), the Mediterranean Sea (off Spain and Turkey) and the Black Sea (off Bulgaria) (Kostadinova et al., 2004). The present material from S. pilchardus and the comparative material from B. boops at the same Algerian locality (off Oran) agree well morphologically with the data of Kostadinova et al. (2004). However, both sets of specimens examined by us had larger bodies and gonads; egg-length also varied below the lower range recorded by these authors in the specimens from B. boops in the North East Atlantic (20-27 and 22-27, respectively vs 26-32 µm; Table 2).

22 Aphanurus virgula Looss, 1907

Material studied

Ex Sardina pilchardus (Walbaum), Perciformes, Clupeidae. Stomach. Western Mediterranean: off Oran, Algeria. BMNH 2011.7.7.6.

Description (Fig. 3; Table 3)

[Based on single whole-mounted adult specimen. Measurements given in Table 3.] Body small, subcylindrical, widest at levels of ventral sucker and vitellarium. Ecsoma absent. Tegument thin, with faint plications. Forebody short, 18.4% of body length. Pre-oral lobe absent. Oral sucker subspherical; aperture almost terminal. Ventral sucker muscular, rounded. Prepharynx absent. Pharynx elongate-oval. Oesophagus very short. ‘Drüsenmagen’ indistinct. Caeca wide, thick-walled, reach close to posterior extremity. Testes oblique, contiguous; anterior testis elongate-oval; posterior testis subglobular. Seminal vesicle similar in size to testes, elongate-oval, thin-walled, just anterior to anterior testis, at 102 from ventral sucker. Pars prostatica tubular, long, enveloped by several layers of large gland-cells (main bulk between seminal vesicle and ventral sucker), joins base of sinus- sac. Sinus-sac tubular, long (c.12% of body length and c.65% of length of forebody), reaches level of ventral sucker dorsally. Genital pore median, at mid-pharyngeal level. Ovary post-testicular, somewhat separated from posterior testis, transverse-oval. Mehlis' gland small, diffuse, dorsal to vitellarium. Uterine seminal receptacle and Juel’s organ not seen. Uterine coils reach close to posterior extremity of body, enter base of sinus-sac ventrally to male duct. Eggs operculate, thin-shelled, large in relation to size of body (Fig. 3); mean size 23 × 9. Vitellarium a single post-ovarian mass, contiguous with ovary, fairly close to posterior extremity (post-vitelline region 12.1% of body length), large, distinctly larger than ovary. Excretory pore terminal; other details of excretory system not seen.

Remarks

The specimen described above was the only one clearly identifiable as this species, and suitable for morphological study, found among specimens of Aphanurus from S. pilchardus. Nevertheless, we provide its description, in order to indicate that S. pilchardus in the

23 Mediterranean hosts both local species of Aphanurus. Comparison with the metrical data from the redescription of A. virgula by Kostadinova et al. (2004) shows that this specimen has somewhat larger measurements for body and forebody length and for body width at the level of the ventral sucker and forebody. Furthermore, the vitellarium is wider and more posteriorly located (VIT/BL 12.1 vs 16.1-33.6%) and the seminal vesicle is also wider and located further posterior to the ventral sucker (VS-SV/BL 12.6 vs 3.3-8.8%) (Table 3). The eggs in this fully-gravid, mature specimen are less numerous than those in A. stossichii and larger in relation to the size of the body. This relationship, the smaller size of the body and a sinus-sac reaching to the level of the ventral sucker, all appear to serve as distinguishing features for A. virgula (see Looss, 1907; Kostadinova et al., 2004). S. pilchardus is a new host record of A. virgula and this is the first record of this species from the western Mediterranean.

Family Lecithasteridae Odhner, 1905 Genus Lecithaster Lühe, 1901

Lecithaster confusus Odhner, 1905

Material studied Ex Sardina pilchardus (Walbaum), Perciformes, Clupeidae. Stomach. Western Mediterranean: off Oran, Algeria. BMNH 2011.7.7.7.

Description (Fig. 4; Table 4)

[Based on 3 whole-mounted adult specimens. Ranges for measurements given in Table 4.] Body elongate-fusiform, widest at posterior margin of ventral sucker. Tegument smooth. Pre- oral lobe small to distinct. Oral sucker subterminal, subspherical. Ventral sucker large, muscular, subspherical, mostly in anterior half of body. Sucker-width ratio 1:1.62–1.69. Forebody c.20% of body length. Prepharynx absent. Pharynx globular, large. Oesophagus apparently absent, ‘Drüsenmagen’ distinct. Caeca wide, terminate fairly close to posterior extremity. Testes subspherical, subsymmetrical to slightly oblique, contiguous or separated; anterior testis just posterior to ventral sucker. Seminal vesicle saccular, elongate-oval, overlaps anterior testis dorsally, reaches to mid-level of ventral sucker anteriorly. Pars

24 prostatica long; prostatic cell field rather wide; prostatic cells large. Sinus-sac short. Genital pore opens close to level of posterior pharynx. Ovary tetra-lobed; lobes broad. Blind seminal receptacle large, dorsal to testes and ovarian lobes. Uterine coils reach posterior to vitellarium and close to posterior extremity. Eggs 16-18 × 9-11. Vitellarium consists of 6 tear-shaped lobes, arranged radially. Post- vitelline region 14.4–18.7% of body length. Excretory pore terminal; other details of excretory system not seen.

Remarks

The studied specimens agree well with the descriptions of L. confusus given by Odhner (1905) and Looss (1908) with the exception of the somewhat smaller sucker-width ratio (1:1.62–1.69 vs 1:1.75 and 1:2.0, respectively) and the shorter post-vitelline region (14-19% of body length vs 26% calculated from Looss; Table 4). Comparison with a recent description from an accidental host (B. boops) given by Pérez-del Olmo et al. (2006) revealed that specimens from S. pilchardus possess a distinctly larger body and organ sizes, possibly suggesting a better development in a more suitable host; however, the numbers of specimens upon which this comment is based is small. L. confusus has previously been recorded in S. pilchardus from the NE Atlantic (Shukhgalter, 1998).

Family Faustulidae Poche, 1926 Subfamily Baccigerinae Yamaguti, 1958 Genus Pronoprymna Poche, 1926

Pronoprymna ventricosa (Rudolphi, 1819) Poche, 1926

Material studied Ex Sardina pilchardus (Walbaum), Perciformes, Clupeidae. Pyloric caeca. Western Mediterranean: off Oran, Algeria. BMNH 2011.7.7.8-10.

Description (Fig. 5; Table 5)

[Based on 15 whole-mounted adult specimens. Ranges for measurements given in Table 5.] Body fusiform, flattened in dorso-ventral plane, with maximum width at level of gonads.

25 Tegument thin, typically smooth but very fine spines covering entire body observed in single specimen. Parenchymal gland-cells present in 2 lateral groups between levels of pharynx and ventral sucker. Forebody 20−37% of body length. Oral sucker subspherical, subterminal. Prepharynx not seen. Pharynx elongate-oval to globular. Oesophagus distinctly longer than pharynx; intestinal bifurcation close to ventral sucker. Caeca cylindrical, lined with glandular cells, end blindly at level of testes or more anteriorly. Testes 2, symmetrical, elongate-oval to subglobular, in anterior half of hindbody. Cirrus-sac thin-walled, elongate-oval, dorsal to ventral sucker. Seminal vesicle internal, bipartite; anterior part distinctly smaller, 23-53 × 20-53 vs 44-149 × 29-73 (means 39 × 34 vs 95 × 50). Pars prostatica indistinct, short; prostatic cells few. Genital atrium present but indistinct in ventral view. Genital pore median, just anterior to ventral sucker. Ovary median, usually tri-lobed (4 lobes observed in 5 specimens). Small elongate- oval canalicular seminal receptacle posterior to ovary observed in 2 specimens; Laurer's canal not seen. Uterus occupies most of hindbody. Eggs operculate, abundant, small, 22-27 × 13-16. Vitellarium in form of 2 large, symmetrical, elongate-oval, compact groups of follicles, just posterior to ventral sucker, overlaps testes ventrally; collecting ducts wide, unite to form distinct reservoir ventral to mid-level of testes. Excretory pore terminal; other details of excretory system not observed.

Remarks

The present description agrees well with the redescription of P. ventricosa given by Bray & Gibson (1980). The size ranges for the body, oral and ventral suckers, pharynx, cirrus-sac and testes extend below the known range for specimens from Alosa spp. (Table 5) and this may reflect host-induced variation. P. ventricosa is considered a relatively common parasite of shads (Alosa spp.) and is also found in other clupeiforms, such as the sprat Sprattus sprattus (L.) and the anchovy Engraulis encrasicolus (L.) (see Bray & Gibson, 1980, for details). Other host records published after the revision by Bray & Gibson (1980) include: Clupeonella spp. [Clupeonella engrauliformis (Borodin); C. grimmi Kessler; and C. cultriventris (Nordmann) (see Ghayoumi et al., 2009)]; Clupea harengus L. (see Campbell et al., 2007); Alosa fallax Lacépède (see Cetindag, 1993; Quilichini et al., 2007; Aprahamian, 1985); and A. caspia persica (Iljin) (see Kornijchuk & Barzegar, 2005; Youssefi et al., 2011). This is only the third record of P. ventricosa from S. pilchardus and the third from the western Mediterranean [previously listed

26 as Pentagramma symmetricum (Stossich, 1899) Chulkova, 1939 by Parukhin et al. (1971) and Parukhin (1976)].

Checklist of the helminth parasites of Sardina pilchardus

Surprisingly, for a fish of such economic importance, there appear to have been only three studies reviewing the parasites of Sardina pilchardus. The first, Monticelli (1887) documents four recorded helminth parasites, whereas Baudouin (1905) mentions only un-named trematodes and nematodes as helminth parasites. The third, Shukhgalter (1998), lists only 13 nominal species. A comprehensive list of the helminth parasites of this fish is therefore presented in Table 6. This includes a total of 39 taxa [two monogeneans, 16 digeneans, four cestodes (probably all larval), 15 larval nematodes and two acanthocephalans] and 104 host- parasite records. Of these, 24 taxa have been identified to the species level; more than two- thirds of the current records (70) result from studies in the Mediterranean. The prevalence and mean abundance data for the helminths recovered in the present study are given in the Appendix. Records by Parukhin (1975) for five species [the larval cestodes Grillotia erinaceus (van Beneden, 1858), Nybelinia sp. and Scolex pleuronectis Müller, 1788; the larval trematode Stephanostomum imparispine (Linton, 1905); and the acanthocephalan Rhadinorhynchus pristis (Rudolphi, 1802) Lühe, 1911] parasitising S. pilchardus from the South Atlantic are not included in the checklist, since this host species does not occur there. It is possible that the South American pilchard Sardinops sagax (Jenyns) was examined instead by Parukhin.

Acknowledgements This study was supported by Institute of Parasitology (Academy of Sciences of the Czech Republic) grants Z60220518 and LC522 and the Grant Agency of the Czech Republic grant P505/10/1562 to AK, and by Laboratoire Réseau de Surveillance Environnementale, Département de Biologie, Université d'Oran grant CNEPRU: F01820060065. Dr Stefano D’Amelio, Sapienza University of Rome, kindly translated some Italian text.

27 References

Aprahamian, M. W. (1985). The effect of the migration of Alosa fallax fallax (Lacepède) into fresh water, on branchial and gut parasites. Journal of Fish Biology, 27, 521–532. Barbagallo, P., & Drago, U. (1903). Primo contributo allo studio della fauna elminthologica dei pesci della Sicilia Orientale. Archives de Parasitologie, 7, 408-427. Baudouin, M. (1905). Les parasites de la sardine. Revue Scientifique, 3 (23), 715-722. Beneden, P. J. van, & Hesse, C. E. (1863) Récherches sur les bdellodes ou hirduinés et les trématodes marines. Mémoires de l'Academie Royale de Belgique, 34, 1-142. Bray, R. A. (1990) A review of the genus Parahemiurus Vaz & Pereira, 1930 (Digenea: Hemiuridae). Systematic Parasitology, 15, 1-21. Bray, R. A., & Gibson, D. I. (1980). The Fellodistomidae (Digenea) of fishes from the northeast Atlantic. Bulletin of the British Museum (Natural History), Zoology series, 37, 199-293. Campbell, N., Cross, M. A., Chubb, J. C., Cunningham, C. O., Hatfield, E. M. C., & MacKenzie, K. (2007). Spatial and temporal variations in parasite prevalence and infracommunity structure in herring (Clupea harengus L.) caught to the west of the British Isles and in the North and Baltic Seas: implications for fisheries science. Journal of Helminthology, 81, 137-146. Carvalo-Varela, M., & Cunha-Ferreira, V. (1984). Larva migrans visceral por Anisakis e outros ascarideos: helmintozoonoses potenciais por consumo de peixes marinhos em Portugal. Revista Portuguesa de Ciencias Veterinarias, 79, 299-309. Cetindag, M. (1993). Pronoprymna ventricosa (Rudolphi, 1819), a new digenic [sic] Trematoda from the Alosa fallax caught from the Black Sea in Turkey. Ankara Universitesi Veteriner Fakultesi Dergisi, 40, 311-317 (In Turkish). Cordero del Campilo, M., et al. (1975). Indice-catálogo de zooparásitos ibéricos. II. Trematodos. Barcelona: Consejo Superior de Investigaciones Científicas, pp. 75-117. Dimitrov, G. I., Bray, R. A., & Gibson, D. I. (1999). A redescription of Pseudobacciger harengulae (Yamaguti, 1938) (Digenea: Faustulidae) from Sprattus sprattus phalericus (Risso) and Engraulis encrasicholus ponticus Alexandrov off the Bulgarian Black Sea coast, with a review of the genus Pseudobacciger Nahhas & Cable, 1964. Systematic Parasitology, 43, 133-146. Fioravanti, M. L, Zamperetti, S., Minelli, C., Restani, R., & Sigovini, G. (1996). Distribution of Anisakidae larvae in marine fish from the Northern Adriatic Sea. EMOP VII Abstracts. Parassitologia, 38, 34.

28 Gaevskaya, A. V. (1996). [New records of trematodes from eastern Atlantic fishes.] Parazitologiya, 30, 504-509 (In Russian). Ghayoumi, R., Malek, M., Jamili, S., Nabavi, M., & Motallebi, A. (2009). Epizootiology of intestinal helminth parasites of Clupeonella spp. (Osteichthyes: Clupeidae) from the Caspian Sea, Iran. Bulletin of the European Association of Fish Pathologists, 29, 109- 117. Gibson, D. I. (2002). Family Hemiuridae Looss, 1899. In: Gibson, D. I., Jones, A., & Bray, R. A. (Eds) Keys to the Trematoda. Vol. 1. Wallingford: CAB International, pp. 305-340. Gibson, D. I., & Bray, R. A. (1986). The Hemiuridae (Digenea) of fishes from the north-east Atlantic. Bulletin of the British Museum (Natural History), Zoology series, 51, 1-125. Kijewska, A., Dzido, J., Shukhgalter, O., & Rokicki, J. (2009). Anisakid parasites of fishes

caught on the African Shelf. Journal of Parasitology, 95, 639-645 Kornijchuk, J. M., & Barzegar, M. (2005). Pronoprymna ventricosa (Rud., 1819) - a parasite of the Caspian clupeids. Mors'kiy Ekologichniy Zhurnal, 1, 45-47 (In Russian). Kostadinova, A., Gibson, D. I., Balbuena, J. A., Power, A. M., Montero, F. E., Aydogdu, A., & Raga, J. A. (2004). Redescriptions of Aphanurus stossichii (Monticelli, 1891) and A. virgula Looss, 1907 (Digenea: Hemiuridae). Systematic Parasitology, 58, 175-184. Larizza, A., & Vovlas, N. (1995). Morphological observations on third-stage larvae of Anisakis simplex A (Anisakidae: Nematoda) from Adriatic and Ionian waters. Journal of the Helminthological Society of Washington, 62, 260-264. Looss, A. (1907). Zur Kenntnis der Distomenfamilie Hemiuridae. Zoologischer Anzeiger, 31, 585-620. Looss, A. (1908). Beitrage zur Systematik der Distomen. Zur Kenntnis der Familie Hemiuridae. Zoologische Jahrbücher (Systematik), 26, 63-180. Monticelli, F. S. (1887). Note elmintologiche: Sul nutrimento e sui parassiti della Sardina Clupea pilchardus C. V. del Golfo di Napoli. Bollettino del Società di Naturalisti in Napoli, 1, 85-88. Monticelli, F. S. (1891). Osservazioni intorno ad alcune forme del gen. Apoblema Dujardin. Atti della Reale Accademia della Scienze, Torino, 26, 496–524. Nicoll, W. (1914). The trematode parasites of fishes from the English Channel. Journal of the Marine Biological Association of the United Kingdom, 10, 466-505. Nikolaeva, V. M. (1964). [A preliminary note on the parasite fauna of fishes from eastern Mediterranean.] Trudy Sevastopol’skoi Biologicheskoi Stantsii, 15, 348-362 (In Russian).

29 Nikolaeva, V. M. (1966). [Trematodes of the suborder Hemiurata infecting fish in the Mediterranean Basin.] In: Delyamure, S. L. (Ed.) [Helminth fauna of animals in southern seas.] Kiev: Naukova Dumka, pp. 52-66 (In Russian). Nikolaeva, V. M., & Naidenova, N. N. (1964). [Nematodes of pelagic and benthopelagic fish of seas of the Mediterranean basin.] Trudy Sevastopol’skoi Biologicheskoi Stantsii, 17, 125-158 (In Russian). Nikolaeva, V. M., & Parukhin, A. M. (1969). [Trematode fauna of fish in the Mediterranean Sea.] In: Problemy Parazitologii. Trudy VI Nauchnoi Konferentsii Parazitologov USSR. Kiev: Naukova Dumka, pp. 259-162 (In Russian). Odhner, T. (1905). Die Trematoden des arktischen Gebietes. Fauna Arctica, 4, 289-372. Oğuz, M. C., Güre, H., Özdemır, H., Öztürk, M. O., & Savas, Y. (2000) A study of Anisakis simplex (Rudolphi 1809) in some economically important teleost fish caught on the Canakkale coast and throughout the Dardanelles Strait. Türkiye Parazitoloji Dergisi, 24, 431-434 (In Turkish). Orecchia, P., & Paggi, L. (1978). Aspetti di sistematica e di ecologia degli elminti parassiti di pesci marini studiati presso l’Istituto di Parassitologia dell’Università di Roma. Parassitologia, 20, 73–89. Papoutsoglou, S. E. (1976). Metazoan parasites of fishes from Saronicos Gulf, Athens - Greece. Thalassographica, 1, 69-102. Paradižnik, V. (1987). Aphanurus stossichi (Monticelli, 1891) Looss, 1907, from the pilchard, Sardina pilchardus (Risso) from the Gulf of Koper. Zbornik Biotehniske Fakultete Univerze Edvarda Kardelja v Ljubljani, 24, 175-176 (In Serbian). Paradižnik, V., & Radujković, B. (2007). Digenean trematodes in fish of the North Adriatic Sea. Acta Adriatica, 48, 115-129. Parukhin, A. M. (1968). [Helminthofauna of fishes of South Atlantic.] Biologiya Morya, Kiev, 14, 96-113 (In Russian). Parukhin, A. M. (1975). [Specific features in helminthofauna of Clupeiformes of the South Seas.] Trudy Biologo-Pochvennogo Instituta, Vlaldivostok (Novaja Serija), 26, 143- 151 (In Russian). Parukhin, A. M. (1976). [Parasitic worms in food fishes of the Southern Seas.] Kiev: Naukova Dumka, 183 pp. (In Russian). Parukhin, A. M., Naidenova, N. N., & Nikolaeva, V. M. (1971). The parasite fauna of fishes caught in the Mediterranean Sea. In: Vodjanichkiy, V.A. (Ed.) [Expeditionary investigations in the Mediterranean Sea in May-July 1970.] Kiev: Naukova Dumka, pp. 64-87 (In Russian).

