AcAdemy of ScienceS of the czech Republic

DracunculoiD anD anGuillicoloiD Parasitic in vertebrates

Ukázka knihy z internetového knihkupectví www.kosmas.cz the publisher thanks the for a financial contribution that made the publication of this book possible.

U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 contents

preface ...... 7 introduction ...... 13 Historical review ...... 17 methods of study of dracunculoid and anguillicoloid nematodes ...... 37 morphology and taxonomical features of dracunculoids and anguillicoloids ...... 48 biology of dracunculoid and anguillicoloid nematodes ...... 63 Pathogenicity and significance of dracunculoids and anguillicoloids ...... 70 list of dracunculoid and anguillicoloid nematodes ...... 77 systematic review of dracunculoid and anguillicoloid nematodes ...... 84 Superfamily dracunculoidea ...... 84 family daniconematidae ...... 86 Genus Daniconema ...... 87 Genus Mexiconema ...... 91 Genus Syngnathinema ...... 97 family ...... 99 Genus Avioserpens ...... 100 Genus ...... 113 family Guyanemidae ...... 152 Subfamily Guyaneminae ...... 152 Genus Guyanema ...... 153 Genus Histodytes ...... 165 Genus Moravecia ...... 167 Genus Pseudodelphis ...... 169 Subfamily travassosneminae ...... 174 Genus Ichthyofilaria ...... 175 Genus Travassosnema ...... 183 family lucionematidae ...... 187 Genus Lucionema ...... 187 family micropleuridae ...... 190 Subfamily micropleurinae ...... 191 Genus Granulinema ...... 191 Genus Kamegainema ...... 196 Genus Micropleura ...... 198 Genus Philonema ...... 212 Genus Protenema ...... 226 Subfamily phlyctainophorinae ...... 229 Genus Phlyctainophora ...... 230 family philometridae ...... 234

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Subfamily Alineminae ...... 235 Genus Alinema ...... 235 Subfamily neophilometroidinae ...... 240 Genus Neophilometroides ...... 240 Subfamily philometrinae ...... 247 Genus Buckleyella ...... 248 Genus Clavinema ...... 250 Genus Dentiphilometra ...... 260 Genus Nilonema ...... 264 Genus Paraphilometroides ...... 267 Genus Philometra ...... 271 Genus Philometroides ...... 420 Genus Rumai ...... 474 Genus Spirophilometra ...... 476 family Skrjabillanidae ...... 477 Subfamily esocineminae ...... 478 Genus Esocinema ...... 478 Subfamily Skrjabillaninae ...... 481 Genus Molnaria ...... 481 Genus Sinoichthyonema ...... 487 Genus Skrjabillanus ...... 490 family tetanonematidae ...... 502 Genus Tetanonema ...... 502 Genus incertae sedis: Lockenloia ...... 504 Superfamily Anguillicoloidea ...... 506 family ...... 506 Genus Anguillicola ...... 506 Genus ...... 511 Host – parasite list ...... 541 pisces (fishes) ...... 541 Amphibia (Amphibians) ...... 575 Reptilia (Reptiles) ...... 576 Aves (birds) ...... 579 mammalia (mammals) ...... 581 references ...... 585 index ...... 618

U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 Preface

the idea of writing the monograph presented here arose from the fact that, until now, no book dealing specifically with the nematodes of the spirurid superfamily dracunculoidea has been published. the only publication providing a survey of all dracunculoids, anguillicoloids and camallanoids known at that time was the book “camallanata of and man and the diseases caused by them” by ivashkin et al. (1971) published in Russian. now, it is rather out of date and the classification system used in it is not accepted by most helminthologists. moreover, many new interesting forms of dracunculoids and anguillicoloids were discovered since, mainly from fishes, which substantially extend the present knowledge about members of these two groups. important new information has also accummulated about the biology, distribution and host–parasite relationships of some of them. despite the fact that dracunculoids represent a large group of important parasites with hosts belonging to all classes of vertebrates including man, their recognition is by far inadequate. Recent morphological, biological and molecular studies of members of the family Anguillicolidae, which has usually been assigned to the dracunculoidea, now show that this small nematode group is phylogenetically distant from other dracunculoids and should be placed in an independent superfamily Anguillicoloidea. Species descriptions of dracunculoids and anguillicoloids, frequently incomplete and often misleading, are scattered in many journals and, to date, there is no monograph about these nematodes enabling their species identification. therefore, i considered it useful to compile the book dealing with these parasites as a whole, in a similar way as my previous book treating the trichinelloids parasitic in cold-blooded vertebrates (moravec 2001a). my first experience with dracunculoids dates back to the beginning of the sixties of the last century, when as a university student working on the parasites of reptiles in former czechoslovakia, i discovered in grass-snakes in a South-Slovakian locality a strange, at that time almost unknown nematode Dracunculus oesophageus, previously reported only in italy. later, at the institute of parasitology, Academy of Sciences of the czech Republic (previously the czechoslovak Academy of Sciences), originally in prague and

