DOCSLIB.ORG

UNIVERSITY of CALIFORNIA SANTA CRUZ Life In

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
UNIVERSITY of CALIFORNIA SANTA CRUZ Life In UNIVERSITY OF CALIFORNIA SANTA CRUZ Life in a patchy world: species-habitat relationships link macroalgal communities to higher trophic levels in temperate rocky reefs A dissertation submitted in partial satisfaction of the requirements for the degree of DOCTOR OF PHILOSOPHY in ECOLOGY AND EVOLUTIONARY BIOLOGY by Brenna Mahoney September 2014 The Dissertation of Brenna Mahoney is approved: _____________________________ Professor Pete Raimondi, Chair _____________________________ Professor Mark Carr _____________________________ Professor Michael Graham _____________________________ Tyrus Miller Vice Provost and Dean of Graduate Studies Copyright © by Brenna Mahoney 2014 Table of Contents List of Tables ........................................................................................................................ v List of Figures ..................................................................................................................... vi Abstract .............................................................................................................................. viii Acknowledgements ........................................................................................................... xii Introduction ......................................................................................................................... 1 1. Chapter 1 - Algal assemblage structure drives spatial variability in associated invertebrates along a wave exposure and swell disturbance gradient ...................... 4 1.1 Abstract ..................................................................................................................................... 4 1.2. Introduction ........................................................................................................................... 5 1.3 Methods .................................................................................................................................. 11 1.3.1 Study system and organisms ....................................................................................................... 11 1.3.2 Site characterization ...................................................................................................................... 12 1.3.3 Spatial and temporal patterns of algal assemblage ................................................................ 13 1.3.4 Spatial and temporal patterns of associated invertebrate assemblage ............................. 13 1.3.5 Linking algal and invertebrate assemblages ............................................................................ 14 1.4 Results .................................................................................................................................... 17 1.4.1 Site characterization ...................................................................................................................... 17 1.4.2 Spatial and temporal patterns of algal assemblage .................................................... 17 1.4.3 Spatial and temporal patterns of associated invertebrate assemblage ............................. 18 1.4.4. Linking algal and invertebrate assemblages ........................................................................... 18 1.5 Discussion ............................................................................................................................. 19 1.6 Tables ..................................................................................................................................... 25 1.7 Figures .................................................................................................................................... 30 2. Chapter 2 – Contribution of fish predation to differences in prey assemblage as a function of host algal species ....................................................................................... 32 2.1. Abstract ................................................................................................................................. 32 2.2. Introduction ......................................................................................................................... 33 2.3. Methods ................................................................................................................................ 36 2.3.1. Study site ............................................................................................................................ 36 2.3.2. Fish diet composition ..................................................................................................... 36 2.3.3. Diet items associated with different algal species ................................................................ 37 2.3.4. Prey response in absence of predation ................................................................................... 38 2.4. Results ................................................................................................................................... 41 2.4.1. Fish diet composition .................................................................................................................. 41 2.4.2. Diet items associated with different algal species ................................................................ 41 2.4.3. Prey response in absence of predation ................................................................................... 42 2.5. Discussion ............................................................................................................................ 