30 Pérez-del Olmo, A., Gibson, D. I., Fernández, M., Sanisidro, O., Raga, J. A., & Kostadinova, A. (2006). Descriptions of Wardula bartolii n. sp. (Digenea: Mesometridae) and three newly recorded accidental parasites of Boops boops L. (Sparidae) in the NE Atlantic. Systematic Parasitology, 63, 97–107. Petter, A. J. (1969). Enquête sur les nématodes des sardines pêchées dans la région nantaise. Rapport possible avec les granulomes éosinophiles observés chez l'homme dans la region. Annales de Parasitologie Humaine et Comparée, 44, 25-36. Petter, A. J., & Maillard, C. (1988). Larves d'Ascarides parasites de poissons en Méditerranée occidentale. Bulletin du Muséum National d'Histoire Naturelle, Serie 4, 10, 347-369. Petter, A. J., & Radujkovic, B. M. (1989). Parasites des poissons marins du Monténégro: Nematodes. Acta Adriatica, 30, 195-236. Pouchet, G., & de Guerne, J. (1887). Sur la nourriture de la sardine. Comptes Rendus Hebdomadaire des Séances de l’Académie des Sciences, Paris, 104, 712-715. Quilichini, Y., Foata, J., & Marchand, B. (2007). Ultrastructural study of the spermatozoon of Pronoprymna ventricosa (Digenea, Baccigerinae), parasite of the twaite shad Alosa fallax (Lacepède) (Pisces, Teleostei). Parasitology Research, 101, 1125-1130. Radujkovic, B. M., & Raibaut, A. (1989). Parasites des poissons marins du Monténégro: liste des espèces de poissons avec leurs parasites. Acta Adriatica, 30, 307-320. Rego, A. A. (1987). Identificaçao de helmintes de peixes da costa continental portuguesa. Garcia de Orta, Serie de Zoologia, 12, 113-116. Reichenbach-Klinke, H.-H. (1957a). Artzugehörigkeit und Entwicklung der als Scolex pleuronectis Müller bekannten Cestodenlarvan (Cestoidea, Tetraphyllidea). Verhandlungen der Deutschen Zoologischen Gesellschaft, 1956, 317-324. Reichenbach-Klinke, H.-H. (1957b). Vorläufige Mitteilung über die Parasitenfauna der Fische des Golfs von Neapel. Pubblicazioni della Stazione Zoologica di Napoli, 30, 115-126. Reichenbach-Klinke, H.-H. (1958). Les parasites de la sardine (Sardina pilchardus Walb.) et de l’anchois (Engraulis encrasicholus Rond.). Rapport. Commission Internationale pour la Mer Méditerranée, 14, 351-353. Rello, F. J., Adroher, F. J., & Valero, A. (2008). Hysterothylacium aduncum, the only anisakid parasite of sardines (Sardina pilchardus) from the southern and eastern coasts of Spain. Parasitology Research, 104, 117-121. Rioja, E. (1923). Notas sobre algunos trematodes parasitos del digestivo de los clupéidos. Boletín de la Real Sociedad Española de Historia Natural, 23, 87-91. Ruiz-Valero, J., Valero, A., Adroher, F. J., & Ortega, J. E. (1992). Presencia de ascáridos en peces comerciales de frecuente consumo en Granada. In: Hernández, S. (Ed.) “In

31 memoriam” al Prof. Doctor D. F. de P. Martínez-Gómez. Córdoba: Universidad de Córdoba, pp. 335-349. Santos, A. T., Sasal, P., Verneau, O., & Lenfant, P. (2006). A method to detect the parasitic nematodes from the family Anisakidae, in Sardina pilchardus, using specific primers of 18 S DNA gene. European Food Research and Technology, 222, 71-77. Sey, O. (1970a). Parasitic helminths occurring in Adriatic fishes. Part. II. (Flukes and tapeworms). Acta Adriatica, 13(6), 3-15. Sey, O. (1970b). Parasitic helminths occurring in Adriatic fishes. Part 3. (Nematodes, Acanthocephala). Acta Adriatica, 13(7), 3-16. Shukhgalter, O. A. (1998). [General characteristics of parasitofauna of European sardine (Sardina pilchardus Walb.) and some aspects of its geographical variability.] In: Fishery biological researches by AtlantNIRO in 1996-1997. Trudy Atlanticheskii Nauchno-Issledovatel’skii Institut, Rybnogo Khozyaitsva i Okeanografii, Kaliningrad, pp. 170-180 (In Russian). Shukhgalter, О. А., & Rodjuk, G. N. (2007) The use of parasitological data in population studies of the commercial pelagic fishes from the Central-East Atlantic. ICES Annual Science Conference, Helsinki, 2007. Stock identification - applications for aquaculture and fisheries management. ICES CM 2007/L:13, 5 pp. Silva, M. E. R., & Eiras, J. C. ( 2003). Occurrence of Anisakis sp. in fishes off the Portuguese west coast and evaluation of its zoonotic potential. Bulletin of the European Association of Fish Pathologists, 23, 13-17. Sprehn, C. (1933). Trematoda. In: Grimpe, G., & Wagler, E. (Eds) Die Tierwelt der Nord- und Ostsee, 4, 1-60. Stossich, M. (1883). Brani di Elmintologia Tergestina. Serie prima. Bolletino della Società Adriatica di Scienze Naturali in Trieste, 8, 112-121. Stossich, M. (1887). Brani di elmintologia tergestina. Serie quarta. Bolletino della Società Adriatica di Scienzi Naturali in Trieste, 10, 90-96. Tantawy, E. A., & Mahmoud, N. A. M. (1999) Some studies on larval nematodes (Ascarididae) infection in Sardina pilchardus with reference to its public health importance. Egyptian Journal of Agricultural Research, 77, 1371-1384. Timon-David, J. (1953). Sur un metacercaire de la sardine et ses affinités avec to le groups Rhodometopa. Compte Rendu de l’Academie des Sciences, Paris, 237, 1182-1184. Viu, M., Sánchez-Acedo, C., Del Cacho, E., Quílez, Z., & López-Bernad, F. (1996). Occurrence of anisakid larvae (Nematoda: Ascaridida) in fresh market fish from Zaragoza (Spain). Research and Reviews in Parasitology, 56, 25-28.

32 Youssefi, M. R., Hosseinifard, S. M., Halajian, A., Amiri, M. N., & Shokrolahi, S. (2011). Pronoprymna ventricosa (Digenea: Faustulidae) in Alosa caspia fish in north of Iran. World Journal of Fish and Marine Sciences, 3, 104-106.

Appendix

Collection data for the material collected from Sardina pilchardus off the coast of Algeria during the present study. Abbreviations: P, prevalence (%); MA, mean abundance.

Pronoprymna ventricosa (Rudolphi, 1819): 20.i.2006 (P=35.0%; MA=1.05); 15.iii.2006 (P=55.2%; MA=1.41); 8.vii.2006 (P=50.0%; MA=1.19); 10.iv.2007 (P=55.2%; MA=1.93); 30.vi.2007 (P=65.5%; MA=1.86); 30.ix.2007 (P=83.3%; MA=2.63). Aphanurus stossichii (Monticelli, 1891): 20.i.2006 (P=25.0%; MA=0.60); 15.iii.2006 (P=44.8%; MA=0.66); 8.vii.2006 (P=46.9%; MA=1.06); 10.iv.2007 (P=34.5%; MA=0.62); 30.vi.2007 (P=34.5%; MA=0.55); 30.ix.2007 (P=58.3%; MA=0.92). Aphanurus virgula Looss, 1907: 20.i.2006 (P=5.0%; MA=0. 05). Hemiurus luehei Odhner, 1905: 20.i.2006 (P=45.0%; MA=0.70); 15.iii.2006 (P=37.9%; MA=0.72); 8.vii.2006 (P=50.0%; MA=1.31); 10.iv.2007 (P=31.0%; MA=0.55); 30.vi.2007 (P=31.0%; MA=0.69); 30.ix.2007 (P=33.3; MA=0.46). Parahemiurus merus (Linton, 1910): 20.i.2006 (P=25.0%; MA=0.40); 15.iii.2006 (P=34.5%; MA=0.66); 8.vii.2006 (P=37.5%; MA=0.66); 10.iv.2007 (P=24.1%; MA=0.38); 30.vi.2007 (P=24.1%; MA=0.34); 30.ix.2007 (P=45.8%; MA=0.92). Lecithaster confusus Odhner, 1905: 20.i.2006 (P=5.0%; MA=0.05); 8.vii.2006 (P=15.6%; MA=0.16). Scolex pleuronectis Müller, 1788 (larval cestode): 20.i.2006 (P=30.0%; MA=1.35); 15.iii.2006 (P=24.1%; MA=1.28); 8.vii.2006 (P=40.6%; MA=1.88); 10.iv.2007 (P=17.2%; MA=1.03); 30.vi.2007 (P=27.6%; MA=1.38); 30.ix.2007 (P=37.5%; MA=2.42). Hysterothylacium aduncum (Rudolphi, 1802) (larval nematode): 20.i.2006 (P=15.0%; MA=0.15); 15.iii.2006 (P=13.8%; MA=0.21); 8.vii.2006 (P=3.1%; MA=0.03); 10.iv.2007 (P=6.9%; MA=0.17); 30.vi.2007 (P=6.9%; MA=0.07). Anisakis sp. (larval nematode): 20.i.2006 (P=20.0%; MA=0.30); 15.iii.2006 (P=20.7%; MA=0.52); 8.vii.2006 (P=15.6%; MA=0.38); 10.iv.2007 (P=10.3%; MA=0.17); 30.vi.2007 (P=13.8%; MA=0.17).

33 Figure legends

Figs. 1-3 1. Parahemiurus merus (Linton, 1910) ex Sardina pilchardus, ventro-lateral view, with uterus in outline; 2. Aphanurus stossichii (Monticelli, 1891) ex Sardina pilchardus, ventro-lateral view, with uterus in outline; 3. Aphanurus virgula Looss, 1907 ex Sardina pilchardus, lateral view, with uterus in outline. Scale-bars: 1, 500 µm; 2,3, 300 µm.

Figs. 4-5 4. Lecithaster confusus Odhner, 1905 ex Sardina pilchardus, ventral view, with uterus in outline; 5. Pronoprymna ventricosa (Rudolphi, 1819) ex Sardina pilchardus, two specimens, ventral view, with uterus in outline. Scale-bars: 500 µm.

34 Table 1 Comparative morphometric data for Parahemiurus merus (Linton, 1910).

Source Present study (n=3) Bray (1990) Host Sardina pilchardus Various hosts Body length 2,630–2,971 800–2,990 Forebody length 243–292 – Soma length 1,685–2,475 – Ecsoma length 496–945 up to 1,020 Body width at level of ventral 325–394 – sucker Maximum body width 551–657 210–570 Pre-oral lobe length 15–20 8–50 Oral sucker 95–142 × 98–151 36–83 × 51–82 Pharynx 61–103 × 55–87 32–64 × 32–51 Ventral sucker 197–258 × 214–293 101–170 × 124–170 Sinus-sac 145–183 × 29–44 95-220 × ? Pars prostatica length 867–1,453 – Prostatic cells (field width) 191–261 – Seminal vesicle 180–202 × 81–127 48–278 × 41–130 Wall of seminal vesicle 9-17 – Anterior testis 136–168 × 98–203 40–152 × 68–145 Posterior testis 131–226 × 130–177 48–170 × 64–170 Ovary 113–133 × 199–223 47–234 × 80–233 Mehlis' gland 101 × 121 – Vitelline masses 157–220 × 130–197 – Eggs 23–24 × 11 20–32 × ? Ventral sucker to seminal vesicle 203–247 up to 170 Genital pore to anterior extremity 29–131 13–70 Forebody/Body length (%) 9–10 6–19 Sucker-width ratio 1:1.89–2.18 1:1.76–2.58

35 Table 2 Comparative morphometric data for Aphanurus stossichii (Monticelli, 1891).

Source Present study Kostadinova et al. (2004) Host Sardina pilchardus Boops boops B. boops B. boops B. boops Locality Mediterranean Mediterranean Black Sea Mediterranean NE Atlantic (off Oran, Algeria) (off Oran, Algeria) (off Bulgaria) (off Turkey) (off Spain) Range Mean Range Mean Range Range Range Body length 1,040–1,402 1,195 999–1,329 1,148 667–901 771–1,209 897–1,376 Forebody length 172–263 218 169–239 215 92–192 158–225 175–254 Body width at ventral sucker 175–277 217 199–269 228 163–175 150–217 221–300 Body max. width in hindbody 220–388 283 234–388 299 204–275 183–317 271–384 Pre-oral lobe length 7–22 13 9–20 14 – – – Oral sucker 55–70 × 55–73 63 × 65 41–76 × 50–82 67 × 71 47–55 × 53–60 51–66 × 53–72 58–68 × 58–70 Pharynx 41–55 × 35–50 49 × 42 47–58 × 35–58 52 × 47 36–88 × 30–38 36–49 × 30–47 40–51 × 36–47 Ventral sucker 110–146 × 110–161 129 × 131 131–187 × 131–181 161 × 158 109–132 × 128–143 104–155 × 104–145 121–168 × 128–160 Sinus-sac 111–140 × 20–38 125 × 27 117–166 × 20–32 144 × 26 63–107 × 17–23 85–170 × 17–19 104–192 × 13–28 Prostatic cells (field width) 156–234 197 61–175 118 46–104 72–130 85–125 Seminal vesicle 88–190 × 82–111 125 × 92 105–237 × 64–155 149 × 96 62–155 × 68–107 70–149 × 43–111 104–145 × 70–115 Wall of seminal vesicle 9–15 – 6–22 – 4–13 3–11 2–9 Right testis 61–131 × 51–166 93 × 120 44–91 × 58–126 60 × 81 43–72 × 55–113 47–96 × 51–132 38–60 × 62–92 Left testis 58–117 × 85–178 88 × 123 41–131 × 37–111 67 × 78 36–70 × 64–94 43–79 × 58–121 51–89 × 70–92 Ovary 64–131 × 105–169 85 × 145 44–102 × 105–165 68 × 132 53–79 × 70–141 51–79 × 64–128 43–75 × 68–124 Vitellarium 102–207 × 128–190 137 × 163 70–146 × 105–210 92 × 159 60–92 × 111–153 53–145 × 92–181 49–107 × 89–166 Eggs 20–27 × 8–12 24 × 10 22–27 × 8–14 24 × 11 23–28 × 9–13 19–26 × 9–12 26–32 × 9–11 Ventral sucker to seminal 50–114 90 70–181 119 21–104 38–204 67–146 vesicle Post-vitelline region 245–456 343 277–420 331 200–242 158–334 263–459 FO/BL (%) 14.9–21.5 18.3 17.0–21.4 18.7 11.0–23.9 15.9–23.0 16.1–22.3 VS-SV/BL (%) 4.5–10.3 7.8 6.4–15.5 10.3 2.7–13.3 4.2–18.8 6.8–10.6 VIT/BL (%) 23.5–36.4 28.6 22.2–33.4 28.5 23.2–32.5 19.1–29.7 26.5–38.2 SSL/BL (%) 10.0–11.5 10.5 10.7–15.9 12.1 7.8–15.6 7.4–16.9 10.7–14.5 SSL/FO (%) 50.0–69.5 58.0 53.3–91.9 65.4 43.2–78.2 39.2–81.3 49.8–81.4

Abbreviations: FO/BL, forebody length as a proportion of body length; VS-SV/BL, distance from ventral sucker to seminal vesicle as a proportion of body length; VIT/BL, post- vitelline field length as a proportion of body length; SSL/BL, length of sinus-sac as a proportion of body length; SSL/FO, length of sinus-sac as a proportion of forebody length.

Table 3 Comparative morphometric data for Aphanurus virgula Looss, 1907.

Source Present study Kostadinova et al. (2004) Host Sardina pilchardus Engraulis encrasicolus Locality Mediterranean Black Sea (off Oran, Algeria) (off Bulgaria) n=1 Range (Mean) Body length 814 400−596 (473) Forebody length 150 62−108 (92) Body width at ventral sucker 143 64−125 (81) Body max. width in hindbody 139 75−138 (98) Oral sucker 33 × 42 26−49 (33) × 26−43 (31) Pharynx 27 × 24 19−38 (24) × 15−38 (20) Ventral sucker 97 × ? 47−96 (63) × 47−87 (61) Sinus-sac 97 × 15 77−96 (83) × 6−17 (9) Pars prostatica length 119 58−104 (74) Prostatic cells (field width) 37 21−40 (26) Seminal vesicle 66 × 51 19−60 (36) × 15−36 (23) Wall of seminal vesicle < 2 < 2 Right testis 59 × 75 19−62 (34) × 23−45 (35) Left testis 53 × 53 23−53 (34) × 21−70 (38) Ovary 62 × 75 19−66 (35) × 30−72 (41) Vitellarium 92 × 126 38−87 (53) × 47−100 (63) Eggs 22−24 × 9−10 (23 × 9) 20−23 × 9−13 (22 × 11) Ventral sucker to seminal vesicle 102 13−46 (29) Post-vitelline region 99 96−188 (117) FO/BL (%) 18.4 15.3−21.8 (19.6) VS-SV/BL (%) 12.6 3.3−8.8 (6.0) VIT/BL (%) 12.1 16.1−33.6 (24.8) SSL/BL (%) 11.9 12.9−21.3 (17.9) SSL/FO (%) 64.7 71.3−100 (87.7)

Abbreviations: FO/BL, forebody length as a proportion of body length; VS-SV/BL, distance from ventral sucker to seminal vesicle as a proportion of body length; VIT/BL, post-vitelline field length as a proportion of body length; SSL/BL, length of sinus-sac as a proportion of body length; SSL/FO, length of sinus-sac as a proportion of forebody length.

Table 4 Comparative morphometric data for Lecithaster confusus Odhner, 1905.

Source Present study Odhner (1905) Looss (1908) Pérez-del Olmo et al. (2006) Host Sardina pilchardus Clupea Alosa agone Boops boops harengus (syn. A. finta) Range Range Range Range Body length 657–1,037 1,000–1,500 1,000–1,200 469–515 Body width at ventral sucker 423–438 300–500 400 117–146 Forebody length 137–274 – – 162–179 Pre-oral lobe 9–32 – – 8–10 Oral sucker 105–134 × 117–164 ? × 130–160 ? × 140–150 58–75 × 54–72 Pharynx 70–85 × 67–82 ? × 70–85 – 35 × 30 Ventral sucker 210–251 × 190–277 ? × 230–300 ? × 250–270 82–96 × 85–96 Sinus-sac 73 × 31 80–110 × ? – 48 × 14–19 Seminal vesicle 140 × 67 – – 64–88 × 29–40 Pars prostatica length 264–350 – – 48–128 Pars prostatica field width 123 – – 16–43 Right testis 85–104 × 93–96 – – 43–51 × 45–46 Left testis 82–123 × 91–128 – – 50 × 40 Ovary 131–146 × 140–184 – – 48–83 × 40–58 Seminal receptacle 193 × 73 – – 24 × 42 Vitelline field 111–120 × 91–152 ? × 250 – 74–77 × 56–74 Eggs 16-18 × 9-11 15–17 × 7 15–17 × 9 18–19 × 10–12 Sucker-width ratio 1:1.62–1.69 1:1.75 1:2.0 1:1.33–1.57 Forebody as % of length 20.9 – 22.9* 34.5–34.8 Post-vitelline region as % of 14.4–18.7 – 26.0* 7.8–13.6 length *Calculated from the published drawing.

38 Table 5 Comparative morphometric data for Pronoprymna ventricosa (Rudolphi, 1819).

Source Present study Gaevskaya (in Bray & Gibson (1980) litt.)* Locality Mediterranean (off Oran) Black Sea River Severn & off Celtic Sea Scarborough, UK Host Sardina pilchardus Alosa pontica Alosa fallax Alosa alosa (?) Range Mean ± SD Range Range Range Body length 807−1,621 1,192 ± 237 1,020−1,560 1,240−1,800 1,300−1,660 Forebody length 228−488 358 ± 79 − − − Body width 233−436 324 ± 67 340−360 400−740 510−670 Oral sucker length 93−140 117 ± 15 130−150 110−200 120−170 Oral sucker width 88−155 126 ± 20 150-160 140−170 140−180 Ventral sucker length 93−184 134 ± 28 180−200 130−230 150−250 Ventral sucker width 111−204 145 ± 27 180−200 140−240 170−230 Pharynx length 44−70 56 ± 8 59 50−80 70−100 Pharynx width 32−58 47 ± 8 51 50−77 60−70 Oesophagus length 88−263 158 ± 47 46-59 60−150 100−130 Cirrus-sac length 99−225 147 ± 40 − 180−250 140−230 Cirrus-sac width 32−76 55 ± 14 − 50−70 50−70 Vitelline masses length 105−196 152 ± 24 − − − Vitelline masses width 55−123 86 ± 17 − − − Testes length 96−257 163 ± 41 110−160 170−220 200−290 Testes width 82−161 114 ± 21 81−120 100−170 170−210 Ovary length 79−210 140 ± 39 160 − − Ovary width 91−178 128 ± 26 120-150 − − Seminal receptacle 55-73 × 23-35 − − − − Egg-length 22-27 24 ± 2 27 23−33 27−30 Egg-width 13-16 14 ± 1 14 16−18 16−18 Forebody/Body length (%) 20−37 30 ± 4 30 24−30 25−27 Sucker-width ratio 1:0.89−1.40 1:0.88 ± 0.1 1:1.5 1:0.90−1.30 1:1.02−1.20 *Bray & Gibson (1980) Table 6 Checklist of the helminth parasites of Sardina pilchardus. Abbreviations: AD, Adriatic Sea; EM, Eastern Mediterranean; M, Mediterranean; NEA, North East Atlantic; RS, Red Sea; WM, Western Mediterranean.