Ukázka knihy z internetového knihkupectví www.kosmas.cz 8 Preface from 1985 in České budějovice, i had a possibility to study a great number of dracunculoid species: mainly parasites of fishes, rarely those parasitizing reptiles and mammals and from different countries of the world. these materials were collected by me and my fellow-workers. Some were provided by foreign colleagues. Specimens of some species were borrowed for a re- examination from different foreign museums and other scientific institutions. Accordingly, the species descriptions in this monograph are often based on the author’s studies while others were adapted from the respective literature. in addition to descriptions and illustrations, i included for each dracunculoid and anguillicoloid species the data on its hosts, site of localization, distribution and in particular their life cycles and bionomy, provided that such data are available. my work in previous years on the life cycles of several species of Philometra and Anguillicoloides that parasitize european fishes contributed to the knowledge of these parasites in this respect. A large amount of literary data on dracunculoids and anguillicoloids has accummulated, particularly those dealing with the famous human pathogen and, more recently, , a highly pathogenic east-Asian parasite of eels (Anguilla spp.) introduced into europe and some other continents about twenty five years ago. there are also many reports on Philometra sp. in the extensive literature about fish parasites. therefore, i made no attempt to obtain every record of dracunculoids, which is nearly impossible. thus, there may be published host and locality records that are not included here. nevertheless, i believe that my lists are reasonably complete. however, when using this book for the identification of dracunculoids, it is necessary to take into account that it only summarizes the present state of knowledge about this group of nematodes, which as a whole remains insufficiently recognized. many species are still waiting for their discovery. i am grateful to prof. Vlastimil baruš from the institute of Vertebrate biology, AScR, brno for reading this book in manuscript and making critical comments and useful suggestions as to content and presentation. drs. david modrý from the faculty of Veterinary medicine in brno, Jiljí Sitko from the Regional museum in přerov and miloš Anděra from the national museum in prague helped with scientific names of host reptiles, birds and mammals, respectively. thanks are offered to irena husáková, institute of parasitology, AScR, České budějovice for technical assistance during the work. Special thanks are due to dr. hassan hashmi, university of massachusetts, for revising the english. i would like to express my thanks to all who, during years of studies on dracunculoids, provided me with the type and other specimens, thus making the present work possible: david i. Gibson, the natural history museum, london; uK, Jean-lou Justine, museum national d’histoire naturelle, paris,