42 iii 2.6. Tables .................................................................................................................................... 47 2.7. Figures .................................................................................................................................. 48 3. Chapter 3 – Prey availability and feeding mechanics determine ontogeny of habitat selection of a microcarnivorous fish (Oxylebius pictus) .............................. 52 3.1. Abstract ................................................................................................................................. 52 3.2. Introduction ......................................................................................................................... 53 3.3. Methods ................................................................................................................................ 56 3.3.1. Study Site ........................................................................................................................................ 56 3.3.2. Size of prey available in the environment .............................................................................. 57 3.3.3. Ontogenetic differences in diet and prey selectivity of Oxylebius pictus .......................... 57 3.3.4. Ontogenetic changes in jaw morphology of Oxylebius pictus ................................ 59 3.3.5. Algal associations of Oxylebius pictus ......................................................................................... 60 3.4. Results ................................................................................................................................... 61 3.4.1. Size of prey available in environment ..................................................................................... 61 3.4.2. Ontogenetic differences in diet and prey selectivity of Oxylebius pictus .......................... 62 3.4.3. Ontogenetic changes in jaw morphology of Oxylebius pictus ............................................. 64 3.4.5. Algal associations of Oxylebius pictus ......................................................................................... 64 3.5. Discussion ............................................................................................................................ 65 3.6. Figures .................................................................................................................................. 71 Discussion .......................................................................................................................... 78 Bibliography ....................................................................................................................... 82 iv List of Tables Table 1-1. Dissimilarity of percentage results determined by SIMPER analysis showing algal species that contribute most to average dissimilarity (cut-off percentage: 90%) between algal assemblages at each site surveyed. Average dissimilarity values between sites are in bold. ...................................................................................... 25 Table 1-2. Mean abundance of invertebrate groups collected from six algal species and standardized to algal dry weight (#invertebrate/g algal replicate). Total and percent abundance of invertebrate groups reported. .......................................................... 26 Table 1-3. Results of PERMANOVA testing differences of invertebrate assemblage composition as a function of site and sample month. Significant differences (p<0.05) between sites are indicated in bold. ......................................................... 27 Table 1-4. Results of PERMANOVA testing differences in invertebrate assemblage composition as a function of algal species and site. ............................................... 28 Table 1-5. Correlation coefficient results from the BIOENV procedure for the top ten models of algal species explaining the invertebrate
Load more

Recommended publications
  • Title CYCLOPOID COPEPODS of the FAMILY
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Kyoto University Research Information Repository CYCLOPOID COPEPODS OF THE FAMILY Title CHONDRACANTHIDAE PARASITIC ON NEW ZEALAND MARINE FISHES Author(s) Ho, Ju-Shey PUBLICATIONS OF THE SETO MARINE BIOLOGICAL Citation LABORATORY (1975), 22(5): 303-319 Issue Date 1975-11-29 URL http://hdl.handle.net/2433/175898 Right Type Departmental Bulletin Paper Textversion publisher Kyoto University CYCLOPOID COPEPODS OF THE FAMILY CHONDRACANTHIDAE PARASITIC ON NEW ZEALAND MARINE FISHES Ju-SHEY HO Department of Biology, California State University, Long Beach, California 90840 U.S.A. With Text-figures 1-10 Chondracanthidae is a family of highly transformed cyclopoid copepods that are found exclusively on marine demersal fish. Although a complete life history of this family of copepods is still unknown, it seems, judging from the available infor­ mation of their larval development, that the parasites do not require an intermediate host. Both adult and larva are found in the oral-branchial cavity of the fish, attaching to the host tissue by their powerful, hook-like second antenna. Although a few species are known to live in the nasal cavity, they have not been found on the body surface or fins of the fish. The male is characteristically dwarf and attaches to the genital area of the female throughout its life. In many species, the transformed female has a pair of small processes on the posteroventral surface of the trunk just in front of the genital segment. The pigmy male holds on to one of these two processes by its transformed hook-like second antennae.