Parasite Area Reference Monogenea Mazocraeidae Price, 1936 Mazocraes alosae Hermann, 1782 WM Parukhin et al. (1971) WM Parukhin (1976) NEA Shukhgalter (1998) Mazocraes pilchardi (van Beneden & Hesse, NEA van Beneden & Hesse (1863) (as Octocotyle 1863) Sproston, 1946, pilchardi van Beneden & Hesse, 1863) NEA Sprehn (1933) (as Octobothrium pilchardi (van Beneden & Hesse, 1863)) EM Papoutsoglou (1976)

Digenea Family Acanthocolpidae Lühe, 1906 Stephanostomum sp. (larva) M Nikolaeva & Parukhin (1969) Family Bucephalidae Bucephalid metacercaria (larva) WM Reichenback-Klinke (1957b)+ Family Faustulidae Poche, 1926 Bacciger bacciger (Rudolphi, 1819) Nicoll, 1914 M Nikolaeva & Parukhin (1969) WM Parukhin et al. (1971) NEA Shukhgalter (1998) NEA Shukhgalter & Rodjuk (2007) Pseudobacciger harengulae Yamaguti, 1939 NEA Gaevskaya (1996) NEA Dimitrov et al. (1999) Pronoprymna ventricosa (Rudolphi, 1819) Poche, WM Parukhin et al. (1971) (as Pentagramma 1926 symmetricum Chulkova, 1939)) WM Parukhin (1976) (as Pentagramma symmetricum) WM Present study* Family Hemiuridae Looss, 1899 Aphanurus stossichii (Monticelli, 1891) Looss, AD Stossich (1883) 1907 WM Monticelli (1887, 1891) (as Distoma ocreatum (Rudolphi, 1802) in 1887) NEA Rioja (1923) WM Reichenbach-Klinke (1958) WM Parukhin et al. (1971) EM Papoutsoglou (1976) WM Orecchia & Paggi (1978) AD Paradižnik (1987) NEA Shukhgalter (1998) AD Paradižnik & Radujković (2007) WM Present study* Aphanurus virgula Looss, 1907 WM Present study* Hemiurus appendiculatus (Rudolphi,1802)† AD Paradižnik & Radujković (2007) Hemiurus luehei Odhner, 1905 AD Looss (1907) (as ‘Hemiurus stossichi Monticelli of Lühe’ and H. rugosus Looss, 1907) NEA Nicoll (1914) (as H. ocreatus (Rudolphi, 1802); see Gibson & Bray, 1986) NEA Rioja (1923) (as H. appendiculatus (Rudolphi, 1802); see Gibson & Bray, 1986) AD Sey (1970a) (as H. rugosus) Table 6 Continued.

Parasite Area Reference NEA Martinez-Fernandez, in Cordero del Campillo et al. (1975) (as H. ocreatus; see Gibson & Bray, 1986) EM Papoutsoglou (1976) WM Orecchia & Paggi (1978) NEA Gibson & Bray (1986) NEA Shukhgalter (1998) WM Present study* Parahemiurus merus (Linton, 1910) Manter, 1940 M Nikolaeva (1966) (as Parahemiurus sardiniae Yamaguti, 1934; see Bray, 1990) M Nikolaeva & Parukhin (1969) (as Parahemiurus sardiniae Yamaguti, 1934; see Bray, 1990) WM Present study* Family Lecithasteridae Odhner, 1905 Lecithaster confusus Odhner, 1905 NEA Shukhgalter (1998) WM Present study* Lecithaster gibbosus (Rudolphi, 1802) Lühe, 1901 AD Sey (1970a) WM Parukhin et al. (1971) WM Orecchia & Paggi (1978) Family Lepocreadiidae Odhner, 1905 Holorchis pycnoporus Stossich, 1901 AD Paradižnik & Radujković (2007) Fam. et gen. incertae sedis Metacercaria ‘Rhodometopa’ (larva) WM Timon-David (1953) Trematode ‘?larvae’ NEA Pouchet & de Guerne (1887) Trematode spp. NEA Giard in Baudouin (1905)

Cestoda Family Bothriocephalidae Blanchard, 1849 Bothriocephalus scorpii (Müller, 1776) AD Sey (1970a) (probably larval) Family Grillotiidae Dollfus, 1969 Grillotia erinaceus (van Beneden, 1858) (larva) NEA Parukhin (1968) Family Onchobothriidae Braun, 1900 Calliobothrium sp. (larva) EM Papoutsoglou (1976) Family Phyllobothriidae Braun, 1900 Scolex pleuronectis Müller, 1788 (larva) WM Monticelli (1887) (as ‘Tetrabothrium’) WM Reichenbach-Klinke (1957a) WM Reichenbach-Klinke (1957b) WM Reichenbach-Klinke (1958) WM Parukhin et al. (1971) NEA Rego (1987) NEA Shukhgalter (1998) WM Present study*

Nematoda Family Anisakidae (Railliet & Henry, 1912) Anisakis simplex (Rudolphi, 1809) sensu lato WM Petter & Maillard (1988) (larva) EM Oğuz et al. (2000) WM Ruiz-Valero et al. (1992) NEA Shukhgalter (1998) M Santos et al. (2006) Anisakis pegreffii Campana-Rouget & Biocca, WM Larizza & Vovlas (1995) (as Anisakis simplex 1955 (larva) A)

41 Table 6 Continued.

Parasite Area Reference AD Larizza & Vovlas (1995) (as Anisakis simplex A) Anisakis sp. (larva) NEA Silva & Eiras (2003) WM Present study* Larval Anisakidae NEA Viu et al. (1996) "Ascaris engraulidis (Stossich, 1887) Stossich, AD Stossich (1887) (as Agamonema engraulidis) 1896" EM Barbagallo & Drago (1903) Contracaecum osculatum (Rudolphi, 1802) sensu M Santos et al. (2006) lato (larva) Contracaecum osculatum B (larva) NEA Kijewska et al. (2009) Contracaecum rudolphii Hartwich, 1964 (larva) RS Tantawy & Mahmoud (1999) Contracaecum sp. (larva) RS Tantawy & Mahmoud (1999) NEA Parukhin et al. (1971) “Contracaecum or Thynnascaris sp." (larva) NEA Carvalho-Varela & Cunha-Ferreira (1984) Hysterothylacium aduncum (Rudolphi, 1802) WM Reichenbach-Klinke (1957b) (as (larva) Contracaecum clavatum (Rud.)) WM Reichenbach-Klinke (1958) (as Contracaecum aduncum (Rud.)) EM Nikolaeva (1964) (as Contracaecum aduncum (Rud.)) M Nikolaeva & Naidenova (1964) (as Contracaecum aduncum (Rud.)) AD Sey (1970b) (as Contracaecum aduncum (Rud.)) WM Orecchia & Paggi (1978) (as Thynnascaris aduncum (Rud.)) AD Petter & Radujković (1989) AD Radujković & Raibaut (1989) AD Fioravanti et al. (1996) NEA Rello et al. (2008) WM Rello et al. (2008) M Santos et al. (2006) WM Present study* Hysterothylacium fabri (Rudolphi, 1819) Deardoff AD Sey (1970b) (as Contracaecum fabri (Rud.)) & Overstreet, 1981 (larva) EM Papoutsoglou (1976) Hysterothylacium sp. (larva) NEA Petter (1969) (as Thynnascaris sp.) NEA Rego (1987) (as Thynnascaris sp.) NEA Shukhgalter (1998) NEA Shukhgalter & Rodjuk (2007) Pseudoterranova decipiens (Krabbe, 1878) sensu M Santos et al. (2006) lato (larva) Fam. et gen. incertae sedis Nematode spp. NEA Giard in Baudouin (1905)

Acanthocephala Family Rhadinorhynchidae Travassos, 1923 Rhadinorhynchus lintoni Cable & Linderoth, 1963 WM Orecchia & Paggi (1978) Rhadinorhynchus sp. NEA Shukhgalter (1998) * See Appendix for prevalence and abundance data. † Probably a misidentification of Hemuiurs luehei. + Listed as an unidentified metacercaria in Reichenbach-Klinke (1957b), but as a bucephalid metacercaria in Reichenbach-Klinke (1958). 42

44 CHAPTER FIVE

THE PARASITE FAUNA OF BOOPS BOOPS

A total of 1,293 metazoan macroparasites belonging to 12 species was recovered from B. boops collected from the Gulf of Oran in Algeria. These included 5 adult and 3 larval trematodes, one monogenean, one larval nematode, one larval cestode and an isopode. This chapter presents infection parameters for all parasites in B. boops and detailed morphological redescriptions of four species.

Class Trematoda Rudolphi, 1808 Family Faustulidae Poche, 1926 Genus Bacciger Nicoll, 1914

Bacciger israelensis Fischthal, 1980

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 33.3-86.7%. Mean abundance: 1.50-3.73. Mean intensity: 2.89-3.96.

Description (Figures 5.1., 5.2.; Table 1) [Based on 15 whole-mounted adult specimens.] Body fusiform with slightly more narrowed posterior extremity resulting in a lemon-like outline in the ventral plane, 877-1,077 × 525- 648. Tegument thick, covered with minute spines. Parenhimal gland-cells present ventrally at the level of pharynx and cirrus-sac. Forebody 259-403 long (30.0-37.0% of body length). Oral sucker ventro-subterminal, subglobular, 104-126 × 115-141. Ventral sucker subspherical, smaller than oral sucker, 93-104 × 100-107. Sucker length ration 1:0.82-0.89, sucker width ratio 1:0.76-0.87. Prepharynx short or apparently absent. Pharynx muscular, elongate-oval, 56-81 × 61-74. Oesophagus short. Caeca lined with cells, end blindly at level of anterior margins of testes. Testes 2, large, oval, smooth, symmetrical, close posterior to ventral sucker, 104-155 × 111-148. Cirrus-sac large, 174-222 × 130-163, muscular, broadly oval, dorsal or anterodorsal

45 to ventral sucker, contains seminal vesicle, pars prostatica, ejaculatory duct and cirrus. Seminal vesicle saccular, bipartive; anterior portion smaller, 74 × 93, posterior portion 148 × 130. Prostatic cells large, duct of pars prostatica narrow. Cirrus small. Genital atrium deep, genital pore median. Ovary intertesticular, dorsal, larger than testes, 152-200 × 130-229, deeply tri-lobed, lobes 78-152 × 81-118. Laurer's canal and Mehlis' gland not seen, masked by uterine loops. Canalicular seminal receptacle observed in one specimen, elongate-oval, 59 × 37. Uterus occupies much of hindbody, with numerous loops posterior to gonads. Eggs yellow-brownish, operculate, numerous, 18-26 × 15-17. Vitellarium in two symmetrical groups (133-204 × 96- 192) of 5-8 masses of follicles each, at level of ventral sucker or just anterior; individual masses measuring 59-100 × 48-100; common vitelline duct prominent, ventral to ovary. Excretory vesicle prominent, V-shaped in appearance, with very short stem and long wide, reaching in forebody to pharynx level.

vitelline mass uterus

oral sucker

cirrus-sac

pharynx stem of excretory vesicle

Fig. 5.1. Bacciger israelensis ex Boops boops. Microphotograph of a specimen stained in toto. Scale-bar: 100 μm.

Remarks Existing data on the prevalence and abundance of this species indicate that it is a specific parasite of B. boops (see Dimitrov & Bray, 1994 for a discussion). Prior to its original description B. israelensis has been recorded in this host as Bacciger bacciger (Rudolphi, 1819) from both western and eastern Mediterranean (Sey, 1970; Parukhin et al., 1971);

46 Papoutsoglou, 1976; Parukhin, 1976; Orecchia & Paggi, 1978; Renaud et al., 1980; Cook et al., 1981; Naidenova & Mordvinova, 1997; Akmirza, 1998) and North East Atlantic (Cordero del Campillo et al., 1994) and as Bacciger harengulae Yamaguti, 1934 in the South East Atlantic (Parukhin, 1966, 1976). Records of B. israelensis in B. boops include those of Fischthal (1980, 1982), Saad-Fares (1985), Saad-Fares & Combes (1992a, 1992b) and Pérez- del-Olmo et al. (2004) from the eastern Mediterranean; of Lozano et al. (2001), Pérez-del- Olmo et al. (2004), Bartoli,et al. (2005) and Power et al. (2005) from the western Mediterranean; of Dimitrov & Bray (1994) from the Black Sea; and of Pérez-del-Olmo et al. (2004) and Power et al. (2005) from the North East Atlantic. Fischthal (1980) described B. israelensis based on material from B. boops and Sarpa salpa L. from Israel's coast of the Mediterranean. This species is one of the four considered valid within the genus Bacciger by Dimitrov & Bray (1994) who described B. israelensis based on material from B. boops from the Black Sea. The present material agrees morphologically with both the original description of B. israelensis and its redescription by Dimitrov & Bray (1994). However, the specimens examined from the Gulf of Oran have distinctly larger dimensions for body size and almost all organs, especially in comparison with the ranges provided by the latter authors (Table 5.1.). It is possible that these morphometric differences reflect variation among geographically distant populations. Unfortunately, although B. israelensis has been recorded in the western Mediterranean, no morphological data exist from this region. The present study therefore, expands the knowledge of the morphometric variation of B. israelensis.

Table 5.1. Comparative morphometric data for Bacciger israelensis.

Locality Gulf of Oran Eastern Mediterranean Black Sea (Algeria) (Israel) (Bulgaria) Source Present study Fischthal (1980) Dimitrov & Bray (1980) Body 877-1,077 × 525-648 571-879 × 395-550 486-652 × 295-425 Forebody 259-403 183-298 160-221 Oral sucker 104-126 × 115-141 85-109 × 85-121 75-95 × 82-100 Ventral sucker 93-104 × 100-107 70-92 × 73-98 72-91 × 73-98 Sucker length ratio 1:0.82-0.89 1:0.78-0.98 1:0.88-1.08 Sucker width ratio 1:0.76-0.87 1:0.80-0.87 1:0.81-1.03 Pharynx 56-81 × 61-74 48-75 × 53-75 48-56 × 48-62 Testes 104-155 × 111-148 90-140 × 75-145 28-119 × 21-82 Cirrus-sac 174-222 × 130-163 94-166 × 75-119 94-294 × 60-188 Anterior portion of 74 × 93 17-44 × 15-41 20-42 × 9-40 seminal vesicle Posterior portion of 148 × 130 32-77 × 24-63 35-64 × 16-49 seminal vesicle Ovary 152-200 × 130-229 120-174 × 97-174 82-122 × 70-95 Eggs 18-26 × 15-17 20-26 × 16-17 18-28 × 15-18

Fig. 5.2. Bacciger israelensis ex Boops boops. Line drawing, dorsal view with uterus in outline. Scale-bar: 300 μm.

48 Family Hemiuridae Looss, 1899 Subfamily Aphanurinae Skrjabin & Guschanskaja, 1954 Genus Aphanurus Looss, 1907

Aphanurus stossichii (Monticelli, 1891) Looss, 1907

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 26.7-66.7%. Mean abundance: 0.57-1.60. Mean intensity: 2.13-2.40. Deposition of material: BMNH 2011.7.7.5.

Description (Figures 5.3., 5.4.) [Based on 15 whole-mounted adult specimens.] Body plump, subcylindrical, 999-1,329 long, tapered anteriorly, widest at level of gonads or vitellarium, 234-388; width at ventral sucker 199-269. Ecsoma absent. Tegument thick, plicated both ventrally and dorsally along entire length of body. Forebody short, 169-239 (17.0-21.4% of body length). Pre-oral lobe distinct, 9-20. Oral sucker spherical, subterminal, 41-76 × 50-82. Ventral sucker muscular, spherical, much larger than oral sucker, 131-187 × 131-181. Prepharynx absent. Pharynx elongate-oval to subglobular, 47-58 × 35-58. Oesophagus apparently absent. Caeca wide, thick-walled, form small ‘Drüsenmagen’ just posterior to pharynx, reach fairly close to posterior extremity. Testes 2, transverse-oval, large, larger than or similar in size to ovary, oblique, contiguous or slightly separated, slightly anterior to mid-hindbody; right testis 44–91 × 58– 126, left testis 41-131 × 37-111. Seminal vesicle large, 105-237 × 64-155, elongate-oval, thick-walled (6-22), just anterior to or overlapping anterior testis dorsally, at 70-181 from posterior margin of ventral sucker (6.4-15.5% of body length). Pars prostatica tubular, long, with wide lumen and thick wall, enveloped by several layers of large gland-cells (main bulk between anterior testis and ventral sucker), prostatic cells field width 61-175. Sinus-sac tubular, 117-166 × 20-32, length 10.7-15.9% of body length and 17.0-21.4% of forebody length. Hermaphroditic duct tubular, straight, lined by small tubercles; its distal half forms eversible temporary sinus-organ. Genital pore median, at mid-level of or immediately posterior to oral sucker. Ovary post-testicular, fairly close to or contiguous with posterior testis, transversely oval, 44-102 × 105-165. Juel’s organ and Laurer’s canal not seen. Uterine seminal receptacle 49 present, dorsal to vitellarium. Uterine coils reach well posterior to vitellarium. Eggs operculate, thin-shelled, small in relation to size of body, 22-27 × 8-14. Vitellarium a single large, compact mass, distinctly larger than, posterior to and contiguous with ovary, in third quarter of hindbody (post-vitelline region 22.2-33.4% of body length), 70-146 × 105-210. Excretory pore terminal; details of excretory system not observed, but lateral arms unite dorsally to pharynx.

Remarks This species was first described from Sardina pilchardus under the name Apoblema stossichi Monticelli, 1891 (Monticelli, 1891). Looss (1907) erected Aphanurus to accommodate this species and described it on material from Lichia amia (L.), Boops boops (L.), Spicara maena (L.) and Trachurus mediterraneus (Steindachner). A. stossichii has recently been redescribed from B. boops from various localities in the North East Atlantic region (off Spain), the Mediterranean Sea (off Spain and Turkey) and the Black Sea (off Bulgaria) (Kostadinova et al., 2004). The present material agrees well morphologically with the data of Kostadinova et al. (2004). However, the specimens examined from the Gulf of Oran had larger values for the size of body and gonads and egg-length varied below the lower range recorded by Kostadinova et al. (2004) in the samples from B. boops in the North East Atlantic (22-27 vs 26-32 µm). These authors also documented some morphometric differences between populations of A. stossichii suggesting a possibility for existence of cryptic species. However, molecular evidence would be required to test this hypothesis. A. stossichii is one of the most frequently detected parasites of B. boops with a wide geographical distribution but especially characteristic for the Mediterranean. Thus there are nine records of this species from the western Mediterranean (López- Román & Guevara Pozo, 1974; Orecchia & Paggi, 1978; Renaud et al., 1980; Cook et al., 1981; Anato et al., 1991; Pérez-del Olmo et al., 2004; Kostadinova et al., 2004; Bartoli et al., 2005; Power et al., 2005) and 10 records from the eastern Mediterranean (Saad-Fares, 1985; Saad-Fares & Combes, 1992a,b; Sey, 1970; Papoutsoglou, 1976; Fischthal, 1980, 1982; Akmirza, 1998; Pérez-del Olmo et al., 2004; Kostadinova et al., 2004). Locality data were not provided in two additional Mediterranean records (Naidenova & Mordvinova, 1997; Parukhin, 1976) and two further records come from the Black Sea (Dimitrov, 1991; Kostadinova et al., 2004). Reports from the North East Atlantic, with the exception of those by Cordero del Campillo et al. (1975, 1994) have been published only recently (Pérez-del Olmo et al., 2004; Kostadinova et al., 2004; Power et al., 2005).

Fig. 5.3. Aphanurus stossichii ex Boops boops. Line drawing, ventral view with uterus in outline. Scale-bar: 300 μm.

arm of excretory vesicle

prostatic cells

seminal vesicle

Fig. 5.4. Aphanurus stossichii ex Boops boops. Microphotograph of a specimen stained in toto. Scale-bar: 100 μm.

Subfamily Hemiurinae Looss, 1899 Genus Hemiurus Rudolphi, 1809

Hemiurus communis Odhner, 1905

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 43.3-50.0%. Mean abundance: 0.63-1.03. Mean intensity: 1.43-2.07.