U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 Preface 9 france; Ahmed tayeh, World health organization, Geneva, Switzerland; marianne Køie, marine biological laboratory, copenhagen university, helsingør, denmark; leo margolis, pacific biological Station, fisheries and oceans, nanaimo, british columbia, canada; Anna Kohn, instituto oswaldo cruz, Rio de Janeiro, brazil; Kálmán molnár and czaba Székely, Veterinary medical Research institute, hungarian Academy of Sciences, budapest, hungary; lia paggi, istituto di parassitologia, università di Roma “la Sapienza”, italy; david di cave, dipartimento Sanitá e biologia cellulare, università di Roma “tor Vergata”, Rome, italy; Kazuya nagasawa, institute of far Seas fisheries, fisheries Agency of Japan, Shimizu, Japan; Kazuo ogawa, department of Aquatic bioscience, Graduate School of Agricultural and life Sciences, university of tokyo, tokyo, Japan; pin nie, Guitang Wang, Shangong Wu and huisheng Wu, laboratory of fish diseases, institute of hydrobiology, chinese Academy of Sciences, Wuhan, china; h. hirose, nihon university, tokyo, Japan; Guillermo Salgado-maldonado, instituto de biología, universidad nacional Autónoma de méxico, mexico city, mexico; Victor Vidal-martínez and leopoldina Aguirre-macedo, centro de investigacion y de estudios Avanzados del ipn, unidad mérida, mérida, mexico; horst taraschewski, institute of zoology, university of Karlsruhe, Karlsruhe, Germany; e. Karlsbakk, institute of fisheries and marine biology, university of bergen, norway; maurice d. little and barry G. campbell, tulane medical center, tulane university, new orleans, uSA; b. Jones, fisheries Research centre, ministry of Agriculture and fisheries, Wellington, new zealand; Shigehiko urawa, hokkaido Salmon hatchery, fisheries Agency of Japan, Sapporo, Japan; d. c. lee, South Australian museum, Adelaide, Australia; Shunya Kamegai, meguro parasitological museum, tokyo, Japan; ilan paperna, department of Sciences, hebrew university of Jerusalem, Jerusalem, israel; puqin Wang, parasitology Research laboratory, fujian normal university, china; Jo G. Van As, department of zoology and entomology, university of the free State, South Africa; Gill V. Spangenberg, underwater World, San francisco, california, uSA; david G. huffman, freeman Aquatic Station, Southwest texas State university, San marcos, texas, uSA; Russel p. hobbs, division of Veterinary and biomedical Sciences, murdoch university, murdoch, Australia; Winston R. Kay, department of zoology and entomology, School of life Sciences, the university of Queensland, brisbane, Australia; Juan m. timi, departamento de biología, universidad nacional de mar del plata, Argentina, ercument Genc, department of Aquaculture and fisheries, mustafa Kemal university, hatay, turkey; Atheer h. Ali, department of fisheries and marine Resources, college of Agriculture, basrah university, basrah, iraq; clive R. Kennedy, department of zoology, university of exeter, exeter, uK; G. Arbocco, museo civico di Storia naturale, Genoa, italy; G. V. Vasilkov, ViGiS, moscow, Russia; dalisey l. Ribu, department of

U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 10 Preface microbiology and parasitology, the university of Queensland, brisbane, Australia; Ahmed hafiz, marine Research Section, ministry of fisheries, Republic of maldives; Robert Konečný, umweltbundesamt / environment Agency, Vienna, Austria; céline levron, laboratoire parasites et ecosystèmes méditerranées, université de corse, corte, france; thorsten Walter, marine pathology, Group, institut für meereskunde Kiel, Kiel, Germany; isaure du buron, college of biology, university of charlestown, South carolina, uSA; patricia pilitt and eric p. hoberg, uS national parasite collection, beltsville, maryland, uSA; predrag cakić, institute of biological Research, belgrade, yugoslavia; Vladimíra hanzelová and marta Špakulová, parasitological institute, Slovak Academy of Sciences, Košice, Slovak Republic; iva dyková, Radim ergens, ivan fiala, Roman Kuchta, Jiří lom and tomáš Scholz, institute of parasitology, Academy of Sciences of the czech Republic, České budějovice, czech Republic; milan Gelnar, Andrea Šimková and ludmila Vojtková, department of zoology and ecology, faculty of Sciences, masaryk university, brno, czech Republic; Vlastimil baruš, institute of Vertebrate biology, Academy of Sciences of the czech Republic, brno, czech Republic; and Antonín prouza and Stanislav Červinka, State Veterinary institute, České budějovice, czech Republic. for help in securing specimens and for providing me with necessary literature, i am also indebted to: Roy c. Anderson, department of zoology, university of Guelph, Guelph, ontario, canada; p. Ghittino, istituto zoopro - filactico Sperimentale del piemonte e della liguria, torino, italy; A. m. parukhin, institute of biology of Southern Seas, Academy of Sciences of the ukr. SSR, Sevastopol, ukraine (then ukr.SSSR); Robin m. overstreet, Gulf coast Research laboratory, the university of Southern mississippi, ocean Springs, mississippi, uSA; thomas l. crosby, Virginia State university, petersburg, Virginia, uSA; marcelo e. oliva, universidad de Antofegasta, Antofegasta, chile; Valentina A. tikhomirova, tver, Russia; Sergey G. Sokolov, institute of ecology and evolution, Russian Academy of Sciences, moscow, Russia; Annie J. petter, museum national d’histoire naturelle, paris, france; and Sandy cairncross and Ralph muller, department of infectious and tropical diseases, london School of hygiene and tropical medicine, london, uK. many of the illustrations in the book have been redrawn from published works. for this, i am grateful to the authors whose names, with date of publication, appear in the captions to the relevant figures. the full title and publisher of each source is cited in the reference list. i thank the following publishers for their kind permission to use illustrations in their publications: Academia (figs. 17, 122, 124, 143, 155A–e, 175A–e, G–J, 192, 199, 203, 205), Acta Hydrobiologica Sinica (fig. 86 c–e), Acta Parasitologica (figs. 110, 117, 124, 126, 130, 138, 139, 159, 163, 168, 170, 174 A–h), Acta Societatis Zoologicae Bohemicae (former Acta Societatis Zoologicae Bohemoslovacae) (figs. 50, 121,