    [Show full text]
  • ACTA ICHTHYOLOGICA ET PISCATORIA Jadwiga GRABDA
    ACTA ICHTHYOLOGICA ET PISCATORIA Vol. V, Faac. 1 Szczecin, 197 5 Jadwiga GRABDA,lhrahimAbdel Fattah Mahmoud SOLIMAN Parultolcgy COPEPODS - PARASITES OF THE GENUS MERLUCCIUS FROM THE ATLANTIC OCEAN AND MEDITERRANEAN SEA PASOZYTNICZE WIDl:.ONOGI RYB RODZAJU MERLUCCIUS Z OCEANU ATLANTYCKIEGO I MORZA SRODZIEMNEGO Institute of Ichthyology 3 species of parasitic copepods were found on Atlantic hakes caught off the western coasts of Europe, Africa, the Medi­ terranean Sea (off Alexandria), and North America. The species are: Chondracanthus fnerluccii, Brachiel/a merluccii and Parabrachiella australis. The parasites importance as indicators of the affinities between hakes is discussed. Various hypotheses concerning the origin of the genus Merluccius are presented. INTRODUCTION Studies on parasites as biological indicators of their host's population status, affinities, migrations, origin and zoogeographic distribution are a valuable method to explain many problems of biology of fish. The parasitic species of a narrow specificity are particularly interesting as indicators. The parasitic copepods of the genera Chondracanthus, Brachiella and Parabrachiellaappear to play such a role in hake. During the investigations on species variability within the genus Merluccius from the Atlantic and Mediterranean Sea (Soliman, 1973), the parasitic copepods were collected in order to utilize them as possible indicators of specific affiliations and affinities between the hakes investigated. MATERIALS AND METHOD The parasites were collected in 1971 � 1973 from mouth and gill cavities of the fishes exami1ied. 32 Jadwiga Grabda, Ibrahim Abdel Fattah Mahmoud Soliman Table 1 and the chart enclosed (Fig. 1) summarize number of fishesexamined, fishing grounds and catching time of particular hake stocks. 45' "1' tJt�H m-����;-��������-f-������������-"<t--==,__���11,' o' ,s· 45' Fig.
    [Show full text]
  • Have Chondracanthid Copepods Co-Speciated with Their Teleost Hosts?
    Systematic Parasitology 44: 79–85, 1999. 79 © 1999 Kluwer Academic Publishers. Printed in the Netherlands. Have chondracanthid copepods co-speciated with their teleost hosts? Adrian M. Paterson1 & Robert Poulin2 1Ecology and Entomology Group, Lincoln University, PO Box 84, Lincoln, New Zealand 2Department of Zoology, University of Otago, PO Box 56, Dunedin, New Zealand Accepted for publication 26th October, 1998 Abstract Chondracanthid copepods parasitise many teleost species and have a mobile larval stage. It has been suggested that copepod parasites, with free-living infective stages that infect hosts by attaching to their external surfaces, will have co-evolved with their hosts. We examined copepods from the genus Chondracanthus and their teleost hosts for evidence of a close co-evolutionary association by comparing host and parasite phylogenies using TreeMap analysis. In general, significant co-speciation was observed and instances of host switching were rare. The preva- lence of intra-host speciation events was high relative to other such studies and may relate to the large geographical distances over which hosts are spread. Introduction known from the Pacific, and 17 species from the Atlantic (2 species occur in both oceans; none are About one-third of known copepod species are par- reported from the Indian Ocean). asitic on invertebrates or fish (Humes, 1994). The Parasites with direct life-cycles, as well as para- general biology of copepods parasitic on fish is much sites with free-living infective stages that infect hosts better known than that of copepods parasitic on in- by attaching to their external surfaces, are often said to vertebrates (Kabata, 1981).
    [Show full text]
  • Orden POECILOSTOMATOIDA Manual
    Revista IDE@ - SEA, nº 97 (30-06-2015): 1-15. ISSN 2386-7183 1 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ Clase: Maxillopoda: Copepoda Orden POECILOSTOMATOIDA Manual CLASE MAXILLOPODA: SUBCLASE COPEPODA: Orden Poecilostomatoida Antonio Melic Sociedad Entomológica Aragonesa (SEA). Avda. Francisca Millán Serrano, 37; 50012 Zaragoza [email protected] 1. Breve definición del grupo y principales caracteres diagnósticos El orden Poecilostomatoida Thorell, 1859 tiene una posición sistemática discutida. Tradicionalmente ha sido considerado un orden independiente, dentro de los 10 que conforman la subclase Copepoda; no obstante, algunos autores consideran que no existen diferencias suficientes respeto al orden Cyclopoida, del que vendrían a ser un suborden (Stock, 1986 o Boxshall & Halsey, 2004, entre otros). No obstante, en el presente volumen se ha considerado un orden independiente y válido. Antes de entrar en las singularidades del orden es preciso tratar sucintamente la morfología, ecolo- gía y biología de Copepoda, lo que se realiza en los párrafos siguientes. 1.1. Introducción a Copepoda Los copépodos se encuentran entre los animales más abundantes en número de individuos del planeta. El plancton marino puede alcanzar proporciones de un 90 por ciento de copépodos respecto a la fauna total presente. Precisamente por su número y a pesar de su modesto tamaño (forman parte de la micro y meiofauna) los copépodos representan una papel fundamental en el funcionamiento de los ecosistemas marinos. En su mayor parte son especies herbívoras –u omnívoras– y por lo tanto transformadoras de fito- plancton en proteína animal que, a su vez, sirve de alimento a todo un ejército de especies animales, inclu- yendo gran número de larvas de peces.