Description (Figure 5.5; Table 2) [Based on 15 whole-mounted adult specimens.] Body elongate-fusiform with maximum width at level of testes, 251-290. Soma 1,168-1,300 long, ecsoma 260-560 long. Tegument relatively thick, with annular plications ventrally and laterally, plications less distinct in

52 posterior third of soma and absent on ecsoma. Forebody very short, 225-240 (18.5-19.3% of soma length). Pre-oral lobe 18-20. Oral sucker spherical, ventrally subterminal, 70-76 × 73- 75. Ventral sucker muscular, subglobular, larger than oral sucker, 147-155 × 137-160. Sucker width ratio 1:1.8-1.9. Prepharynx absent. Pharynx subspherical, 47-55 × 47-57. Oesophagus very short. Caeca relatively narrow, thin-walled, form ‘Drüsenmagen’ just posterior to pharynx, end blindly close to posterior extremity of soma; may extend into ecsoma when extruded. Testes 2, elongate-oval to subglobular, smaller than or similar in size to ovary, oblique, contiguous or slightly separated, in anterior third of hindbody about halfway between ovary and ventral sucker; anterior testis 53-65 × 70-78, posterior testis 67-75 × 55-63. Seminal vesicle bipartite, 64-75 × 42-55, elongate-oval, thin-walled (6-22), between ventral sucker and anterior testis and close to the former. Pars prostatica tubular, long, enveloped by several layers of small gland-cells (main bulk anterior to ventral sucker), prostatic cells field 117-120 × 64-70. Sinus-sac tubular, with a thick wall, 91-112 × 26-35. Hermaphroditic duct short, tubular, straight. Genital pore median, at level of oral sucker. Ovary post-testicular, separated from posterior testis by uterine coils, transversely oval, 63-67 × 91-105. Juel’s organ, Laurer’s canal and uterine seminal receptacle not seen. Uterine coils reach well posterior to vitellarium, extending into proximal region of ecsoma when the latter extruded. Eggs operculate, thin-shelled, numerous, small, 22-24 × 9-12 (22.8 × 10.0). Vitellarium composed of two large, symmetrical, compact, slightly lobed masses (3-4 lobes), 93-120 × 93-105, posterior to and contiguous with ovary, in second third of hindbody. Excretory pore terminal on ecsoma, lateral arms unite dorsally to pharynx.

Table 5.2. Comparative morphometric data for Hemurus communis.

Locality Gulf of Oran (Algeria) Various hosts from various localities Source Present study Gibson & Bray (1986) Body 1168-1,300 × 251-290 450-4,000 × 105-850 Ecsoma 260-560 0-1,500 Forebody 225-240 110-600 Oral sucker 70-76 × 73-75 60-200 × 50-220 Ventral sucker 147-155 × 137-160 90-400 × 80-400 Sucker width ratio 1:1.8-1.9 1:1.57-2.30 Testes 55-75 × 55-78 20-220 × 20-250 Ovary 63-67 × 91-105 10-200 × 20-220 Vitelline mass 93-120 × 93-105 300 × 320 Eggs 22-24 × 9-12 22-29 × 9-15 (usually 24-28 × 10-12)

Fig. 5.5. Hemiurus communis ex Boops boops. Line drawing, ventral view with uterus in outline. Scale-bar: 300 μm.

54 Remarks The material studied keys down to H. communis using the key to species of Gibson & Bray (1986) and generally agrees well with the summed morphometric data provided by these authors. The upper limits for body size and all organs vary within the lower range for H. communis in the redescription of Gibson & Bray (1986) (Table 5.2). Previous records of H. communis in B. boops include six from the western Mediterranean (Renaud et al., 1980; Cook et al., 1981; Anato et al., 1991; Pérez-del Olmo et al., 2004; Bartoli et al., 2005; Power et al., 2005) and two each from the eastern Mediterranean (Akmirza, 1998; Pérez-del Olmo et al., 2004) and the North East Atlantic (Pérez-del Olmo et al., 2004; Power et al., 2005).

Subfamily Elytrophallinae Skrjabin & Guschanskaja, 1954 Genus Lecithocladium Lühe, 1901

Lecithocladium excisum (Rudolphi, 1819)

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 26.7-60.0%. Mean abundance: 0.33-1.40. Mean intensity: 1.25-2.33.

Remarks L. excisum has been recorded in B. boops from the wester Mediterranean by Orecchia & Paggi (1978), Pérez-del Olmo et al. (2004) and Power et al. (2005); the latter two authors also reported the occurrence of this species in fish populations from the North East Atlantic. There are two further records from the eastern Mediterranean (Saad-Fares, 1985; Fischthal, 1980) and two from non-specified localities in the Mediterranean (Parukhin, 1976; Naidenova & Mordvinova, 1997).

Family Lepocreadiidae Odhner 1905 Genus Lepocreadium Stossich, 1904

Lepocreadium album Stossich, 1890

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 13.3-26.7%.

55 Mean abundance: 0.13-0.50. Mean intensity: 1.00-1.88.

Description (Figures 5.6, 5.7. Table 5.3.) [Based on a single whole-mounted well-fixed adult specimen.] Body elongate-oval, rounded at both ends, 810 long, with maximum width 400 at level of mid-hindbody. Tegument thick, covered with fine spines. Sparce scattering of minute eye-spot pigment granules present in the region of prepharynx and pharynx. Pre-oral lobe absent. Oral sucker slightly transverse- elongate to subspherical, opens ventro-subterminally, 111 × 126. Ventral sucker round, faintly muscular, smaller than oral sucker, 118 × 89. Sucker-length ratio 1: 0.85–0.88; sucker-width ratio 1: 0.68–0.72. Forebody 185 (22.8% of body length). Prepharynx distinct, 56 long, with wide lumen. Pharynx large, elongate-oval, 104 × 107. Oesophagus very short. Caeca wide, end blindly posteriorly to posterior testis. Testes 2, in tandem, transversely oval, smooth, contiguous; anterior testis 115 × 159; posterior testis 130 × 163. External seminal vesicle saccular, elongate-oval, 141 × 74. Cirrus- sac thin-walled, elongate-oval, 144 × 78, dorsal to ventral sucker; contains small spherical internal seminal vesicle, 56 × 48, small prostatic cells and pars prostatica. Ejaculatory duct short. Genital pore close to ventral sucker. Ovary round, smooth, in mid-hindbody, contiguous with anterior testis, 81 × 67. Mehlis’ gland and Laurer’s canal not observed. Seminal receptacle saccular, close to external seminal vesicle, 85 × 93. Uterus short, with a few coils between gonads and ventral sucker, with few large eggs, 74-83 × 41-44. Metraterm not seen.Vitellarium in two lateral fields of follicles converging slightly at level of posterior testis, reach to fairly close to posterior extremity; anterior limit at level of oesophagus. Excretory pore dorso-subterminal, with faintly muscular sphincter; vesicle I-shaped, long.

Remarks Although L. album has been recorded in a range of sparid hosts (possibly the main hosts in the Mediterranean, see Akmirza, 1998, 2000; Bartoli, 1987; Saad-Fares, 1985; Saad-Fares & Maillard, 1990), this is only the fourth record of this species in B. boops (see Akmirza, 1998; Papoutsoglou, 1976; Pérez-del-Olmo et al., 2007). This is the first record of L. album in B. boops in the western Mediterranean. Morphologicaly the specimen examined agree with the descriptions of L. album but our data show that this species exhibits a higher variation for the

56 metrical features when parasitising B. boops (Table 5.3.). Thus, the specimen from the Gulf of Oran has a distinctly larger body (and therefore larger size for all organs) than the specimens examined by Pérez-del Olmo et al. (2007) from B. boops from the North East Atlantic. It has generally smaller dimensions, but appears closer to the specimen from another sparid, Diplodus annularis, examined in the Adriatic Sea by Radujković et al. (1989). These are likely populational differences since the egg-size vary in a narrow, overlapping range.

Fig. 5.6. Lepocreadium album ex Boops boops. Microphotograph of a specimen stained in toto. Scale-bar: 100 μm.

Fig. 5.7. Lepocreadium album ex Boops boops. Line drawing, ventral view with uterus in outline. Scale-bar: 300 μm.

58 Table 5.3. Comparative morphometric data for Lepocreadium album.

Locality Gulf of Oran (Algeria) Adriatic Sea North East Atlantic Host Boops boops Diplodus annularis Boops boops Source Present study Radujković et al. Pérez-del-Olmo et al. (1989) (2007) Body 810 × 400 1,940 × 890 421-483 × 144-192 Forebody 185 152-197 Oral sucker 111 × 126 200 × 190 64-75 × 78 Ventral sucker 118 × 89 150 × 160 56-64 × 53-80 Sucker length ratio 1:1.06 1:0.75 1:0.85-0.88 Sucker width ratio 1:0.70 1:0.84 1:0.68-0.72 Pharynx 104 × 107 190 × 160 67-82 × 59-64 Anterior testis 115 × 159 230-300 × 180-230 51-69 × 86-96 Posterior testis 130 × 163 as above 59-75 × 88-91 Cirrus-sac 144 × 78 220 × 90 61 × 45 Internal seminal vesicle 56 × 48 - 24 × 26 External seminal vesicle 141 × 74 - 38 × 26 Ovary 81 × 67 160 × 120 27-40 × 30-34 Seminal receptacle 85 × 93 - 24 × 34 Eggs 74-83 × 41-44 80-90 × 45-50 74 × 45

Digenean metacercariae (Figures 5.8, 5.9, 5.10)

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 16.7-43.3%. Mean abundance: 0.30-1.10. Mean intensity: 1.57-2.22.

Remarks Precise identification of all digenean metacercariae recovered in the samples of B. boops studied was not possible since this requires detailed morphological study of each individual. Therefore, for ecological analyses numbers of metacercariae per fish were pooled as 'digenean metacercariae'. However, at least three species use B. boops off Oran as second intermediate host: Tormopsolus sp. (Figs. 5.8, 5.9.); Stephanostomum sp. (Fig. 5.10 a); and Prosorhynchus crucibulum Rudolphi, 1819 (Fig. 5.10 b,c). B. boops acts as second intermediate host for at least seven digenean species in its distributional range (five of the family Acanthocolpidae Lühe, 1906 and one each of the families Bucephalidae Poche, 1907 and Strigeidae Railliet, 1919; see Pérez-del-Olmo et al., 2007 for a review). Recently, Pérez-del-Olmo et al. (2007) recorded metacercariae of the acanthocolpids Stephanostomum cesticillum (Molin, 1858) and Stephanostomum lophii

A B

Fig. 5.8. Tormopsolus sp. ex Boops boops. Microphotographs of specimens stained in toto showing suckers (A) and eyespot pygment concentrations lateral to pharynx (B). Scale-bars: 100 μm.

A B

Fig. 5.9. Tormopsolus sp. ex Boops boops. Microphotographs of A. Encysted metacercariae; B. Excysted metacercariae in vivo.

Fig. 5.10. Microphotographs of excysted metacercariae of Stephanostomum sp. (a) and Prosorhynchus crucibulum (b, c) ex Boops boops in vivo.

Quinteiro et al., 1993, and the bucephalid Prosorhynchus crucibulum Rudolphi, 1819 in B. boops populations from the North East Atlantic and brain metacercariae of the strigeid Cardiocephaloides longicollis (Rudolphi, 1819) in populations from the western Mediterranean. Other records from the Mediterranean include Stephanostomum bicoronatum (Stossich, 1883) (Anato et al., 1991), Stephanostomum euzeti Bartoli & Bray, 2004 (Pérez- del-Olmo et al., 2007) and Prosorhynchus crucibulum Rudolphi, 1819 (Anato et al., 1991). Stephanostomum impairispine (Linton, 1905) and unidentified metacercariae of the genus Prosorhynchus have aslo been reported in B. boops populations from the South East Atlantic by Parukhin (1966, 1976). The present study, therefore, presents the first record of metacercariae of the genus Tormopsolus and the second record of P. crucibulum in B. boops from the Mediterranean.

Class Monogenea Family Microcotylidae Taschenberg, 1879 Genus Microcotyle van Beneden & Hesse 1863

Microcotyle erythrini van Beneden & Hesse, 1863

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 13.3-26.7%. Mean abundance: 0.30-0.73. Mean intensity: 2.00-2.83.

Remarks M. erythrini is a frequent ectoparasite in B. boops in the western Mediterranean as evidenced by the largest number of records (12) (Parona & Perugia, 1890; López-Román & Guevara Pozo, 1973, 1974; Cordero del Campillo et al., 1975, 1994; Orecchia & Paggi, 1978; Renaud et al., 1980; Cook et al., 1981; Justine, 1985; Anato et al., 1991; Power et al., 2005; Pérez-del- Olmo et al., 2007) compared with North East Atlantic and Eastern Mediterranean (3 records each) (Cordero del Campillo et al., 1975, 1994; Power et al., 2005; Pérez-del-Olmo et al., 2007; and Papoutsoglou, 1976; Akmirza, 1998; Brinkmann, 1966, respectively).

61 Sub-class Eucestoda Fam. gen. incertae sedis

Scolex pleuronectis larva (Figure 5.11)

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 36.7-66.7%. Mean abundance: 1.57-10.45. Mean intensity:4.27-13.06.

Remarks Identification of tetraphyllidean larval cestodes is impossible because their scoleces remain undifferentiated until they infect the final host. Therefore, for the cestode larval stages in B. boops bearing an apical sucker and four acetabula (Fig. 5.11) we followed the common practice to use the ‘‘collective group name” Scolex pleuronectis that has been used in reference to larvae putatively identified as tetraphyllideans (Euzet, 1959; Jensen & Bullard, 2010).

Fig. 5.11. Scolex pleuronectis ex Boops boops. Microphotograph of a specimen stained in toto. Scale-bar: 200 μm.

S. pleuronectis is common in many teleost fishes and has been recorded eight times in B. boops in western Mediterranean (Joyeux & Baer, 1936; Renaud et al., 1980; Anato et al., 1991; Pérez-del-Olmo et al., 2007), eastern Mediterranean (Akmirza, 1998) and North East

62 Atlantic (Pérez-del-Olmo et al., 2007) ; two records from mediterranean have no locality specified (Parukhin, 1976; Naidenova & Mordvinova, 1997).

Phylum Nematoda Family Anisakidae (Railliet & Henry, 1912) Genus Hysterothylacium Ward & Magath, 1917

Hysterothylacium aduncum (Rudolphi, 1802) larva (Figure 5.12)

Dates of collection: 10.v.2007; 20.vii.2007; 8.x.2007; 10.ii.2008. Prevalence: 23.3-43.3%. Mean abundance: 0.53-0.83. Mean intensity: 1.92-2.86.

A B

C D

Fig. 5.12. Hysterothylacium aduncum ex Boops boops. Microphotographs of the anterior (A, B) and posterior (C, D) extremities.

63 Remarks H. aduncum has been recorded more frequently from B. boops populations studied in the western Mediterranean (6 records; Renaud et al., 1980); Cook et al., 1981; Petter, et al., 1984; Petter & Maillard, 1988a, 1988b; Pérez-del-Olmo et al., 2004) and Eastern Mediterranean (5 records; Sey, 1970; Papoutsoglou, 1976; Petter & Radujkovic, 1989; Radujkovic & Raibaut, 1989; Pérez-del-Olmo et al., 2004). This species has only recently reported from North East Atlantic (Pérez-del-Olmo et al., 2004). The larval specimens of the genus Hysterothylacium in the present study were assigned to H. aduncum following (Berland, 1991; Anderson, 2000). However, in previous collections we have identified also larvae of Hysterothylacium fabri (Rudolphi, 1819) (Dr. Montero, personal communication). It is possible therefore, that B. boops hosts both species in the area studied. To date, H. fabri has been only recorded in B. boops from the Eastern Mediterranean (Petter et al., 1984; Petter & Radujkovic, 1989; Radujkovic & Raibaut, 1989; Akmirza, 1998).

Order Isopoda Family Cymothoidae Dana, 1852 Genus Ceratothoa Dana, 1852

Ceratothoa oestroides (Risso, 1826) (Figure 5.13)

Dates of collection: 10.v.2007; 20.vii.2007; 10.ii.2008. Prevalence: 0-20.0%. Mean abundance: 0-0.37. Mean intensity: 1.67-2.00.

Remarks To date, nine published records for C. oestroides in B. boops exist, mostly from the western Mediterranean (Balcells, 1953; Vu Tan Tue, 1963; Trilles & Raibaut, 1971; López-Román & Guevara Pozo, 1976; Renaud et al., 1980; Anato et al., 1991) but also from populations from Eastern Mediterranean (Trilles et al., 1989) and North East Atlantic (Costa & Biscoito, 2003; Pérez-del-Olmo et al., 2007).

Fig. 5.13. Ceratothoa oestroides ex Boops boops. Scale in mm.

65 CHAPTER SIX

COMPOSITION AND STRUCTURE OF HELMINTH COMMUNITIES IN SARDINA

PILCHARDUS

6.1. COMMUNITY COMPOSITION

The description of helminth communities in S. pilchardus is based on a total of 163 S. pilchardus comprising six distinct samples (three collected in January, March and July 2006 and three collected in April, June and September 2007). Therefore, the entire sampling was representative for the examination of the seasonal variation (four seasons). Fish size was observed to vary within a narrow range (mean total length 14.3-16.1 cm; mean standard length 12.0-3.5 cm). However, there were significant differences in fish size among samples

(K-W test, H(5,163) = 37.29; p=0.0001). Subsequent pairwise multiple comparisons revealed that the sample collected in March 2006 had significantly higher values for total length (range for p=0.0001-0.001, see Fig. 6.1.).

17.5

17.0

16.5

16.0

15.5

15.0

Total Length (cm ) (cm Length Total 14.5

14.0

13.5 Mean Mean±SE 13.0 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

Fig. 6.1. Box-plots for total length of Sardina pilchardus in the six samples from the Gulf of Oran.

However, the correlation analysis carried out revealed that fish size was not significantly associated with parasite abundance (all p>0.05). Spearman rank order correlation 66 coefficients for all species had very low values ranging from -0.108 to 0.046. Thus, the size of the fish does not have a significant effect on parasite abundance that would affect comparisons of inracommunity parameters among samples (seasons). Table 6.1. summarizes the data on the species composition and prevalence and abundance of each species in the six parasite component communities studied. The overall prevalence of infection was lowest (70%) in the sample of January 2006 and the highest (100%) in the sample of September 2007. The remaining samples had very close values for overall prevalence (78.1-82.8%). A total of eight species (all helminths, transmitted to fish via food ingestion) was identified (Table 6.1). The predomiant group of parasites was trematodes (six species, five belonging to the superfamily Hemiuroidea). The other two parasites were the larval nematode H. aduncum and unidentified cestode larvae assigned to the collective group Scolex pleuronectis. The present study represents the first report of all eight species from off the Mediterranean coasts of Algeria. S. pilchardus is a new host record for Aphanurus virgula. The latter species, however, was found in a single sample (January 2006) and with a very low prevalence (5%); this species was considered to be an accidental parasite of S. pilchardus. Four species were identified as common (i.e. with prevalence > 30% in at least one sample). Of these, Pronoprymna ventricosa and Hemiurus luehei were common in all six component communities; the former species was most prevalent (prevalence > 50%) in five communities and the latter in one. Aphanurus stossichii was common in five communities and most prevalent in one (Table 6.1.). The larval cestode Scolex pleuronectis was common in only three communities and the remaining two species, Hysterothylacium aduncum and Lecithaster confusus, had prevalence lower than 30% in all communities where present. Parasite abundance generally followed the prevalence patterns but was very low (the maximum value of 2.63 worms was observed for the mean abundance of P. ventricosa in the sample of September 2007). A characteristic feature of the distribution patterns of the species in component communities in S. pilchardus from the Gulf of Oran, was the overall lack of significant differences in both prevalence and abundance between both seasons and samples. The p- values for all pairwise comparisons (Fisher's exact test) provided in Appendix 1 show that significant differences between samples were observed for a single species, P. ventricosa. This was due to the significantly higher prevalence of this species in the sample of September 2007 (83.3.% vs 35.0-55.2% in the remaining samples). However, Kruskal-Wallis tests carried out on parasite abundance did not reveal significant differences among samples for all

species (boxplots for the abundance of all species in the six component communities are given in Appendix 2).

Table 6.1. Prevalence (P%) and mean abundance (MA ± SD) of parasites of Sardina pilchardus in the samples from the Gulf of Oran.