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127), Acta Veterinaria Hungarica (figs. 118, 155 f), Acta Zoologica Mexicana (fig. 165 A–d), Acta Zoologica Sinica (fig. 209), Acta Zootaxonomica Sinica (fig. 132 A–c), American Journal of Hygiene (fig. 32 b–l), American Journal of Tropical Medicine (fig. 28 f–h), Angewandte Parasitologie (fig. 197), Annals and Magazine of Natural History (fig. 62 c), Parasite (former Annals de Parasitologie Humaine et Comparée) (figs. 16, 23 e, h–z, 33 l–n), Arquivos do Instituto Biologigo, S. Paulo (figs. 95, 182), Atas da Sociedade de Biologia do Rio de Janeiro (fig. 90 b–d, f, 196), Bulletin du Muséum National d’Histoire Naturelle [© publications Scientifiques du muséum national d’histoire naturelle, paris] (figs. 39, 71, 72, 119, 128 c–m), Bulletin of the Nansei Regional Fishery Research Laboratory (fig. 85), Bulletin de la Société Zoologique de France (fig. 22 d–f, i, J), Canadian Journal of Fisheries and Aquatic Sciences (fig. 131), Canadian Journal of Zoology (figs. 28 e, i, 29, 48, 65, 67, 74 A–c, f, G, i–l, 180 A, bd–f, h–m,), Chinese Journal of Zoology (fig. 82 d–f), J. & A. churchill, london (fig. 113 c), Ciencias Marinas (fig. 46 A, b), Comparative Parasitology (former Proceedings of the Helminthological Society of Washington) (figs. 28 A–d, 74 d, e, h, 105 c, d, G, h), Comptes Rendus des Séances (et Mémoires) de la Société de Biologie et de Ses Filiales, Paris (fig. 60 A–c), Contributions to Canadian Biology and Fisheries (fig. 65 A, b, d, e, f, h), Diseases of Aquatic Organisms [© inter-Research] (fig. 223), Experimental Pathology and Parasitology (fig. 174 i, J), Folia Parasitologica (figs. 3–6, 10–13, 21, 25, 26, 35, 37, 38, 41, 44, 46 c–J, 52–55, 63, 77, 78, 84, 91, 92, 96 b, 106–109, 115, 125, 133–137, 140, 142, 143–147, 152, 156, 164, 165 e–G, 169, 171, 183, 190, 198, 208, 210–222), Helminthologia (fig. 68), international Academic publishers (fig. 20), Japanese Journal of Zoology (figs. 49, 64 b, d, 86 A, b, 123, 141, 194 c, d), Japanese Journal of Parasitology (fig. 193 d–f), Journal of Helminthology (figs. 81, 89, 93, 94, 104 A, b, 105 A, b, e, f, 120, 153, 166, 167 d, e, 172 d–f, 177, 189), Journal of the Medical College in Keijo (fig. 82 A–c), Journal of Parasitology (figs. 14, 22 K, 30 A–f, l, 34 A, b, e, f, 45, 56–58, 75, 76, 79, 87, 88, 102, 148, 186 c, d, f, G, h, 207), Mémoires de l’Institut Scientifique du Madagascar (fig. 23 A–d, f, G), Memórias do Instituto Oswaldo Cruz (figs. 24, 51), nauka, moscow (figs. 18, 19, 111 e, 167 A–c, 175 f, 176, 206), naukova dumka, Kiev (figs. 116, 128 A, b, 129 e, f, 191 e, f), ocean press, beijing (fig. 179), Ophelia (fig. 47 c–f), Parasitology (figs. 64 A, e, f, 90 A, e), Parasitology Research (former Zeitschrift für Parasitologie) [© Springer] (figs. 27 A–d, 34 c, d, G, 42, 59, 157), Parazitologiya (figs. 70, 178, 204), Proceedings of the Academy of Natural Sciences of Philadelphia (fig. 167 f), Proceedings of the Latvian Academy of Sciences (figs. 185, 195), Publicaciones Biologicas Instituto de Investigaciones Cientificas, Monterrey (fig. 99), Research Bulletin of the Panjab University (fig. 132 d–f), Revista de Medicina Veterinaria, Buenos Aires (fig. 60 d), Revue Suisse de Zoologie (figs. 36, 40, 80), Revue de Zoologie Africaine (fig. 96 A, c–e), Rivista di Parassitologia (fig. 129 A–d),