    [Show full text]
  • Observing Copepods Through a Genomic Lens James E Bron1*, Dagmar Frisch2, Erica Goetze3, Stewart C Johnson4, Carol Eunmi Lee5 and Grace a Wyngaard6
    Bron et al. Frontiers in Zoology 2011, 8:22 http://www.frontiersinzoology.com/content/8/1/22 DEBATE Open Access Observing copepods through a genomic lens James E Bron1*, Dagmar Frisch2, Erica Goetze3, Stewart C Johnson4, Carol Eunmi Lee5 and Grace A Wyngaard6 Abstract Background: Copepods outnumber every other multicellular animal group. They are critical components of the world’s freshwater and marine ecosystems, sensitive indicators of local and global climate change, key ecosystem service providers, parasites and predators of economically important aquatic animals and potential vectors of waterborne disease. Copepods sustain the world fisheries that nourish and support human populations. Although genomic tools have transformed many areas of biological and biomedical research, their power to elucidate aspects of the biology, behavior and ecology of copepods has only recently begun to be exploited. Discussion: The extraordinary biological and ecological diversity of the subclass Copepoda provides both unique advantages for addressing key problems in aquatic systems and formidable challenges for developing a focused genomics strategy. This article provides an overview of genomic studies of copepods and discusses strategies for using genomics tools to address key questions at levels extending from individuals to ecosystems. Genomics can, for instance, help to decipher patterns of genome evolution such as those that occur during transitions from free living to symbiotic and parasitic lifestyles and can assist in the identification of genetic mechanisms and accompanying physiological changes associated with adaptation to new or physiologically challenging environments. The adaptive significance of the diversity in genome size and unique mechanisms of genome reorganization during development could similarly be explored.
    [Show full text]
  • DEEPFISHMAN Document 5 : Review of Parasites, Pathogens
    DEEPFISHMAN Management And Monitoring Of Deep-sea Fisheries And Stocks Project number: 227390 Small or medium scale focused research action Topic: FP7-KBBE-2008-1-4-02 (Deepsea fisheries management) DEEPFISHMAN Document 5 Title: Review of parasites, pathogens and contaminants of deep sea fish with a focus on their role in population health and structure Due date: none Actual submission date: 10 June 2010 Start date of the project: April 1st, 2009 Duration : 36 months Organization Name of lead coordinator: Ifremer Dissemination Level: PU (Public) Date: 10 June 2010 Review of parasites, pathogens and contaminants of deep sea fish with a focus on their role in population health and structure. Matt Longshaw & Stephen Feist Cefas Weymouth Laboratory Barrack Road, The Nothe, Weymouth, Dorset DT4 8UB 1. Introduction This review provides a summary of the parasites, pathogens and contaminant related impacts on deep sea fish normally found at depths greater than about 200m There is a clear focus on worldwide commercial species but has an emphasis on records and reports from the north east Atlantic. In particular, the focus of species following discussion were as follows: deep-water squalid sharks (e.g. Centrophorus squamosus and Centroscymnus coelolepis), black scabbardfish (Aphanopus carbo) (except in ICES area IX – fielded by Portuguese), roundnose grenadier (Coryphaenoides rupestris), orange roughy (Hoplostethus atlanticus), blue ling (Molva dypterygia), torsk (Brosme brosme), greater silver smelt (Argentina silus), Greenland halibut (Reinhardtius hippoglossoides), deep-sea redfish (Sebastes mentella), alfonsino (Beryx spp.), red blackspot seabream (Pagellus bogaraveo). However, it should be noted that in some cases no disease or contaminant data exists for these species.