Parasite species/Sample January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 P MA ± SD P MA ± SD P MA ± SD P MA ± SD P MA ± SD P MA ± SD Digenea Aphanurus virgula 5.0 0.05 ± 0.22 ------Aphanurus stossichii 25.0 0.60 ± 1.19 44.8 0.66 ± 0.97 46.9 1.06 ± 1.39 34.5 0.62 ± 1.05 34.5 0.55 ± 0.83 58.3 0.92 ± 0.93 Hemiurus luehei 45.0 0.70 ± 0.92 37.9 0.72 ± 1.10 50.0 1.31 ± 1.49 31.0 0.55 ± 0.95 31.0 0.69 ± 1.14 33.3 0.46 ± 0.72 Pronoprymna ventricosa 35.0 1.05 ± 2.09 55.2 1.41 ± 1.80 50.0 1.19 ± 1.49 55.2 1.93 ± 2.49 65.5 1.86 ± 2.13 83.3 2.63 ± 3.47 Parahemiurus merus 25.0 0.40 ± 0.75 34.5 0.66 ± 1.04 37.5 0.66 ± 1.04 24.1 0.38 ± 0.73 24.1 0.34 ± 0.67 45.8 0.92 ± 1.47 Lecithaser confusus 5.0 0.05 ± 0.22 - - 15.6 0.16 ± 0.37 ------Cestoda Scolex pleuronectis larva 30.0 1.35 ± 2.52 24.1 1.28 ± 2.99 40.6 1.88 ± 2.92 17.2 1.03 ± 2.60 27.6 1.38 ± 3.16 37.5 2.42 ± 3.66 Nematoda Hysterothylacium aduncum 25.0 0.45 ± 0.94 27.6 0.72 ± 1.39 18.8 0.41 ± 1.04 13.8 0.34 ± 0.97 17.2 0.24 ± 0.58 - - larva Total number of species 8 7 7 6 6 5 Most prevalent species - P. ventricosa P. ventricosa P. ventricosa P. ventricosa P. ventricosa H. luehei A. stossichii

6.2. COMMUNITY STRUCTURE

Infracommunity descriptors of helminth communities in S. pilchardus from the six samples and the results of the statistical comparisons are shown in Table 6.2. Although component communities comprised of 5 to 8 species and the number of species per infected fish ranged from 1 to 6 species, infracommunities were overall rather poor due to the generally low prevalence and abundance of the parasites and the presence of uninfected fish. The ranges and means for infracommunity richness (no. of species) and abundance (no. of individuals) provided in Figure 6.2. illustrate a general pattern of increase from the cold to the warm seasons in both years of study. Thus the maximum mean number of species per fish was observed in the samples of July 2006 and September 2007 (2.59 and 2.58, respectively) and the minimum was observed in the samples of April 2007 and January 2006 (1.76 and 1,95, respectively). The mean abundance of infracommunities followed the same pattern with maxima in September 2007 and July 2006 and minima in April 2007 and January 2006. However, there was a substantial overlap in the distributions of both species richness and abundance of infracommunities (Table 6.2.; Fig. 6.2.). Statistical comparisons revealed no significant differences between seasons and samples with respect to both infracommunity

richness (K-W test, H(3,163) = 4.21; p=0.240 and H(5,163) = 7.03; p=0.218, respectively) and

infracommunity abundance (K-W test, H(3,163) = 5.42; p=0.143 and H(5,163) = 6.97; p=0.223, respectively).

Fig. 6.2. Box-plots for the richness and abundance of infracommunites in Sardina pilchardus in the six samples from the Gulf of Oran.

Infracommunities in S. pilchardus exhibited low diversity (assessed by the Brillouin's index) due to the high levels of dominance, see Table 6.2). Thus, the values of the index of Berger-Parker ranged between 0.51 and 0.68 meaning that a single species represented on average 50-70% of the individuals in infracommunities. There were no significant differences between samples related to the diversity of the infracommunities (K-W test, H(5,133) = 9.20; p=0.100). However, samples differed significantly with respect to the levels of dominance (K-

W test, H(5,134) = 12.08; p=0.034). Pairwise comparisons revealed that this was due to the significantly higher dominance in the infracommunities sampled in June 2007 (Berger-Parker index 0.71) compared with infracommunities sampled in July 2006 (0.51) (Table 6.2).

Table 6.2. Infracommunity descriptors of helminth communities in Sardina pilchardus (mean ± standard deviation) and significance of differences (p-values from K-W test; R of ANOSIM and p for similarity) between the samples.

Parameter/Sample January March July April June September Sign. of 2006 2006 2006 2007 2007 2007 differences No. species/infected 1-6 1-6 1-6 1-6 1-5 1-4 - fish (range) Mean no. of species 1.95±1.76 2.24±1.68 2.59±1.93 1.76±1.46 2.00±1.54 2.58±1.10 p=0.218 Mean no. of 4.65±5.04 5.45±5.43 6.66±6.18 4.86±5.05 5.07±5.31 7.33±5.11 p=0.223 individuals Mean diversity 0.43±0.33 0.40±0.35 0.58±0.35 0.32±0.35 0.36±0.35 0.40±0.27 p=0.100 (Brillouin's index) Mean dominance 0.62±0.24 0.66±0.22 0.51±0.21 0.70±0.27 0.71±0.25 0.68±0.23 p=0.034 (Berger-Parker's index) Mean similarity (%) 34.32 32.61 38.68 32.51 36.61 41.59 R=0.006 (Bray-Curtis index) p=0.380

Levels of infracommunity similarity were very low (< 50%; range 32.5-41.6%; Table 6.2.). The results of the SIMPER test provided in Table 6.3. have identified the key species contributing to the similarity between the infracommunities in each sample. These were the three species found to be common and most prevalent in component communities: P. ventricosa, H. luehei and A. stossichii, plus S. pleuronectis in the sample of January 2006. P. ventricosa had high contribution to the similarity between infracommunities within most samples (except January 2006; range for percent contribution 22.9-63.7%) and A. stossichii and H. luehei were key species in three samples each. Generally, a combination of just two species showed more than 50% contribution to the observed similarities (Table 6.3). The multidimensional scaling (MDS) plot of infracommunities in the six samples indicated no significant differentiation with respect to community composition and structure between samples taken from different seasons (Fig. 6.3.). ANOSIM tests carried out on the similarity matrices confirmed the substantial homogenisation of infracommunities in S. pilchardus from the Gulf of Oran with no significant effect on community structure of either season (Global R=0.006; p=0.38) or sample (Global R=0.030; p=0.05) (see the results of the randomisation tests in Fig. 6.4.).

Table 6.3. Species that most contribute to the similarity (Bray-Curtis index) between infracommunities in the samples of Sardina pilchardus. Data on mean abundance [ln(x+1) transformed data], the percent contribution of each species to community similarity, and the cumulative percent similarity.

Sample Species Mean Contribution Cumulative abundance (%) (%) January 2006 H. luehei 0.63 38.8 38.8 S. pleuronectis 0.74 21.0 59.8

March 2006 P. venrticosa 0.78 36.4 36.4 A. stossichii 0.46 23.3 59.8

July 2006 H. luehei 0.80 27.5 27.5 P. venrticosa 0.74 22.9 50.4

April 2007 P. venrticosa 0.95 60.3 60.3 A. stossichii 0.42 16.8 77.1

June 2007 P. venrticosa 0.97 63.7 63.7 H. luehei 0.43 14.1 77.7

September 2007 P. venrticosa 1.02 52.1 52.1 A. stossichii 0.53 17.9 70.0

Fig. 6.3. Non-metric multidimensional scaling ordination of infracommunities in Sardina pilchardus in the six samples from the Gulf of Oran. Seasons of sampling indicated by different colours. Abbreviations: W, winter; S, spring; SU, summer; A, autumn.

Fig. 6.4. Simulated distribution (blue bars, 999 randomisations) of the test statistic R under the hypothesis of no seasonal differences between infracommunities. The observed value of R = 0.006 is indicated by a line.

6.3. DISCUSSION

The clupeid Sardina pilchardus is an important component of the marine ecosystems in the Mediterranean and Nort East Atlantic. As primary feeder in the marine food web, S. pilchardus is the main prey for dolphins and many fish species. Furthermore, this fish is an important resourse for the human populations along the coasts of the Mediterranean and North East Atlantic and, as a consequence, one of the most exploited, the stocks being overexploited in many areas in the Mediterranean (see Chapter 1). The need to expand the knowledge on parasites in this host, therefore reflect its trophic level and importance in the food webs but also the possible harazds for human health associated with infections with Anisakis spp. Furthermore, parasite communities may also reflect the degree of exploitation of the fish host (see Chapter 7). However, existing data on parasites of S. pilchardus are fragmentary and comptise (with a few exceptions) only isolated records with no confirmation for parasite identification. This first study on the helminth fauna of S. pilchardus along the Algerian coasts of the Mediterranean is also the first to examine the structure of its parasite communities.

We have expected, based on studies on parasite communities in small pelagic primary feeders (e.g. Tavares et al., 2005) to observe low species richness and abundance of infracommunities in S. pilchardus and the predominance of larval nematodes. However, contrary to these expectations the following patterns were most characteristic: (i) the lack of correlation between fish size and parasite abindance; (ii) dominance of trematodes; (iii) very low infection parameters. A total of nine species (all helminths, transmitted to fish via food ingestion) was identified. Although larval Anisakis sp. were recovered in some fish, the prevalence and abundance were very low and they were not included in the quantitative comparisons. Overall, we have found no potential health hazard from the populations of S. pilchardus in the Gulf of Oran. The most prevalent in all population samples studied were adult trematodes with just one species, Pronoprymna ventricosa, dominant in all samples except January. Parasite infracommunities were characterised by low richness, abundance, diversity, similarity and high dominance. There were no significant effects on parasite prevalence and abundance and community structure of either season or sample. Parasite communities in S. pilchardus in the Gulf of Oran, therefore, were characterised by substantial homogeneity. This is partially due to planctonic feeding of the host but may also be indicative of overfishing. Unfortunately, there are no data from other regions from the Mediterranean or North East Atlantic that would allow a comparative study.

CHAPTER SEVEN

Effects of fishing on parasitism in a sparid fish: Contrasts between two areas of the Western Mediterranean

Douniazed Marzouga, Zitouni Boutibaa, Aneta Kostadinovab & Ana Pérez-del Olmoc,*

aLaboratoire Réseau de Surveillance Environnementale, Département de Biologie, Université d'Oran, 31000 Oran, Algeria bInstitute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 České Budějovice, Czech Republic

cXRAq (Generalitat de Catalunya), Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain

Submitted Manuscript (Parasitology International)

74 Abstract This study addressed the impacts of fishing on the rates of parasitism using the sparid Boops boops as model fish species. Using a large suite of parasite species in B. boops, with different life histories that utilise different transmission pathways we compared parasite prevalence, abundance and community structure at two Mediterranean localities, Santa Pola Bay and the Gulf of Oran, that exhibit a contrasting pattern of fishing of B. boops. A total of 360 fish was studied comprising nine distinct samples collected during the warm and the cold weather months. A total of 29 parasite species was identified, with eight species in common for the two localities. Parasite component communities at Santa Pola were more species rich and abundant than those at the Gulf of Oran and exhibited a different community structure. Of the eight common taxa used in the quantitative comparisons, five exhibited significant difference for prevalence between the two localities, four having substantially higher prevalence at Santa Pola and only being more prevalent at the Gulf of Oran. Two specialist trematodes and the sparid generalist monogenean exhibited consistently higher prevalence and abundance at Santa Pola Bay than at the Gulf of Oran, the former two also identified as key species for assigning individual fish to their locality of origin. The consistent differences in the richness, abundance and structure of parasite infracommunities in B. boops from Santa Pola Bay and the Gulf of Oran may reflect the contrasting patterns of exploitation of the populations of this fish host at the two localities.

1. Introduction

One of the most pervasive human impacts in the oceans is fish removal that, for hundreds of years has affected marine ecosystems on a global scale (Jackson et al., 2001; see Wood et al., 2010 for a review). Classic epidemiological theory predicts that a minimum host density (threshold density for parasite transmission, see Wood et al., 2010) is required to ensure pathogen persistence within a host population i.e. satisfying the condition that transmission to new hosts is greater than the loss of infected hosts resulting from mortality or recovery from infection (McCallum et al., 2005; Wood et al., 2010). Models by Dobson & May (1987) suggest that fishing can result in reduction of population densities below the threshold values for parasite transmission thus leading to removal or 'fishing out' of the parasite. Recently, Wood et al. (2010) reviewed the theoretical predictions and empirical studies addressing the questions of the effects of fishing host populations on the abundance of their parasites and suggested that, in spite of the complexity and variability of its effects, fishing will generally tend to reduce the abundance and diversity of parasites as predicted by Dobson & May (1987). However, few empirical studies have documented shifts in fish macroparasite

75 populations associated with different levels of fishing pressure (Amundsen & Kristoffersen, 1990; Sasal et al., 1996; Sasal et al., 2004; Loot et al., 2005; Lafferty et al., 2008). This study addresses the impacts of fishing on the rates of parasitism at the population and community level, using a model fish species, Boops boops (L.) (Teleostei: Sparidae). B. boops is one of the most abundant species in both the Mediterranean and North east Atlantic (e.g. Valle et al., 2003; Boyra et al., 2004) that acts as final and intermediate host for a large number of macroparasites (Pérez-del-Olmo et al., 2007). Using a large suite of parasite species in B. boops, with different life histories that utilise different transmission pathways we compared parasite prevalence, abundance and community structure at two Mediterranean localities, Santa Pola Bay and the Gulf of Oran, that exhibit a contrasting pattern of fishing of B. boops, characteristic for the exploitation of the populations of this species along the European and African coasts of the Mediterranean, respectively.

2. Materials and Methods

2.1. Study localities

We selected two localities in the Balearic Sea (division 37.1.1.; FAO major fishing area 37 Mediterranean and Black Sea) as representative for the impact of the contrasting fishing pressure exerted on the populations of the model fish along the European and African coasts of the Western Mediterranean: Santa Pola Bay (Spain; 38°09′N, 0°31′W) and the Gulf of Oran (Algeria; 35°45′N, 0°39′W). The two localities are separated by c. 140 nautical miles. Main target species of the multispecies artisanal fishery in the Bay of Santa Pola represent crustaceans and fish with high market value such as Epinephelus marginatus, Sparus aurata, and Dicentrarchus labrax followed by Mullus surmuletus and Dentex dentex (Forcada et al., 2010). Due to its low market value Boops boops is not a subject to targeted fishery along the Spanish Mediterranean and at Santa Pola Bay in particular and represents a small fraction of by-catches. On the other hand, market demand for B. boops is strong in southern Mediterranean countries such as Egypt, Tunisia, Algeria and Morocco. This species constitutes an important resource subjected to targeted fishing along the Algerian coasts and at the Gulf of Oran. Thus a comparison of the landings registered in 2007-2010 at the ports of Oran and Santa Pola indicates a consistent extraordinarily high fishing pressure in the fishing grounds off Oran with catches 22-39 times as large as those at Santa Pola (787-1,157 vs 12-39 tonnes,

76 respectively; Fig. 1). This pattern is consistent with the one for the national landings of B. boops over the last decade (Fig. 1; inset) with values for Algeria on average 13 times as large as those for Spain. These data justify our classification of B. boops populations at the two study localities as representative of two contrasting patterns of fishing pressure typical for the Mediterranean, i.e. targeted fishing and non-targeted fishing (corresponding to strong and weak exploitation of the fish populations at the Gulf of Oran and Santa Pola Bay, respectively). Although we could not find assessments for Spanish or Algerian waters, B. boops stock in the neighbouring southern Alboran Sea (off Morocco where similar fishing pressure is exerted) is considered to be overexploited (FAO, 2011); this supports our selection.

2.2. Model fish

The bogue, Boops boops (Teleostei: Sparidae), is a demersal to semipelagic, non-migratory fish which is common in the North East Atlantic and one of the most abundant species in the Mediterranean Sea. It is gregarious, found on the shelf or coastal pelagic on various bottoms at a depth range 0-350 m. B. boops is omnivorous with an intermediate trophic level (2.53 - 3.30; Stergiou & Karpouzi, 2002), feeding mainly on benthic copepods and plants but is also planktonophagous (copepods) (Jukic, 1972; Froese & Pauly, 2011). B. boops attains its maximum trophic level early in the life span and no significant alteration of the trophic level with size/age have been reported (Stergiou & Karpouzi, 2002; Karpouzi & Stergiou, 2003). The intermediate trophic level and diverse diet of B. boops indicate that parasite communities in this host are likely to reflect both local food-web structure and predatory-prey interactions. Furthermore, the site fidelity of the model host would allow detection of relationships between fishing and parasites richness and abundance at local spatial scales. B. boops hosts a large number of metazoan parasites (67 species) among which Pérez- del-Olmo et al. (2007) have identified a group of eight key species in this host based on their distributional range in published records. This group includes both parasites for which B. boops acts as the main definitive host (Bacciger israelensis and Aphanurus stossichii) and species parasitizing a number of sparids (Microcotyle erythrini) and a wide range of fish hosts (Hemiurus communis, Lecithocladium excisum, Hysterothylacium aduncum, Anisakis simplex, and Ceratothoa oestroides). These species were also found to infect fish early in the ontogeny (Pérez-del-Olmo et al., 2008). Finally, due to the strong abundance-distribution relationships of the parasites of B. boops (Pérez-del-Olmo et al., 2009), the widespread species play a major role in shaping communities in this host.

2.3. Fish and parasite samples

A total of 360 fish was studied comprising nine distinct samples. Five samples (140 fish) collected in Santa Pola Bay and four samples (120 fish) collected in the Gulf of Oran provided comparative data on the variations in parasite populations and community structure during the warm and the cold weather months in the two areas (May-July and October- February, respectively). We examined only adult fish (age range 2-6 years) in order to avoid possible bias in parasite abundance due to the bathymetric juvenile-mature segregation (Dempster et al., 2002; Sánchez et al., 2004; see Pérez-del-Olmo et al., 2008). Sampling effort was standardised (c. 30 fish per distinct sample). Fish transferred on ice to laboratory were measured, labelled individually and examined for both ecto- and endoparasites according to a standardized protocol. Parasites were fixed and stored in 70% alcohol. Monogeneans, digeneans, cestodes and acanthocephalans were stained with iron acetocarmine and examined as permanent mounts in Canada balsam. Nematode larvae were identified on temporary mounts in saline solution or glycerine. Isopods were examined in saline solution. All macroparasites were identified and counted.

2.3. Statistical analyses

Ecological terms are used according to Bush et al. (1997). Species with prevalence higher than 30% in any of the samples will further be referred to as common. These species were considered for quantitative comparisons of parasite prevalence, abundance and community structure. All larval digeneans (five species) were identified and counted in each fish individual in the samples from Santa Pola Bay. However, although three species of larval digeneans were identified (Prosorhynchus crucibulum, Tormopsolus sp. and Stephanostomum sp.) in the samples from the Gulf of Oran and the total counts of the metacercariae from each fish individual were obtained, it was not possible to reach their precise identification. Therefore, to ensure consistency between the two localities, larval trematode counts were grouped under the collective name 'digenan metacercariae'. We assessed differences in prevalence (percent of fish infected with a given parasite species) among localities for the common species (i.e. seven identified species and the collective group 'digenean metacercariae') with Chi-square tests (Quantitative Parasitology (QP3.0), Rózsa et al., 2000). To examine the effects of locality and season (2 levels, warm and cold seasons) and their interaction on parasite abundance (number of parasites per fish individual; data ln (x+1)

78 transformed), we used a generalised linear model (GLM) with fish standard length as a covariate. Since significant interaction between the factors season and locality were detected in theses analyses, we examined the effect of locality on abundance in separate GLMs (cold and warm weather seasons) with fish standard length as a covariate and assessed parasite prevalence separately for each season. Analyses at the community level were carried out with PERMANOVA+ for PRIMER v6 software (Anderson et al., 2008). To assess the effects of locality and season (and their interaction) on the composition and structure of parasite communities of the common species we used permutational multivariate analysis of variance (PERMANOVA, Anderson, 2001). A two-way crossed experimental design was constructed with each factor having two levels using mean abundance of the species in component communities (all parasites in a distinct fish population sample; data square-root transformed). Permutation P-values were obtained under unrestricted permutation of raw data (9999 permutations). To asses the importance of fishing pressure on the variations in parasite infracommunity (all parasites in a host individual) composition and structure we used Random Forests (RF) for discrimination of individual with respect to the locality of sampling using abundance distributions of the common species as predictor variables. The RF classification model (100 trees; training set n=179; test set n=81) was developed with Statistica 8.0 (StatSoft, Inc., Tulsa, OK, USA).