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Science press, beijing (figs. 103, 112), Systematic Parasitology [© Springer] (figs. 43, 66, 83, 114, 160, 161, 194 A, b, e, f, 202), taylor and francis, london (fig. 62 A, d), Transactions of the American Microscopical Society (fig. 15), Transactions of Researches on Fish Diseases (China) (fig. 191 A–d), Transactions of the Royal Society of South Australia (fig. 151), Trudy Gelmintologicheskoy Laboratorii (GELAN) (figs. 185 c, h, 201), Trudy Leningradskogo Obshchestva Estestvoispytateley (fig. 69 b, c, e), Trudy Zoologicheskogo Instituta AN USSR (fig. 97 c, d), Veterinary Medical Journal (Egypt) (fig. 182), Zentralblatt für Bakteriologie (fig. 193 A–c), Zentralblatt für Parasitenkunde, Infektionskrankheiten und Hygiene (fig. 73), Zoologicheskiy Zhurnal (figs. 69 A, d, 101, 173, 187), Zeitschrift für wissenschaftliche Zoologie (fig. 111 A, b, d, G, h), Zoologia Polonica (fig. 162), Zoologische Jahrbücher (fig. 150), Zoologischer Anzeiger (figs. 47 A, b, 99, 158). this work was accomplished within the author’s grant project no. 524/03/0061 from the Grant Agency of the czech Republic. i wish to thank the editorial board of the Academy of Sciences of the czech Republic for the financial support that made the publication of this book possible. i am most grateful for the excellent editorial and production work of mr. pavel zátka from the publishing house Academia who helped in many ways, especially in working out the format of the book.

U k á z k a k n i h y z i n t e r n e t o v é h o k n i h k u p e c t v í w w w . k o s m a s . c z , U I D : K O S 1 8 2 5 3 3 introduction