    [Show full text]
  • And Endoparasite Communities of Wild Mediterranean Teleosts by a Metabarcoding Approach
    RESEARCH ARTICLE Characterization of ecto- and endoparasite communities of wild Mediterranean teleosts by a metabarcoding approach 1 1 1 Mathilde ScheiflerID *, Magdalena Ruiz-RodrõÂguez , Sophie Sanchez-Brosseau , 1 2 3 4 Elodie Magnanou , Marcelino T. SuzukiID , Nyree West , SeÂbastien Duperron , Yves Desdevises1 1 Sorbonne UniversiteÂ, CNRS, Biologie InteÂgrative des Organismes Marins, BIOM, Observatoire OceÂanologique, Banyuls/Mer, France, 2 Sorbonne UniversiteÂ, CNRS, Laboratoire de Biodiversite et Biotechnologies Microbiennes, LBBM Observatoire OceÂanologique, Banyuls/Mer, France, 3 Sorbonne a1111111111 UniversiteÂ, CNRS, Observatoire OceÂanologique de Banyuls, Banyuls/Mer, France, 4 CNRS, MuseÂum a1111111111 National d'Histoire Naturelle, MoleÂcules de Communication et Adaptation des Micro-organismes, UMR7245 a1111111111 MCAM, MuseÂum National d'Histoire Naturelle, Paris, France a1111111111 a1111111111 * [email protected] Abstract OPEN ACCESS Next-generation sequencing methods are increasingly used to identify eukaryotic, unicellu- Citation: Scheifler M, Ruiz-RodrõÂguez M, Sanchez- lar and multicellular symbiont communities within hosts. In this study, we analyzed the non- Brosseau S, Magnanou E, Suzuki MT, West N, et specific reads obtained during a metabarcoding survey of the bacterial communities associ- al. (2019) Characterization of ecto- and ated to three different tissues collected from 13 wild Mediterranean teleost fish species. In endoparasite communities of wild Mediterranean teleosts by a metabarcoding approach. PLoS ONE total, 30 eukaryotic genera were identified as putative parasites of teleosts, associated to 14(9): e0221475. https://doi.org/10.1371/journal. skin mucus, gills mucus and intestine: 2 ascomycetes, 4 arthropods, 2 cnidarians, 7 nema- pone.0221475 todes, 10 platyhelminthes, 4 apicomplexans, 1 ciliate as well as one order in dinoflagellates Editor: Anne Mireille Regine Duplouy, Lund (Syndiniales).
    [Show full text]
  • Guide to the Parasites of Fishes of Canada Part II - Crustacea
    Canadian Special Publication of Fisheries and Aquatic Sciences 101 DFO - Library MPO - Bibliothèque III 11 1 1111 1 1111111 II 1 2038995 Guide to the Parasites of Fishes of Canada Part II - Crustacea Edited by L. Margolis and Z. Kabata L. C.3 il) Fisheries Pêches and Oceans et Océans Caned. Lee: GUIDE TO THE PARASITES OF FISHES OF CANADA PART II - CRUSTACEA Published by Publié par Fisheries Pêches 1+1 and Oceans et Océans Communications Direction générale Directorate des communications Ottawa K1 A 0E6 © Minister of Supply and Services Canada 1988 Available from authorized bookstore agents, other bookstores or you may send your prepaid order to the Canadian Government Publishing Centre Supply and Services Canada, Ottawa, Ont. K1A 0S9. Make cheques or money orders payable in Canadian funds to the Receiver General for Canada. A deposit copy of this publication is also available for reference in public libraries across Canada. Canada : $11.95 Cat. No. Fs 41-31/101E Other countries: $14.35 ISBN 0-660-12794-6 + shipping & handling ISSN 0706-6481 DFO/4029 Price subject to change without notice All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of the Publishing Services, Canadian Government Publishing Centre, Ottawa, Canada K1A 0S9. A/Director: John Camp Editorial and Publishing Services: Gerald J. Neville Printer: The Runge Press Limited Cover Design : Diane Dufour Correct citations for this publication: KABATA, Z. 1988. Copepoda and Branchiura, p. 3-127.