3. Results

Taking into account both localities, a total of 29 parasite species was identified, with eight species in common. Fish examined at Santa Pola Bay were infected with 28 species: three monogeneans, 17 digeneans (12 adult and five larval forms), five nematodes (two larval), one copepode, one isopod, and a larval cestode). Fifteen species were registered at Santa Pola only, seven of them found only during the warm seasons and two during the cold seasons only (Table 1). Examination of the fish samples from the Gulf of Oran revealed nine identified species (one monogenean, five trematodes, one larval nematode, one larval cestode, and one isopod). The parasite species list from the Gulf of Oran comprised a subset of the species list of the parasites found off Santa Pola, with the exception of the adult digenean Lepocreadium album found only in the fish from the Gulf of Oran. Parasite component communities at Santa Pola were richer than those at the Gulf of Oran in both warm and cold seasons (22 vs 10 spp. and 17 vs 10 spp., respectively). This almost twice as high richness was assessed considering digenean metacercariae as a single

79 taxon. The overall rates of infection were lower at the Gulf of Oran (88.3-91.7%) while all fish sampled at Santa Pola Bay were infected. Of the eight common taxa used in the quantitative comparisons, five exhibited significant difference for prevalence between the two localities. Four species (the digeneans Aphanurus stossichii and Bacciger israelensis, the monogenean Microcotyle erythrini and the larval nematode Hysterothilacium aduncum) had substantially higher prevalence at Santa Pola (χ2 =55.69, P=0.0001; χ2 =28.83, P=0.0001; χ2 =22.46, P=0.0001; χ2 =10.70, P=0.001, respectively, see Fig. 2). On the other hand, only one species, the larval cestode Scolex pleuronectis, was more prevalent at the Gulf of Oran (χ2 =19.64, P=0.0001). Overall prevalence did not differ significantly between locations for the remaining three species (the digeneans Hemiurus communis and Lecithocladium excisum and the collective group 'digenean metacercariae' (Fig. 2). Results of the first series of GLM models on parasite abundance showed that locality significantly explained the abundance of three species (A. stossichii, B. israelensis and S. pleuronectis) and infracommunity richness and abundance. The variation found in the latter two paramenters and the abundance of H. communis and M. erythrini were also significantly affected by the season of sampling (Table 2). Fish size had a significant effect in GLMs on abundance of two species (H. communis and M. erythrini; Table 2). Furthermore, there was a significant locality by season interaction for B. israelensis, H. communis, L. excisum, S. pleuronectis, M. erythrini and infacommunity abundance. This prompted us to run GLMs for the samples from the warm and the cold seasons separately. GLM models constructed for parasite abundance within season using fish standard length as a covariate showed that locality significantly explained the variation in abundance of six species in fish sampled during the warm seasons (significance levels for Wald χ2 given in Table 1). Four species (A. stossichii, B. israelensis, M. erythrini and H. communis) had substantially higher abundance in fish from Santa Pola Bay and two (L. excisum and S. pleuronectis) were significantly more abundant in fish from the Gulf of Oran. However, GLMs for the cold seasons revealed a significant effect of locality on abundance of just two species (A. stossichii and B. israelensis). Parasite infracommunities in fish sampled at Santa Pola Bay had higher species richness and abundance than those sampled at the Gulf of Oran in both warm and cold seasons (Table 2); no effect of fish size was detected in all models. Component parasite communities in the nine distinct fish population samples exhibited substantial differentiation with respect to locality (Fig. 3; PERMANOVA Pseudo-

F(1,5)=16.833, P(perm)=0.0017) whereas the effect of factor season was not significant (Pseudo-

F(1,5)=2.188, P(perm)=0.137). This is supported by the greatest component of the overall variation due to the effect of the factor locality (628.76 vs 47.18 for factor season and 173.28

80 for residual variation). We applied a RF classification model on the common species in the total dataset to assess the degree to which this community differentiation translates into infracommunities. Although there was a higher variation within the samples from the Gulf of Oran (test-set error rate 13.6% vs 9.1% for Santa Pola) individual fish were classified to their localities of sampling with an overall high accuracy (86.4%; test-set, see Fig. 4). Two variables, the abundance of A. stossichii and B. israelensis had notably high importance in the development of the RF model that successfully discriminated fish individuals sampled from Santa Pola Bay and the Gulf of Oran.

4. Discussion

Theory predicts that fishing leading to substantial reductions of fish populations would also lead to elimination or 'fishing out' of the populations of their parasites (Dobson & May, 1987; Lafferty & Holt, 2003). In spite the importance and ubiquitous nature of overfishing and the roles of parasites in structuring host populations and communities, 'fishing out' parasites has received attention only recently (Ward & Lafferty, 2004; McCallum et al., 2005; Wood et al., 2010). However, empirical support for this prediction originating from studies on fish populations in the marine environment is critically lacking. Thus, the few studies published to date concern differences in prevalence and abundance of single parasite species in marine reserves (Sasal et al., 1996; Sasal et al., 2004; Loot et al., 2005). Recently, Lafferty et al. (2008) addressed the impacts of fishing on levels of parasitism in five fish species off two coral atolls of the Central Pacific. They found higher overall parasite richness, prevalence and abundance in the fish examined at Palmyra atoll which they assumed to represent a non-fished condition due to the lack of permanent human population compared to heavily fished Kiritimati Island. Detailed abundance comparisons carried out by these authors also revealed that only 6 out of 25 host-parasite combination contrasts between fished and non-fished conditions were significant. Unfortunately, this study was based on unidentified parasites coarsely grouped into higher-level operational taxonomic units thus preventing analysis based on the knowledge of parasite pathways in the two atoll ecosystems (Lafferty et al., 2008). To the best of our knowledge, our study is the first assessment of parasite populations and communities in a fish host from areas with contrasting fishing pressure, that is based on a rich, taxonomically consistent dataset of parasites identified to the species level. Our comparative study at the two localities of the western Mediterranean that differ in the exploitation of the stocks of the sparid B. boops, i.e. targeted vs non-targeted fishing, revealed contrasting patterns of levels of parasitism and parasite community structure. Macroparasites

81 in B. boops at Santa Pola Bay exhibited a remarkably higher diversity, more than 3 times higher than at the Gulf of Oran if all identified species are considered (more than 2.5 times excluding digenean larval stages). In its distributional range and at Santa Pola in particular, B. boops acts as a host of a large number of generalist parasites transmitted from its fish and mammal predators (larval forms) but also from other sympatric host species (adult forms) (for details see Pérez-del-Olmo et al., 2008, 2009). The high orverall richness and the large number of parasites found only at Santa Pola, therefore, indicates a higher complexity of the food web at Santa Pola, and perhaps higher densities of sympatric fish species resulting in increased opportunities for completion of parasite transmission pathways (e.g. Lafferty et al., 2006; Marcogliese et al., 2006). Perhaps the most important strength of the comparative aspect of our study is the finding that a number of common species consistently recruited to the populations of B. boops at both localities. This indicates that environments at Santa Pola Bay and the Gulf of Oran provide conditions for both completion of the life-cycles and sustaining the populations of these species locally. A further advantage of the dataset used in the present comparisons was the consistency of parasite identification. This allowed us to link differences in levels of parasitism with parasite specificity and transmission pathways at the level of individual species. Among the common species in the fish populations studied in Santa Pola Bay and the Gulf of Oran were species of the three general groups: specialised parasites utilising B. boops species as the main definitive host (B. israelensis and A. stossichii); sparid generalist (M. erythrini) and generalist species (Hemiurus communis, Lecithocladium excisum, Hysterothylacium aduncum, Scolex pleuronectis and digenean metacercariae). Notably, the two specialist trematodes and the sparid generalist monogenean exhibited consistently higher prevalence and abundance at Santa Pola Bay than at the Gulf of Oran; the former were also identified as key species for assigning individual fish to their locality of origin. The patterns depicted for the generalist species were more variable and appeared to reflect seasonal differences in local host communities and the roles of B. boops as intermediate host. Thus, although there was no significant effect of locality on the prevalence and abundance of the two generalist species that also mature in B. boops, L. excisum and H. communis, we detected a significant locality by season interaction in defining the variations in abundance of both species with significant differences between the samples collected during the warm seasons. The metacercariae of both species infect harpacticoid copepods Acartia spp. but also use additional transmission pathways using ctenophores and chaetognaths (H. communis) as parartenic hosts (Rebecq, 1965; Noble, 1972; Gibson and Bray, 1986; Køie, 1991, 1992, 1995). The main hosts of L. excisum are Scomber scombrus and S. japonicus but

82 it can occasionally occur in the carangids Trachurus trachurus and T. mediterraneus and other fishes that occupy similar ecological niches and feed on ctenophores (Gibson & Bray, 1986). On the other hand, H. communis is a common parasite in a wide range of marine teleosts (Gibson & Bray, 1986). The opposite patterns of abundance observed L. excisum being more prevalent and abundant at the Gulf of Oran and H. communis at Santa Pola Bay, respectively, may thus reflect differences in local plankton or teleost composition and/or abundance during the warm seasons. Infection parameters of the generalist larval parasites in B. boops appeared to depict a similar and rather modest contribution of the populations of this host to the transmission rates of the larval digeneans and the larval nematode H. aduncum at both localities (albeit the latter with a higher prevalence at Santa Pola). However, the prevalence and abundance of S. pleuronectis, a collective group for larval tetraphyllidean cestodes presumably parasitic in elasmobranchs, were distinctly higher at the Gulf of Oran than at Santa Pola Bay. The diversity of demersal elasmobranchs in Algerian waters is among the highest in the Mediterranean basin, much higher than in the waters off the Iberian Peninsula and approaching only that of Balearic Islands (Massutí & Moranta, 2003; Ordines et al., 2011). This has been attributed partially to the underdevelopment of the deep water trawl fishery in Algeria (Mouffok et al., 2008). The consistently higher infection parameters in B. boops support the idea of a higher diversity and abundance and lower fishing pressure exerted on elasmobranchs at the Gulf of Oran. Similarly, Lafferty et al. (2008) observed lower abundances of larval shark tapeworms in fishes at the heavily fished Kiritimati Island. Overall, our results provide support for the prediction for differential effects, associated with the degree of host specificity, of the reduction of host population density on parasite abundance (Lafferty & Holt, 2003: Wood et al., 2010). Environmental and fishing effects are notoriously difficult to disentangle (Rogers et al., 1999; Wood et al., 2010 and references therein). In temperate waters seasonal changes in species richness, abundance and structure of benthic macroinvertebrate communities (e.g. Arias & Drake, 1994), and mollusc assemblages in particular (Rueda & Salas, 2003 and references therein), provide additional levels of variation for parasite communities in marine fishes. Thus, repetitive seasonal trends with higher richness and abundance in molluscan assemblages in the warm (spring and summer) vs cold (autumn and winter) seasons (e.g. Rueda & Salas, 2003) have been reported along both Mediterranean and Atlantic coasts of Spain. These changes inevitably affect transmission rates of the most diverse parasite group in B. boops, the digeneans that require a mollusc host to complete their life cycles (Pérez-del- Olmo et al., 2009). Our study revealed the confounding effect of seasonal patterns of

83 prevalence and abundance in comparisons between localities for the generalist parasites of B. boops. Nevertheless, the two species that use this fish as the main host, exhibited consistent patterns of difference between localities. This has resulted in consistent differences in the richness, abundance and structure of parasite infracommunities in B. boops from Santa Pola Bay and the Gulf of Oran. We conclude, that these differences reflect the contrasting patterns of exploitation of the populations of this fish host at the two localities.

References

Amundsen, P.A. & Kristoffersen, R. (1990) Infection of whitefish Coregonus lavaretus L. sensu Lato by Triaenophorus crassus Forel Cestoda Pseudophyllidea: a case study in parasite control. Canadian Journal of Zoology, 68, 1187-1192. Anderson, M.J. (2001) Permutation tests for univariate or multivariate analysis of variance and regression. Canadian Journal of Fisheries and Aquatic Science, 58, 626-639. Anderson, M.J., Gorley, R.N. & Clarke, K.R. (2008) PERMANOVA+ for PRIMER: Guide to Software and statistical methods. PRIMER-E: Plymouth, UK. Arias, A.M. & Drake, P. (1994) Structure and production of the benthic macroinvertebrate community in a shallow lagoon in the Bay of Cádiz. Marine Ecology Progress Series, 115, 151-167. Boyra, A., Sanchez-Jerez, P., Tuya, F., Espino, F. & Haroun, R. (2004) Attraction of wild coastal fishes to an Atlantic subtropical cage fish farm, Gran Canaria, Canary Islands. Environmental Biology of Fishes, 70, 393-401. Bush, A.O., Lafferty, K.D., Lotz, J.M. & Shostak, A.W. (1997) Parasitology meets ecology in its own terms: Margolis et al. revisited. Journal of Parasitology, 83, 575-583. Dempster, T., Sanchez-Jerez, P., Bayle-Sempere, J. T., Giménez-Casalduero, F. & Valle, C. (2002) Attraction of wild fish to sea-cage fish in the south-western Mediterranean Sea: spatial and short-term temporal variability. Marine Ecology Progress Series, 242, 237- 252. Dobson, A. & May, R. (1987) The effects of parasites on fish populations - theoretical aspects. International Journal for Parasitology, 17, 363-370.

84 FAO (2011) General Fisheries Commission for the Mediterranean. Scientific Advisory Committee, Session 13, Inf. 8. Draft report of the 12th session of the SAC sub- committee on stock assessment (SCSA), Saint George’s Bay Malta, 28 November-3 December 2010. Forcada, A., Valle, C., Sánchez-Lizaso, J.L., Bayle-Sempere, J.T. & Corsi, F. (2010) Structure and spatio-temporal dynamics of artisanal fisheries around a Mediterranean marine protected area. ICES Journal of Marine Science, 67, 191-203. Froese, R. and Pauly, D. (Eds) (2011). FishBase. World Wide Web electronic publication. www.fishbase.org, version (04/2010). Gibson D.I. & Bray R.A. (1986) The Hemuiridae (Digenea) of fishes from the north-east Atlantic. Bulletin ofthe British Museum (Natural History), Zoology Series, 51, 1-125. Jackson, J.B., Kirby, M.X., Berger, W.H., Bjorndal, K.A. & Botsford, L.W. (2001). Historical overfishing and the recent collapse of coastal ecosystems. Science, 293, 629–637. Jukic, S. (1972) Nutrition of the hake (Merluccius merluccius), bogue (Boops boops), striped mullet (Mullus barbatus) and pandora (Pagellus erythrinus) in the Bay of Kastela. Acta Adriatica, 14, 3–40. Karpouzi, V.S. & Stergiou, K.I. (2003) The relationship between mouth size and shape and body length for 18 species of marine fishes and their trophic implications. Journal of Fish Biology, 62, 1353–1365. Køie, M. (1991) Aspects of the morphology and life cycle of Lecithocladium excisum (Digenea, Hemiuridae), a parasite of Scomber spp. International Journal for Parasitology, 21, 597-602. Køie (1992) Life cycle and structure of the fish digenean Brachyphallus crenatus (Hemiuridae). Journal of Parasitology, 78, 338-343. Køie, M. (1995) The life-cycle and biology of Hemiurus communis Odhner, 1905 (Digenea, Hemiuridae). Parasite, 2, 195-202. Lafferty, K. & Holt, R. (2003). How should environmental stress affect the population dynamics of disease? Ecology Letters, 6, 654-664. Lafferty, K.D., Shaw, J.C. & Kuris, A.M. (2008) Reef fishes have higher parasite richness at unfished Palmyra Atoll compared to fished Kiritimati Island. EcoHealth, 5, 338-345. Lafferty, K.D, Dobson, A.P. & Kuris, A.M. (2006) Parasites dominate food web links. Proceedings of the National Academy of Sciences of the United States of America, 103, 11211–11216 Loot, G., Aldana, M. & Navarrete, S. (2005) Effects of human exclusion on parasitism in intertidal food webs of central Chile. Conservation Biology, 19, 203-212.

85 Marcogliese, D., Gendron, A., Plante, C., Fournier, M. & Cyr, D. (2006) Parasites of spottail shiners (Notropis hudsonius) in the St. Lawrence River: effects of municipal effluents and habitat. Canadian Journal of Zoology, 84, 1461-1481. Massutí, E. & Moranta, J. (2003) Demersal assemblages and depth distribution of elasmobranches from the continental shelf and slope off the Balearic Islands (western Mediterranean). ICES Journal of Marine Science, 60, 753-766. McCallum, H., Gerber, L. & Jani, A. (2005) Does infectious disease influence the efficacy of marine protected areas? A theoretical framework. Journal of Applied Ecology, 42, 688-698. Mouffok, S., Massutí, E., Boutiba, Z., Guijarro, B., Ordines, F. & Fliti, K. (2008) Ecology and fishery of the deep-water shrimp, Aristeus antennatus (Risso, 1816) off Algeria (south-western Mediterranean). Crustaceana, 81, 1177-1199. Noble, E.R. (1972) Parasites of some marine plankton as indicators of their hosts. Transactions of the American Microscopical Society, 91, 90-91. Ordines, F., Massutí, E., Moranta, J., Quetglas, A., Guijarro, B. & Fliti, K. (2011) Balearic Islands vs Algeria: two nearby western Mediterranean elasmobranch assemblages with different oceanographic scenarios and fishing histories. Scientia Marina, 75, 707-717. Pérez-del-Olmo, A., Fernández, M., Gibson, D. I., Raga, J. A. & Kostadinova, A. (2007) Descriptions of some unusual digeneans from Boops boops L. (Sparidae) and a complete checklist of its metazoan parasites. Systematic Parasitology, 66, 137-158. Pérez-del-Olmo, A., Fernández, M., Raga, J.A., Kostadinova, A. & Poulin, R. (2008) Halfway up the trophic chain: development of parasite communities in the sparid fish Boops boops. Parasitology, 135, 257-268. Pérez-del-Olmo, A., Fernández, M., Raga, J. A., Kostadinova, A. & Morand, S. (2009). Not everything is everywhere: Similarity-decay relationship in a marine host-parasite system. Journal of Biogeography, 36, 200–209. Rebecq, J. (1965) Considérations sur la place des trématodes dans le zooplancton marin. Annales de la Faculté des Sciences de Marseille, 38, 61-84. Rogers, S.I., Maxwell, D., Rijnsdorp, A.D., Damm, U. & Vanhee, W. (1999) Fishing effects in northeast Atlantic shelf seas: patterns in fishing effort, diversity and community structure. IV. Can comparisons of species diversity be used to assess human impacts on demersal fish fauna. Fisheries Research, 40, 135-152. Rózsa, L., Reiczigel, J. & Majoros, G. (2000) Quantifying parasites in samples of hosts. Journal of Parasitology, 86, 228–232.

86 Rueda, J.L. & Salas, C. (2003) Seasonal variation of a molluscan assemblage living in a Caulerpa prolifera meadow within the inner Bay of Cádiz (SW Spain). Estuarine Coastal and Shelf Science, 57, 909-918. Sánchez, P., Demestre, M. & Martín, P. (2004) Characterisation of the discards generated by bottom trawling in the northwestern Mediterranean. Fisheries Research, 67, 71-80. Sasal, P., Faliex, E. & Morand, S. (1996) Parasitism of Gobius bucchichii Steindachner, 1870 (Teleostei, Gobiidae) in protected and unprotected marine environments. Journal of Wildlife Diseases, 32, 607-613. Sasal, P., Desdevises, Y., Durieux, E., Lenfant, P. & Romans, P. (2004) Parasites in marine protected areas: success and specificity of monogeneans. Journal of Fish Biology, 64, 370-379. Stergiou, K.I. & Karpouzi, V.S. (2002) Feeding habits and trophic levels of Mediterranean fish. Reviews in Fish Biology and Fisheries, 11, 217-254.

Valle, C., Bayle-Sempere, J.T. & Ramos-Esplá, A.A. (2003) Aproximación multiescalar al estudio de la ictiofauna del litoral rocoso de Ceuta (España). Boletín Instituto Español de Oceanografía, 19, 419-431. Ward, J. & Lafferty, K.D. (2004) The elusive baseline of marine disease: are diseases in ocean ecosystems increasing? PLoS Biology, 2, 542-547. Wood, C.L., Lafferty, K.D. & Micheli, F. (2010) Fishing out marine parasites? Impacts of fishing on rates of parasitism in the ocean. Ecology Letters, 13, 761-775.

87 Figure legend

Fig. 1. Landings of Boops boops registered (in tonnes) between 2007 and 2010 at the ports of Oran in Algeria (red bars) and Santa Pola in Spain (blue bars). Inset: Total national landings of B. boops (in tonnes) of Algeria (red bars) and Spain (blue bars) for the period 2000-2008. Sources: Ministère de la Pêche et des Ressources Halieutiques; Direction de la Pêche et des Ressources Halieutiques (DPRH, Oran); Cofradía de Pescadores de Santa Pola; and FAO-GFCM Data Base (last accessed on 5.10.2011; http://www.gfcm.org/gfcm/topic/17105/en).

Fig. 2. Prevalence of the eight common parasite species in Boops boops in Santa Pola Bay and the Gulf of Oran. Significant differences indicated with stars (*p<0.05; **p<0.01; ***p<0.001).

Fig. 3. Non-metric multidimentional scaling ordination of parasite component communities in Boops boops (Bray-Curtis similarity based on abundance data) sampled at Santa Pola Bay (triangles) and Gulf of Oran (squares).

Fig. 4. Graphical representation of Random Forest classification matrix for the parasite infracommunities in Boops boops. NF, non-fished (Santa Pola Bay); F, fished (Gulf of Oran) populations.