nematodes of the spirurid superfamilies dracunculoidea Stiles, 1907 and Anguillicoloidea yamaguti, 1935, which are characterized by certain morphological features and some biological peculiarities, represent a large and diverse group of parasites with worldwide distribution. members are noted for the presence of a simple oval or triangular mouth surrounded by a variable number of cephalic papillae usually arranged in two circles. the buccal capsule, if present, is usually reduced. the oesophagus is largely divided into muscular and glandular parts but may be entirely muscular. two spicules or a sclerotized copulatory plate may be present or absent. All dracunculoids are viviparous, whereas anguillicoloids are oviparous. After fertilisation, dracunculoid females grow markedly as first-stage larvae fill their uteri. in some groups, the vulva and anus atrophy in fully gravid females and larvae are dispersed into the environment by bursting as they come in contact with water, whereas in others their larvae are released into tissues. many dracunculoids exhibit marked sexual dimorphism, in which females are highly modified and considerably larger than males. the body size of gravid females in different species ranges between 1 mm in Lucionema balatonense from european pikeperch to more than 1 m in Philometra sp. from wreckfish (moravec 2004b) or Avioserpens mosgovoyi from aquatic birds. According to moravec (2004b), the superfamily dracunculoidea includes the following nine families: dracunculidae Stiles, 1907, micropleuridae baylis et daubney, 1926, philometridae baylis et daubney, 1926, Anguillicolidae yamaguti, 1935, tetanonematidae Skryabin et Shikhobalova, 1948, Skrja - billanidae Shigin et Shigina, 1958, Guyanemidae petter, 1974, daniconema - tidae moravec et Køie, 1987, and lucionematidae moravec, molnár et Székely, 1998. the monotypic dracunculoid genus Lockenloia Adamson et caira, 1991 with L. sanguinis Adamson et caira, 1991 from sharks has not been assigned to any family and is considered incertae sedis. however, in this book, the family Anguillicolidae is removed from dracunculoidea and is placed in a separate superfamily, Anguillicoloidea (see preface). the hosts of the numerous species of these two nematode superfamilies are members of all main classes of vertebrates (fishes, amphibians, reptiles,

Ukázka knihy z internetového knihkupectví www.kosmas.cz 14 introduction birds, mammals), including man. however, their highest species and morpho - logical diversity occurs in fishes. Some species parasitize a wide range of hosts while others exhibit a relatively narrow host specificity. the dracunculoids are mostly parasites of various tissues and organ cavities and different species attack, for example, the skin and subcutaneous tissue, body musculature, eyes, orbits, gills and the swimbladder (in fish), kidneys, gonads and the circulatory system, or are found in the body cavity of the host (ivashkin et al. 1971; chabaud 1975; moravec 2004b). the dracunculoid and anguillicoloid life cycles involve aquatic crustaceans (copepods, ostracods or branchiurids) as intermediate hosts and, consequently, the transmission and the occurrence of these parasites in vertebrate definitive hosts is always associated with the aquatic environment. therefore, it is not surprising that the absolute majority of dracunculoids and all anguillicoloids are found in fishes, both freshwater and marine. of the nine dracunculoid and anguillicoloid families, eight (89%) include the forms from fishes, whereas the family dracunculidae contains a few species parasitic to birds (species of Avioserpens) and reptiles and mammals (members of Dracunculus). the micropleuridae contains four species of Micropleura from reptiles, two species of the monotypic genera Kamegainema and Protenema from amphibians, two species of each Granulinema and Phlyctainophora from elasmobranchs (sharks) and four species of Philonema from teleostean fishes. of a total number of 37 valid genera of dracunculoid and anguillicoloid nematodes with 165 recognized species, 32 genera (86%) with 145 species (88%) are found in fishes. dracunculoid nematodes are widely distributed among vertebrates, particularly in freshwater, brackish-water and marine fishes, whereas anguilli - colloids adapted only to freshwater eels (Anguilla spp.). About 450 fish species, belonging to 131 fish families and 31 orders, have been reported as the hosts of these parasites. besides the well known human parasite Dracunculus medinensis, many other dracunculoids are known as pathogens in animals such as caudate amphibians, turtles, snakes, crocodiles, birds and some mammals. Some fish dracunculoids and anguillicoloids are highly pathogenic, which are known to be agents of serious diseases of fish with economic importance, causing sometimes mass mortalities in stocks of both free-living and cultured fish (e.g., anguillicolosis of eels, philometroidosis of carps, philonemosis of salmonids). the frequent destruction of gonads caused by Philometra spp. in cultured marine perciform fishes may considerably decrease the reproduction of these fishes and may even cause full parasitic castration (Ramachandran 1975; Sakaguchi et al. 1987; moravec, ogawa et al. 2002; moravec, Glamuzina et al. 2003). fish philometrids (Philometra sp. and Philometroides sp.) were also recorded as facultative human parasites (deardorff et al. 1986; Kuroda et al. 1991).

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