    [Show full text]
  • Title Studies on the Phylogenetic Implications of Ontogenetic
    Studies on the Phylogenetic Implications of Ontogenetic Title Features in the Poecilostome Nauplii (Copepoda : Cyclopoida) Author(s) Izawa, Kunihiko PUBLICATIONS OF THE SETO MARINE BIOLOGICAL Citation LABORATORY (1987), 32(4-6): 151-217 Issue Date 1987-12-26 URL http://hdl.handle.net/2433/176145 Right Type Departmental Bulletin Paper Textversion publisher Kyoto University Studies on the Phylogenetic Implications of Ontogenetic Features in the Poecilostome Nauplii (Copepoda: Cyclopoida) By Kunihiko Izawa Faculty ofBioresources, Mie University, Tsu, Mie 514, Japan With Text-figures 1-17 and Tables 1-3 Introduction The Copepoda includes a number of species that are parasitic or semi-parasitic onjin various aquatic animals (see Wilson, 1932). They live in association with par­ ticular hosts and exhibit various reductive tendencies (Gotto, 1979; Kabata, 1979). The reductive tendencies often appear as simplification and/or reduction of adult appendages, which have been considered as important key characters in their tax­ onomy and phylogeny (notably Wilson, op. cit.; Kabata, op. cit.). Larval morpholo­ gy has not been taken into taxonomic and phylogenetic consideration. This is par­ ticularly unfortunate when dealing with the poecilostome Cyclopoida, which include many species with transformed adults. Our knowledge on the ontogeny of the Copepoda have been accumulated through the efforts of many workers (see refer­ ences), but still it covers only a small part of the Copepoda. History of study on the nauplii of parasitic copepods goes back to the 1830's, as seen in the description of a nauplius of Lernaea (see Nordmann, 1832). I have been studying the ontogeny of the parasitic and semi-parasitic Copepoda since 1969 and have reported larval stages of various species (Izawa, 1969; 1973; 1975; 1986a, b).
    [Show full text]
  • Does Male Chondracanthus Lophii (Crustacea: Copepoda) Feed?
    J. Mar. Biol. Ass. U.K. (2004), 84,711^716 Printed in the United Kingdom Does male Chondracanthus lophii (Crustacea: Copepoda) feed? Pia Òstergaard Department of Zoology,The Natural History Museum, Cromwell Road, London, SW7 5BD, UK and Department of Biological Sciences, Imperial College London, Silwood Park Campus, Ascot, SL5 7PY, UK. E-mail: [email protected] Male Chondracanthus lophii was studied using light and electron microscopy. Observations on external morphology and internal anatomy are presented. Males possess a full set of functional mouth parts, the digestive system is active and the dominant cell type in the midgut is identi¢ed as the vacuolar type B-cell, but the gut is a blind ending sac with no anus. The gut contents were a homogenous, amorphous mass. The combination of active feeding and digestion with a blind ending gut supports the inference that males feed on special secretions produced by glands in the nuptial organs of the female. It is speculated that depen- dence on such secretion reduces or eliminates the production of faecal matter. Observations on the reproductive system con¢rmed the typical chondracanthid pattern. INTRODUCTION 01826’E). Females with males attached were removed from the host by hand. The material was deposited in The Chondracanthus Delaroche, the type genus of the family Natural History Museum, London (BMNH 2002.191 Chondracanthidae Milne-Edwards, currently has 38 ^ 203). valid species (Ho, 1991; Òstergaard, 2003) including Chondracanthus lophii Johnston. This species has been de- scribed several times under a variety of di¡erent names Light microscopy (LM) (see Kabata, 1979 for synonymy) but its biology is poorly Two ovigerous females, each with one male, were known.