88 Table 1. Parasites in B. boops at the Bay of Santa Pola and the Gulf of Oran. Prevalence (P %) and mean abundance (± standard deviation, SD) are given separately for the samples collected during the warm and cold seasons. P-values from contrasts in prevalence (Fischer's exact test) and abundance (GLM with factors locality and season and fish standard length as a covariate).

Season Warm Cold Santa Pola Gulf of Oran Significance of Santa Pola Gulf of Oran Significance of differences differences Parameter P MA ± SD P MA ± SD P MA P MA ± SD P MA ± SD P MA (%) (%) (%) (%) Monogenea Microcotyle erythrini 67.9 2.23 ± 2.88 16.7 0.43 ± 1.13 0.0001 0.003 16.1 0.70 ± 2.85 21.7 0.53 ± 1.19 ns ns Cyclocotyla bellones 2.4 0.02 ± 0.02 - - - - 7.1 0.07 ± 0.26 - - - - Pseudaxine trachuri 8.3 0.13 ± 0.51 - - - - 5.4 0.05 ± 0.23 - - - - Digenea Aphanurus stossichii 92.9 5.74 ± 9.37 53.3 1.27 ± 1.73 0.0001 0.0001 76.8 4.89 ± 5.28 31.7 0.68 ± 1.21 0.0001 0.0053 Bacciger israelensis 88.1 10.98 ± 12.68 73.3 3.03 ± 4.78 0.023 0.0001 98.2 13.79 ± 14.97 40.0 1.67 ± 3.08 0.0001 0.0001 Hemiurus communis 85.7 11.29 ± 18.05 48.3 1.0 ± 1.28 0.0001 0.0001 14.3 0.46 ± 2.54 45.0 0.65 ± 0.84 0.0001 ns Lecithocladium excisum 28.6 0.43 ± 0.85 46.7 1.02 ± 1.37 0.035 0.007 30.4 0.57 ± 1.17 26.7 0.37 ± 0.69 ns ns Lepocreadium album - - 20.0 0.33 ± 0.77 - - - - 15.0 0.17 ± 0.42 - - Robphildollfusium martinezgomezi 3.6 0.08 ± 0.56 - - - - 1.8 0.02 ± 0.13 - - - - Tetrochetus coryphaenae 4.8 0.06 ± 0.28 - - - - 7.1 0.20 ± 0.98 - - - - Accacladium serpentulum 3.6 0.04 ± 0.19 ------Arnola microcirrus 1.2 0.01 ± 0.11 ------Magnibursatus bartolii 1.2 0.01 ± 0.11 ------Opecoeliidae gen. sp. 1.2 0.01 ± 0.11 ------Derogenes varicus ------1.8 0.02 ± 0.13 - - - - Prosorhynchus crucibulum met. 4.8 0.46 ± 2.94 na na - - 3.6 0.30 ± 1.73 na na - - Stephanostomum euzeti met. 17.9 0.55 ± 2.08 na na - - 17.9 0.29 ± 0.73 na na - - Stephanostomum cesticillum met. - - na na - - 3.6 0.05 ± 0.30 na na - - Tormopsolus sp. 2.4 0.02 ± 0.15 na na - - 3.6 0.07 ± 0.42 na na - -

89 Table 1. Continued.

Season Warm Cold Santa Pola Gulf of Oran Significance of Santa Pola Gulf of Oran Significance of differences differences Parameter P MA ± SD P MA ± SD P MA P MA ± SD P MA ± SD P MA (%) (%) (%) (%) Renicolid metacercariae - - na na - - 1.8 0.02 ± 0.13 na na - - Digenean metacercariae pooled 22.6 1.04 ± 3.55 36.7 0.88 ± 1.62 ns ns 28.6 0.73 ± 2.18 20.0 0.33 ± 0.14 ns ns Cestoda Scolex pleuronectis larva 23.8 0.30 ± 0.60 61.7 7.50 ± 12.55 0.0001 0.0001 25.0 1.30 ± 3.64 40.0 2.15 ± 6.58 ns ns Nematoda Hysterothylacium aduncum larva 51.2 0.92 ± 1.24 25.0 0.65 ± 1.31 0.002 ns 48.2 0.93 ± 1.32 35.0 0.68 ± 1.11 ns ns Anisakis simplex sensu lato larva 11.9 0.14 ± 0.17 - - - - 8.9 0.09 ± 0.29 - - - - Camallanus sp. 1.2 0.01 ± 0.11 ------Cuculanellus sp. 1.2 0.01 ± 0.11 ------Pseudocapillaria adriatica ------1.8 0.02 ± 0.13 - - - - Acanthocephala Neoechinorhynchus agilis 1.2 0.01 ± 0.11 ------Crustacea Ceratothoa oestroides 1.2 0.10 ± 0.87 11.7 0.05 ± 0.64 - - 3.6 0.04 ± 0.19 5.0 0.08 ± 0.38 - - Naobranchia cygniformis 15.5 0.17 ± 0.41 - - - - 8.9 0.13 ± 0.47 - - - - Overall prevalence (%) 100 91.7 100 88.3 Component community richness Infracommunity richness - 5.06 ± 1.51 - 3.93 ± 1.91 - 0.0006 - 3.71 ± 1.34 - 2.80 ± 1.88 - 0.014 Infracommunity abundance - 33.54 ± 24.55 - 16.33 ± 13.78 - 0.0001 23.88 ± 16.7 - 7.32 ± 8.09 - 0.0001

Table 2. Results of generalized linear model on abundance of the common parasites and the richness and abundance of parasite infracommunities in Boops boops at Santa Pola Bay and the Gulf of Oran.

Species/Effect Fish Locality Season Locality standard × Season length A. stossichii Wald χ2* 1.724 47.597 2.419 1.752 P 0.1892 <0.0001 0.120 0.1857 B. israelensis Wald χ2 0.014 57.570 2.846 8.404 P 0.9043 <0.0001 0.0916 0.0037 H. communis Wald χ2 70.894 1.120 8.483 10.573 P <0.0001 0.2898 0.0036 0.0011 L. excisum Wald χ2 0.044 1.149 2.007 5.909 P 0.8343 0.2838 0.1566 0.0151 S. pleuronectis Wald χ2 3.142 19.138 0.749 6.746 P 0.0763 <0.0001 0.3867 0.0094 H. aduncum Wald χ2 0.563 2.513 0.006 0.237 P 0.4529 0.1129 0.9392 0.6263 M. erythrini Wald χ2 15.151 1.940 7.929 6.942 P <0.0001 0.1637 0.0049 0.0084 Digenean metacercariae Wald χ2 0.332 0.005 2.850 1.800 P 0.5647 0.9447 0.0914 0.1797 Infracommunity richness Wald χ2 0.171 21.998 22.562 1.041 P 0.6794 <0.0001 <0.0001 0.3076 Infracommunity abundance Wald χ2 2.635 92.497 18.763 10.241 P 0.1045 <0.0001 <0.0001 0.0014 *Df = 1 for all χ2tests.

Fig. 1 1400 8000

7000

6000 1200 5000 4000 3000 1000 2000 1000

Spain 0 Algeria 2000 2001 2002 2003 2004 2005 2006 2007 2008

800

600

400

200 Santa Pola 0 Oran 2007 2008 2009 2010

Fig. 2 100 *** 90 ***

50 ** *** ***

Prevalence (%) 30

10 0 A. sto B. isr H. com H. adu M. ery S. ple L. exc Dmet

Fig. 3

Fig. 4

93 CHAPTER EIGHT

CONCLUSIONS

The present study applied both descriptive and quantitative comparative approaches to the parasitological examination of Sardina pilchardus and Boops boops in the Gulf of Oran and provided, for the fisrt time, data on the composition of the fauna and the structure of parasite communities in these hosts along Algerian coasts of the western Mediterranean.

The following conclusions can be drawn as a result of the present study:

8.1. The metazoan parasite fauna of S. pilchardus in the Gulf of Oran is relatively species-rich considering the trophic level and the diet of this host. It comprises nine helminth taxa: Aphanurus virgula, A. stossichii, Hemiurus luehei, Parahemiurus merus, Lecithaster confusus, Pronoprymna ventricosa, Scolex pleuronectis larva, Hysterothilacium aduncum larva and Anisakis sp. larva. S. pilchardus is a new host record of A. virgula and this is the first record of the species from the western Mediterranean.

8.2. The metazoan parasite fauna of B. boops in the Gulf of Oran comprises 12 taxa (11 helminths and one isopod): Microcotyle erythrini, Aphanurus stossichii, Hemiurus communis, Lecithocladium excisum, Bacciger israelensis, Lepocreadium album, Prosorhynchus crucibulum met., Tormopsolus sp., Stephanostomum sp. met., Scolex pleuronectis larva, Hysterothylacium aduncum larva and Ceratothoa oestroides. The present study represents the first record of L. album in B. boops in the western Mediterranean, the first record of metacercariae of the genus Tormopsolus and the second record of metacercariae of P. crucibulum in B. boops from the Mediterranean.

8.3. All parasite species found in S. pilchardus and B. boops are recorded for the first time in Algeria.

8.4. The detailed morphological examination carried out for nine trematode species provided new data that expand the knowledge of the morphometric variation of five trematodes in S. pilchardus (A. virgula, A. stossichii, P. merus, L. confusus and P. ventricosa) and four

94 trematode parasites of B. boops (A. stossichii, H. communis, B. israelensis and L. album). This study also provided the first detailed description of A. stossichii from its type-host, S. pilchardus, and the first description of P. merus from this host.

8.5. The complete checklist of helminth parasites of S. pilchardus throughout its distributional range (Mediterranean basin and North East Atlantic), developed during the course of the study, contains information for a total of 39 taxa (2 monogeneans, 16 digeneans, 4 cestodes, 15 larval nematodes and two acanthocephalans) and 104 host-parasite-area records.

8.6. This study represents the first description of the composition, structure and diversity of parasite communities in S. pilchardus. The results of the comparative analyses carried out at the infracommunity and component community level revealed that helminth communities in this host are characterised by low richness, abundance, diversity, similarity and high dominance of a single species. The three dominant species identified (P. ventricosa, A. stossichii and H. luehei) contributed substantially to the richness and abundance of infracommunities, and the high similarity within component communities. The lack of significant correlation between fish size and parasite abundance and the lack of significant seasonal effects on community structure characterise the studied host-parasite system in the Gulf of Oran as largely homogeneous.

8.7. Comparative approaches to the prevalence, abundance and community structure of parasites in B. boops from Santa Pola Bay and the Gulf of Oran, characterised by a contrasting pattern of fishing of this host, suggested a distinct compositional segregation with only eight, out of 29 parasite species, in common for the two localities. This was supported by the substantially higher richness and abundance of the parasites and the different structure of parasite communities sampled at Santa Pola Bay. The significant consistent differences revealed for the prevalence of the key parasites using B. boops as the main host, and the richness, abundance and structure of parasite infracommunities may thus reflect the contrasting patterns of exploitation of the populations of this fish host.

95 CHAPTER NINE

REFERENCES

Abad, R. & Giráldez, A. (1990) Descripción de la pesca de cerco en la región Surmediterránea. Inf. Tec. lnst. Esp. Oceanog., 86, 18. Abdul Malak, D. et al. (2011) Overview of the Conservation Status of the Marine Fishes of the Mediterranean Sea. Gland, Switzerland and Malaga, Spain: IUCN. vii + 61pp. Akmirza, A. (1998) Parasites in bogue (Boops boops Linnaeus,1758). Ege University, Journal of Fisheries and Aquatic Sciences,15, 183-198. Akmirza, A. (2000) Seasonal distribution of parasites detected in fish belonging to the sparidae family found near Gokçeada. Acta Parasitologica Turcica, 24, 435-441. Álvarez, F. (1980) Growth studies of Sardina pilchardus (Walb) in Galicia waters (N. W. Spain). ICES C.M. 1981/H, 29, 1-11. Anato, C.B., Ktari, M.H. & Dossou, C. (1991) La parasitofaune d’un métazoaire Boops boops (Linne, 1758), poisson téléostéen Sparidae des côtes Tunisiennes. Oebalia. International Journal of Marine Biology and Oceanography, 17, 259-266. Anderson, R.C. (2000) Nematodes parasites of vertebrates. Their development and transmission (second edition). CABI Publishing, Wallingford, Oxon UK, 650 pp. Aoudjit, N. (2001) Contribution à l'étude de quelques paramètres de la reproduction de la bogue (Boops boops, 1785) et son utilisation comme indicateur biologique de la pollution par les métaux lourds (Zinc, Fer, Nickel, Cuivre et Plomb) dans la baie d'Oran. Thèse de Magistère. P 219. Balcells, R. (1953) Sur des Isopodes parasites des poissons. Vie et Milieu, 4, 547-552. Bandarra, N.M., Batista, I., Nunes, M.L., Empis, J.M. & Christie, W.W. (1997) Seasonal changes in lipid composition of sardine (Sardina pilchardus). Journal of Food Science, 62, 40-42. Bartoli, P. (1987) Les trématodes digénétiques parasites des poissons sparidés de la Réserve Naturelle de Scandola. Travaux Scientifiques du Parc Naturel Régional et des Réserves Naturelles de Corse, 10, 1-158. Bartoli, P., Gibson, D. I. & Bray, R.A. (2005) Digenean species diversity in teleost fish from a nature reserve off Corsica, France (Webstern Mediterranean), and a comparison with other Mediterranean regions. Journal of Natural History, 39, 47-70. Bás, C., Macpherson, E. & Sardá, F. (1989) Peces y pescadores. Los niveles tróficos explotables.ln: El Mediterra'neo Occidental, Margalef, R. (ed.). Omega, pp. 298-319. 96 Baudouin, M. (1905) Les parasites de la sardine. Revue Scientifique, 3 (23), 715-722. Bauchot, M. L. & Hureau, J. C. (1986) Sparidae. In: Whitehead P.J.P., Bauchot M.-L., Hureau J.-C., Nielsen J. & Tortonese E. (Eds.) Fishes of the North-eastern Atlantic and the Mediterranean. Vol. II. Paris: Unesco, pp. 883-907. Bedairia, A. & Djebbar, A.B. (2009) A preliminary analysis of the state of exploitation of the sardine, Sardina pilchardus (Walbaum, 1792), in the gulf of Annaba, East Algerian. Animal Biodiversity and Conservation, 32, 2. Becheikh, S., Raibaut, A., Euzet, S., & Ben Hassine, O.K. (1994) Etude biosystématique de deux populations de Téléostéens (Sardina pilchardus) et de leurs Copépodes parasites (Peroderma cylindricum) sur les côtes tunisiennes. Parasite, 1, 279-282. Becheikh, S., Rousset, V., Maamouri, F., Ben Hassine, O.K. & Raibaut, A. (1997) Pathological effects of Peroderma cylindricum (Copepoda: Pennellidae) on the kidneys of its pilchard host, Sardina pilchardus (Osteichthyes: Clupeidae), from Tunisian coasts. Diseases of Aquatic Organisms, 28, 51-59. Belghyti, D., Mouhssin, M., Mokhtar, N., El Kharrim, K., Morand, S. & Bouchereau, J-L. (1997) Systématique de deux nouveaux copépodes parasites de la sardine (Sardina pilchardus Walbaum 1792) de l'Atlantique marocain (Kénitra-Mehdia). Actes de l’Institut Agronomique et Vétérinaire Hassan II (Maroc), 17, 173-180. Bell, J.D. & Harmelin-Vivien, M.I. (1983) Fish fauna of French Mediterranean Posidonia oceanica seagrass meadows. 2. Feeding habits. Tethys, 11, 1-14. Ben Hassine, O.K., Raibaut, A., Ben Souissi, J. & Rousset, V. (1990) Morphologie de Peroderma cylindricum Heller, 1865, Copépode parasite de la Sardine, Sardina pilchardus (Walbaum, 1792) et quelques aspects de son écologie dans les eaux côtières tunisiennes. Annales des Sciences Naturelles 2001, Paris (Ser 13), 11, 9-16. Ben Souissi, J. & Ben Hassine, O.K. (1991) Action pathogène de Peroderma cylindricum Heller, 1865 (Copépode parasite) sur la condition et le développement des gonades de Sardina pilchardus (Walbaum, 1792) des côtes tunisiennes. Cahiers de Biologie Marine, Roscoff, 32, 234. Berland, B. (1991) Hysterothylacium aduncum (Nematoda) in fish. In: International council for the exploration of the sea. Sindermann, C.J. & Maurin, C. Bouchereau, J.L. (1981) Contribution à l’étude de la biologie et de la dynamique exploitée de Sardina pilchardus (Walbaum, 1792) dans la baie d’Oran (Algérie). Thèse Doctorale 3ème cycle, Univ. Aix– Marseille II. Boutiba, Z. (1992) Les mammifères marins d’Algérie. Statut, Répartition, Biologie et Ecologie. Thèse Doct. Etat. 575 pp. 97 Brahmi, B., Bennoui, A. & Oualiken, A. (1998) Estimation de la croissance de la sardine (Sardina pilchardus, Walbaum, 1792) dans la région centre de la côte Algérienne. Marine populations dynamics, 35. Brinkmann, A. (1966) Some trematodes from marine fishes in the waters of Rhodes. Arbok for Universitetet i Bergen, Mat.-Naturv. Serie, 10, 3-13 Bush, A.O., Lafferty, K.D., Lotz, J.M. & Shostak, A.W. (1997) Parasitology meets ecology in its own terms: Margolis et al. revisited. Journal of Parasitology, 83, 575-583. Caddy, J.F. (1997) Review of the state of world fishery resources: Marine fisheries. B. Regional reviews. 5. Mediterranean and Black Sea, FAO Fisheries Circular, No 920, FAO, Rome. CIRCE. Climate Change and Impact Research: the Mediterranean Environment. Deliverable D11.5.4. (http://www.circeproject.eu/). Clarke, K.R. & Gorley, R.N. (2006) PRIMER v6: user Manual/Tutorial. PRIMER-E Ltd: Plymouth. Coll, M., et al. (2010) The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats. PLoS ONE, 5 (8), e11842 Cook, J.-M., Blanc, G., & Escoubet, P. (1981) Parasites et poissons d’aquariums méditerranés. Vie Marine, 3, 139-144. Cordero del Campillo, M., Ordóñez, L.C. & Feo, A.R. (1994) Indice-Catálogo de Zooparásitos Ibéricos. León: Universidad de León, pp. 5-650. Cordero del Campilo, M. et al. (1975) Indice-catálogo de zooparásitos ibéricos. II. Trematodos. Barcelona: Consejo Superior de Investigaciones Científicas, pp. 75-117. Costa, G. & Biscoito, M. (2003) Helminth parasites of some coastal fishes from Madeira, Portugal. Bulletin of the European Association of Fish Pathologists, 23, 281-286. Demestre, M., Sanchez, P. & Abell, O.P. (2000) Demersal fish assemblages and habitat characteristics on the continental shelf and upper slope of the north-western Mediterranean. Journal of the Marine Biological Association of the United Kingdom, 80, 981-988. Derbal, F. & Kara, M.H. (2001) Inventaire des poissons des côtes de l’Est algérien. Rapp. Comm. Int. Mer Médit., 36, 258. Derbal, F. & Kara, M.H. (2008) Composition du régime alimentaire du bogue Boops boops (Sparidae) dans le golfe d’Annaba (Algérie). Cybium, 32, 325-333. Dimitrov, G. I. (1991) Trematodes of the superfamily Hemiuroidea Looss, 1899 in fishes from the Bulgarian Black Sea coast. Khelmintologiya, 31, 31-44 (In Bulgarian).