    [Show full text]
  • Fishery Bulletin/U S Dept of Commerce National Oceanic
    LENGTH-WEIGHT RELATIONSHIP, FOOD HABITS, PARASITES, AND SEX AND AGE DETERMINATION OF THE RATFISH, HYDROLAGUS COLLIEI (LAY AND BENNETT)' ALLYN G. JOHNSON' AND HOWARD F. HORTON' ABSTRAcr In the fall and winter of 1965-1967, 292 ratfish (Hydrolagus colliei) Wi!re collected from four locations off the Pacific coast of Oregon. Specimens were examined for length-weight relationships, food habits, parasites, and a method of sex and age determination. Equa­ tions describing the body weight-body length (snout to vent) relationships were log weight = log -4.3217 + 3.0546 log length for males, and log weight = log -4.1692 + 2.9720 log length for females. The food organisms most important to ratfish were shrimp (Pandalus and Crago), mollusks (Musculus and Amphissa), and echinoderms (Bri­ saster). Two occurrences of cannibalism were found in ratfish collected off Cape Arago, Oreg. Infestations by Gyrocotyle ranged from 29 to 66% among samples from the four locations. The copepod, Acanthochondria sp., was attached to the claspers of seven males from Cape Arago. EYi!-lens weights (wet and dry), vertebral radii, basal sections of the dorsal spine and left pectoral fin, and body-length frequencies were studied, but no accurate method of age determination was found. Tritors on the posterior side of the vomerine dental plate may be indicative of age, but the precise relationship was not determined. 'I'he ratfish, Hydrolagus colliei (Lay and Ben­ sus stenolepis (Thompson, 1915) . Conversely, nett), is a member of the class Chondrichthyes, ratfish are commonly caught in the trawls of order Chamaeriformes, and family Chimaeridae commercial fishermen who consider them a nui­ (Bailey, 1970).
    [Show full text]
  • Copepoda, Poecilostomatoida, Chondracanthidae), Parasitic on Tetraodontiform Fishes
    RESURRECTION OF ACANTHOCANTHOPSIS HEEGAARD, 1945 (COPEPODA, POECILOSTOMATOIDA, CHONDRACANTHIDAE), PARASITIC ON TETRAODONTIFORM FISHES BY DANNY TANG1,3) and JU-SHEY HO2,4) 1) School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia 2) Department of Biological Sciences, California State University, Long Beach, California 90840-3702, U.S.A. ABSTRACT The genus Acanthocanthopsis Heegaard, 1945 is considered valid based on examination of newly collected specimens of the type-species, A. quadrata Heegaard, 1945, from 2 tetraodontiform hosts (Pisces) captured in Australian waters. Pseudochondracanthus chilomycteri (Thomson, 1889) is transferred to Acanthocanthopsis. This latter genus can be differentiated from other chondracanthid genera by a combination of characters that include processes on the cephalosome, one pair of modified legs, a trunk bearing processes, a caudal ramus tipped with a small spine, a mandible armed with over 100 teeth on both margins, and a maxilliped claw with an accessory tooth in the female, as well as a vestigial first leg in the male. An amended diagnosis of Acanthocanthopsis is also provided. RÉSUMÉ Le genre Acanthocanthopsis Heegaard, 1945 est considéré comme valide après l’examen de spécimens de l’espèce-type, A. quadrata Heegaard, 1945, nouvellement prélevés sur deux hôtes Tétraodontiformes (Poissons) capturés dans les eaux australiennes. Pseudochondracanthus chilomycteri (Thomson, 1889) est transféré dans le genre Acanthocanthopsis. Ce dernier peut être différencié des autres genres de Chondracanthidae par une combinaison de caractères incluant des processus sur le céphalosome, une paire de pattes modifiées, un tronc portant des processus, une rame caudale terminée par une petite épine, une mandibule armée de plus de 100 dents sur les deux bords, et le croc du maxillipède portant une dent accessoire chez la femelle, ainsi qu’une première patte vestigiale chez le mâle.
    [Show full text]