98 Dimitrov, G.I. & Bray, R.A. (1994) A redescription and a new geographical record in the Black Sea of Bacciger israelensis Fischthal, 1980 (Trematoda: Fellodistomidae). Folia Parasitologica, 41, 75-79. Djabali, F., Brahmi, B. & Maamass, M. (1993). Poissons des côtes algériennes. Pelagos (NS), 1-215. Djabali, Y., Mouhoub, R. & Hemida, F. (1987) Résultats des travaux réalisées sur les stocks de sardines et de anchois des cotes algéroises. In: Evaluation des stocks dans les divisions statistiques Baléares et Golfe du Lion: Rapport de la cinquième consultation technique: Fuengirola, Espagne, 19-23 October, 1987; C.G.P.M. FAO Raport No. 395, pp. 112-120. Erzini, K., Bentes, L., Lino, P.G., Ribeiro, J., Coelho, R., Monteiro, P., Correia, C. & Gonçalves, J.M. (2001) Reproductive aspects of seven sparid fishes from the southern coast of Portugal (Algarve). In: Tenth European Congress of Ichthyology-ECI X, Prague 3-7 September 2001. Euzet, L. (1959) Recherches sur les cestodes tétraphyllides des sélaciens des cotes de France. Thèse présentées à la Faculté des Sciences l’Université de Montpellier, Montpellier (1956); Fernández, I., Moyano, F.J., Díaz, M. & Martínez, T. (2001) Characterisation of α-amilase activity in five species of Mediterranean sparid fishes (Sparidae, Teleostei). Journal of Experimental Marine Biology and Ecology, 262, 1-12. Fischthal, J.H. (1980) Some digenetic trematodes of marine fishes from Israel’s Mediterranean coast and their zoogeography, especially those from Red Sea immigrant fishes. Zoologica Scripta, 9, 11-23. Fischthal, J.H. (1982) Additional records of digenetic trematodes of marine fishes from Israel’s Mediterranean coast. Proceedings of the Helminthological Society of Washington, 49, 34-44. Freon, P. & Misund, O.A. (1999). Dynamics of Pelagic Fish Distribution and Behaviour: Effects on Fisheries and Stock Assessment. Fishing New Books, Oxford. Froese, R. & Pauly, D. (Eds) (2011) FishBase. World Wide Web electronic publication. www.fishbase.org. Furnestin, A. (1943) Contribution à l’étude biologique de la Sardine Atlantique (Sardina pilchardus) Rev. Trav. Off. Pêche Maritime, 13, 221-386. García-Rubies, A. & Zabala, M. (1990) Effects of total fishing prohibition on the rocky fish assemblages of Medes Islands marine reserve (NW Mediterranean). Scientia Marina, 54, 317-328. 99 Garrido, S., Ben-Hamadou, R., Oliveira, P. B., Cunha, M.E., Chícharo, M.A. & Van der Lingen, C.D. (2008) Diet and feeding intensity of sardine Sardina pilchardus: correlation with satellite-derived chlorophyll data. Marine Ecology Progress Series, 354, 245-256. Georgiev, B.B., Biserkov, V.Y. & Genov, T. (1986) In toto staining method for cestods in iron acetocarmine. Helminthologia, 23, 279-281. GFCM (2011a) General Fisheries Commission for the Mediterranean. Scientific Advisory Committee, Session 13, Inf. 8. Draft report of the 12th session of the SAC sub- committee on stock assessment (SCSA), Saint George’s Bay Malta, 28 November-3 December 2010. GFCM (2011b) General Fisheries Commission for the Mediterranean. Scientific Advisory Committee, Session 13, Inf. 21. Report of the SCSA working group on stock assessment of small pelagic species, Campobello di Mazara, Italy, 1-6 November 2010. Gibson, D.I. & Bray, R.A. (1986) The Hemiuridae (Digenea) of fishes from the northeast Atlantic. Bulletin of the British Museum (Natural History) (Zoology), 51, 1-125. Girardin, M. (1981) Pagellus erythrinus (Linnaeus, 1758) et Boops boops (Linnaeus,1758) (Pises, Sparidae) du Golfe du Lion. Ecobiologie, prises commerciales et modèles de gestion. PhD thesis. University of Science and Thecniques du Languedoc, Academy of Montpellier, 295 pp. Harmelin, J.-G. (1987) Structure et variabilité de l’ichtyofaune d’une zone rocheuse protégée en Méditerranée (Parc national de Port-Cros, France). Marine Ecology, 8, 263-284. Jensen, K. & Bullard, S.A. (2010) Characterization of a diversity of tetraphyllidean and rhinebothriidean cestode larval types, with comments on host associations and life- cycles. International Journal for Parasitology, 40, 889-910. Joyeux, C. & Baer, J.G. (1936) Cestodes. Fauna de France, Paris, 30, 613 pp. Justine, J.-L. (1985) Etude ultrastructurale comparée de la spermiogénèse des Digènes et des Monogènes (Plathelminthes). Relations entre la morphologie du spermatozoıde, la biologie de la fécondation et la phylogénie. Thèse d’Etat, Université des Sciences et Techniques du Languedoc (Montpellier II), 231 pp. Kallianiotis, A., Sophrondis, K., Vidoris, P. & Tselepides, A. (2000) Demersal fish hand megafaunal assemblages on the Cretan continental shelf and slope (NE Mediterranean): Seasonal variation in species density, biomass and diversity. Progress in Oceanography, 46, 429-455.

100 Karpouzi, V.S. & Stergiou, K.I. (2003) The relationship between mouth size and shape and body length for 18 species of marine fishes and their trophic implications. Journal of Fish Biology, 62, 1353-1365. Kerfouf, A., Amar, Y. & Boutiba, Z. (2007) Distribution of macrobenthos in the coastal waters in the Gulf of Oran (Western Algeria). Pakistan Journal of Biological Sciences, 10, 899-904. Kostadinova, A., Gibson, D.I., Balbuena, J.A., Power, A.M., Montero, F.E., Aydogdu, A. & Raga, J.A. (2004) Redescriptions of Aphanurus stossichii (Monticelli, 1891) and A. virgula Looss, 1907 (Digenea: Hemiuridae). Systematic Parasitology, 58, 175-184. Krebs, C.J. (1989) Ecological Methodology. HaprerCollins Publishers, New York. 654 pp. Ktari, M.H. & Abdellnouleh, A. (1980) Note sur la présence et les effets du copépode Peroderma cylindricum Heller, 1868, parasite de la sardine Sardina pilchardus (Walbaum, 1792) des côtes tunisiennes. Bulletin. Station Océanographique de Pêche de Salammbô , 7, 103 112. Linde, M., Palmer, M. & Gómez-Zurita, J. (2004) Differential correlates of diet and phylogeny on the shape of the premaxilla and anterior tooth in sparid fishes (Perciformes: Sparidae). Journal of Evolutionary Biology, 17, 941-952. Lleonart, J. & Maynou, F. (2003) Fish stock assessments in the Mediterranean: state of the art. Scientia Marina, 67 (Suppl. 1), 37-49. Lloret, J. (2010) Human health benefits supplied by Mediterranean marine biodiversity. Marine Pollution Bulletin, 60, 1640-1646. Looss, A. (1907). Zur Kenntnis der Distomenfamilie Hemiuridae. Zoologischer Anzeiger, 31, 585-620. López-Román, R. & Guevara Pozo, D. (1973) Especies de la familia Microcotylidae (Monogenea) halladas en teleosteos marinos de la costa de Granada. Revista Ibérica de Parasitología, 33, 197-233. López-Román, R. & Guevara Pozo, D. (1974) Incidencia de parasitación por Digenea de algunos teleosteos marinos del Mar de Alborán. Revista Ibérica de Parasitología, 34, 147. López-Román, R. & Guevara Pozo, D. (1976) Cyclocotyla bellones Otto, 1821 (Monogenea) presente en Meinertia oestreoides en cavidad bucal de Boops boops en aguas del Mar de Alborán. Revista Ibérica de Parasitología, 36, 135-138. Lozano, C., Ubeda, J.M., De Rojas, M., Ariza, C. & Guevara, D.C. (2001) Estudio de digenidos de pèces marinos del sur de la Peninsula Iberica. Research and Reviews in Parasitology, 61, 103-116. 101 Monticelli, F. S. (1891). Osservazioni intorno ad alcune forme del gen. Apoblema Dujardin. Atti della Reale Accademia della Scienze, Torino, 26, 496-524. Mouhoub, R. (1986) Contribution à l’étude de la biologie et de la dynamique de la population exploitée de la sardine Sardina pilchardus (Walbaum, 1792) des côtes algéroises. Thèse de Magistère, U.S.T.H.B. Naidenova, N.N. & Mordvinova, T.N. (1997) Helminth fauna of Mediterranean sea fish upon the data of the IBSSs expeditions (1959-1973). Ekologiya Morya, 46, 69-74 (In Russian). Orecchia, P. & Paggi, L. (1978) Aspetti di sistematica e di ecologia degli elminti parassiti di pesci marini studiati presso l’Istituto di Parassitologia dell’Università di Roma. Parassitologia, 20, 73-89. Papoutsoglou, S.E. (1976) Metazoan parasites of fishes from Saronicos Gulf, Athens - Greece. Thalassographica, 1, 69-102. Parona, C. & Perugia, A. (1890) Nuove osservazioni sul’Amphibdella torpedinis Chatin. Annali del Museo Civico de Storia Naturale di Genova, Ser. 2, 9, 363-367. Parrish, R. H., Serra, R. & Grant, W.S. (1989) The monotypic sardines, Sardina and Sardinops: their taxonomy, distribution, stock structure, and zoogeography. Canadian Journal of Fisheries and Aquatic Sciences, 46, 2019-2036. Parukhin, A.M. (1966) [On the species composition of the helminth fauna of fishes in the South Atlantic.] Materialy Nauchnoi Konferentsii Vsesoyuznogo Obshchestva Gelmintologov, 3, 219-222 (In Russian). Parukhin, A.M. (1976) [Parasitic worms in food fishes of the Southern Seas.] Kiev: Naukova Dumka, 183 pp. (In Russian). Parukhin, A.M., Naidenova, N.N. & Nikolaeva, V.M. (1971) The parasite fauna of fishes caught in the Mediterranean Sea. In: Vodjanichkiy, V.A. (Ed.) [Expeditionary Investigations in the Mediterranean Sea in May – July, 1970.] Naukova Dumka, Kiev, pp. 64-87. (In Russian). Pérez-del Olmo, A., Fernández, M., Gibson, D.I., Raga, J.A. & Kostadinova, A. (2007) Descriptions of some unusual digeneans from Boops boops L. (Sparidae) and a complete checklist of its metazoan parasites. Systematic Parasitology, 66, 137-157. Pérez-del Olmo, A., Fernández, M., Raga, J.A. & Kostadinova, A. (2004) Structure of helminth communities in Boops boops from the NE Atlantic and the Mediterranean. In: IX European Multicolloquium of Parasitology, 18-23 July 2004, Valencia, Spain. Abstracts: p. 567.

102 Pérez-del Olmo, A., Gibson, D.I., Fernández, M., Sanisidro, O., Raga, J.A. & Kostadinova, A. (2006) Descriptions of Wardula bartolii n. sp. (Digenea: Mesometridae) and three newly recorded accidental parasites of Boops boops L. (Sparidae) in the NE Atlantic. Systematic Parasitology, 63, 97–107. Pérez-del-Olmo, A., Fernández, M., Raga, J.A., Kostadinova, A. & Poulin, R. (2008) Halfway up the trophic chain: development of parasite communities in the sparid fish Boops boops. Parasitology, 135, 257-268. Petter, A.J. & Maillard, C. (1988a) Ascarides de Poissons de Méditerranée occidentale. Bulletin du Muséum National d’Histoire Naturelle, 9, 773-798. Petter, A.J. & Maillard, C. (1988b) Larves d’Ascarides parasites de poissons en Méditerranée occidentale. Bulletin du Muséum National d’Histoire Naturelle, serie 4, 10, 347-369. Petter, A.J. & Radujkovic, B.M. (1989) Parasites des poissons marins du Monténégro: Nématodes. Acta Adriatica, 30, 195-236. Petter, A.J., Lébre, G. & Radjukovic, B.M. (1984) Nématodes parasites de poissons Ostéichthyens de l’Adriatique Méridionale. Acta Adriatica, 25, 205-221. Power, A.M., Balbuena, J.A. & Raga, J.A. (2005) Parasite infracommunities as predictors of harvest location of bogue (Boops boops L.): a pilot study using statistical classifiers. Fisheries Research, Amsterdam, 72, 229-239. Radujkovic, B., Orecchia, P. & Paggi, L. (1989) Parasites des poissons marins du Monténégro: Digenes. Acta Adriatica, 30, 137-187. Radujkovic, B.M. & Raibaut, A. (1989) Parasites des poissons marins du Monténégro: liste des espèces de poissons avec leurs parasites. Acta Adriatica, 30, 307-320. Raibaut, A., Ben Hassine, O.K. & Maamoun, K. (1971) Copépodes parasites des poissons de Tunisie (premiére serie). Bulletin Institute National Sciences Technologie Pêche Salammbó, 2, 169-197. Rello, F.J., Adroher, F.J., & Valero, A. (2008) Hysterothylacium aduncum, the only anisakid parasite of sardines (Sardina pilchardus) from the southern and eastern coasts of Spain. Parasitology Research, 104, 117-121. Renaud, F., Romestand, B. & Trilles, J.P. (1980) Faunistique et écologie des métazoaires parasites de Boops boops Linnaeus (1758) (Téléostéen Sparidae) dans le Golfe du Lion. Annales de Parasitologie Humaine et Comparée, 55, 467-476. Rózsa, L., Reiczigel, J. & Majoros, G. (2000) Quantifying parasites in samples of hosts. Journal of Parasitology, 86, 228-232.

103 Ruitton, S., Verlaque, M. & Boudouresque, C.F. (2005) Seasonal changes of the introduced Caulerpa racemosa var. cylindracea (Caulerpales, Chlorophyta) at the northwest limit of its Mediterranean range. Aquatic Botany, 82, 55-70. Saad-Fares, A. & Combes, C. (1992a) Comparative allometry growth of some marine fish digenetic trematodes. Memorias do Instituto Oswaldo Cruz, 87, 233-237. Saad-Fares, A. & Combes, C. (1992b) Abundance/host size relationship in a fish trematode community. Journal of Helminthology, 66, 187-192. Saad-Fares, A. & Maillard, C. (1990) Digenetic trematodes of Lebanese coast fishes: the species complexes Lepocreadium album (Stossich, 1890) and Lepocreadium pegorchis (Stossich, 1900) (Lepocreadiidae). Systematic Parasitology, 17, 87-95. Saad-Fares, A. (1985) Trématodes de poissons des côtes du Liban. Spécificité, transmission et approche populationnelle. Thèse Université des Sciences et Techniques du Languedoc (Montpellier), 434 pp. Sánchez-Jerez, P., Gillanders, B.M., Rodríguez-Ruiz, S. & Ramos-Esplá, A.A. (2002) Effect of an artificial reef in Posidonia meadows on fish assemblage and diet of Diplodus annularis. ICES Journal of Marine Science, 59, S59-S68. Sánchez-Velasco, L. & Norbis, W. (1997) Comparative diets and feeding habits of Boops boops and Diplodus sargus larvae. Two sparid fishes co-ocurring in the northwestern Mediterranean (May 1992). Bulletin of Marine Science, 61, 821-835. Santos, A.T., Sasal, P., Verneau, O., & Lenfant, P. (2006) A method to detect the parasitic nematodes from the family Anisakidae, in Sardina pilchardus, using specific primers of 18 S DNA gene. European Food Research and Technology, 222, 71-77. Sey, O. (1970) Parasitic helminths occurring in Adriatic fishes. Part II. (Flukes and tapeworms). Acta Adriatica, 13, 1-16. Shukhgalter, O.A. (1998) [General characteristics of parasitofauna of European sardine (Sardina pilchardus Walb.) and some aspects of its geographical variability.] In: Fishery biological researches by AtlantNIRO in 1996-1997. Trudy Atlanticheskii Nauchno-Issledovatel’skii Institut, Rybnogo Khozyaitsva i Okeanografii, Kaliningrad, pp. 170-180 (In Russian). Silva, A., Carrera, P., Massé, J.A., Uriarte, D., Santos, M.B., Oliveira, P. B., Soares, E., Porteiro, C. & Stratoudakis, Y. (2008) Geographic variability of sardine growth across the northeastern Atlantic and the Mediterranean Sea. Fisheries Research, 90, 56-69. Silva, A., Santos, M. B. Caneco, B., Pestana, G., Porteiro, C., Carrera, P. & Stratoudakis, Y. (2006) Temporal and geographic variability of sardine maturity at length in the north-

104 eastern Atlantic and the western Mediterranean. ICES Journal of Marine Science, 63, 663-676. Stergiou, K.I. & Karpouzi, V.S. (2002) Feeding habits and trophic levels of Mediterranean fish. Reviews in Fish Biology and Fisheries, 11, 217-254. Tantawy, E.A., & Mahmoud, N.A.M. (1999) Some studies on larval nematodes (Ascarididae) infection in Sardina pilchardus with reference to its public health importance. Egyptian Journal of Agricultural Research, 77, 1371-1384. Tavares, L.E.R., Luque, J.L. & Bicudo, A.J.A. (2005) Community ecology of metazoan parasites of the anchovy Anchoa tricolor (Osteichthyes: Engraulidae) from the coastal zone of the state of Rio de Janeiro, Brazil. Brazilian Journal of Biology, 65, 533-540. Trilles, J.-P. & Raibaut, A. (1971) Aegidae et Cymothoidae parasites de poissons de mer Tunisiens: premiers résultats. Bulletin de l’Institut National Scientifique et Technique d’Océanographie et de Pêche Salambo, 2, 71-86. Trilles, J.-P., Radujkovic, B.M. & Romestand, B. (1989) Parasites des poissons marins du Monténégro: Isopodes. Acta Adriatica, 30, 279-306. Valle, C., Bayle-Sempere, J.T. & Ramos Esplá, A.A. (2001) Estudio multiescalar de la ictiofauna asociada a praderas de Posidonia oceanica (L.) Delile, 1813 en Alicante (sudeste ibérico) Boletín. Instituto Español de Oceanografía, 17, 49-60. Valle, C., Bayle-Sempere, J.T. & Ramos-Esplá, A.A. (2003) Aproximación multiescalar al estudio de la ictiofauna del litoral rocoso de Ceuta (España). Boletín. Instituto Español de Oceanografía, 19, 419-431. Vu Tan Tue (1963) Sur la présence de dents vomériennes et ptérygoïdiennes chez Boops boops (L.) (Pisces, Sparidae), en rapport avec l’isopode phorétique intrabuccal Meinertia. Vie et Milieu, 14, 225-232. Whitehead, P.J.P., Bauchot, M.L., Hureau, J.C., Nielsen, J. & Tortonese, E. (1984) Fishes of the North-eastern Atlantic and the Mediterranean. Vol. II. pp. 780-792. Paris: UNESCO.

105 APPENDIX 1

Results from pairwise comparisons among the six samples from the Gulf of Oran for the prevalence of infection of Sardina pilchardus with parasites

Significance p-values for the pair-wise comparisons (Fisher's exact test in Quantitative Parasitology 3.0). Significant values in bold.

Aphanurus stossichii

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 0.230 July 2006 0.149 1.00 April 2007 1.000 0.592 0.435 June 2007 0.542 1.000 0.435 1.000 September 2007 0.102 0.412 0.430 0.102 0.102

Hemiurus luehei

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 0.769 July 2006 0.781 0.441 April 2007 0.375 0.783 0.193 June 2007 0.375 0.783 0.193 1.000 September 2007 0.539 0.780 0.441 1.000 1.000

Pronoprymna ventricosa

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 0.245 July 2006 0.392 0.799 April 2007 0.245 1.000 0.799 June 2007 0.046 0.592 0.301 0.592 September 2007 0.002 0.040 0.012 0.040 0.035

Parahemiurus merus

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 0.565 July 2006 0.284 1.000 April 2007 1.000 0.565 0.284 June 2007 1.000 0.565 0.284 1.000 September 2007 0.213 0.573 0.590 0.146 0.146

106

Lecithaster confusus

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 - July 2006 0.387 - April 2007 - - - June 2007 - - - - September 2007 - - - -

Scolex pleuronectis larva

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 0.747 July 2006 0.558 0.187 April 2007 0.320 0.747 0.055 June 2007 1.000 1.000 0.419 0.530 September 2007 0.752 0.372 1.000 0.124 0.557

Hysterothylacium aduncum larva

January 2006 March 2006 July 2006 April 2007 June 2007 September 2007 January 2006 March 2006 1.000 July 2006 0.730 0.545 April 2007 0.456 0.331 0.735 June 2007 0.720 0.530 1.000 1.000 September 2007 - - - - -

107 APPENDIX 2

Box-plots for the abundance of the parasites of Sardina pilchardus in the six samples from the Gulf of Oran Aphanurus stossichii

3.0

2.5

2.0

1.5

A. stossichii 1.0

0.5

of Abundance 0.0

-0.5 Mean Mean±SE -1.0 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

Hemiurus luehei

3.0

2.5

2.0

1.5

H. luehei 1.0

0.5 Abundance of Abundance 0.0

-0.5 Mean Mean±SE -1.0 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

108 Pronoprymna ventricosa

P. ventricosa

of Abundance 0

-1 Mean Mean±SE -2 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

Parahemiurus merus

3.0

2.5

2.0

1.5

1.0

0.5

P. merus of Abundance 0.0

-0.5 Mean Mean±SE -1.0 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

109

Scolex pleuronectis larva

S. pleuronectis 2

Abundance of of Abundance -1 -2 Mean Mean±SE -3 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

Hysterothylacium aduncum larva

2.5

2.0

1.5

1.0 H. aduncum

0.5

0.0 Abundance of of Abundance

-0.5

Mean Mean±SE -1.0 Mean±SD Jan 06 Mar 06 Jul 06 Apr 07 Jun 07 Sep 07

110 APPENDIX 3

Anisakis sp. ex Sardina pilchardus from the Gulf of Oran. Scanning electron microphotograph of the anterior extremity

111