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Fish parasites are an important part of aquatic biodiversity and knowing these species and their interactions with their hosts helps in monitoring the aquatic biota. The present study investigated the ectoparasite crustacean fauna of ten fish species from the upper Araguari River, in the state of Amapá, northern Brazil. A total of 508 fish were collected and analyzed from July to November 2014, of which 82.6% (109) were parasitized by one or more crustacean ectoparasite species. In the ten host fish species, a total of 308 ectoparasite specimens were collected, from 12 taxa, such as Argulus multicolor Stekhoven, 1937, Argulus spinulosus Silva, 1980, Argulus sp.1, Argulus sp.2, Argulus sp.3, Dipteropeltis sp., Dipteropeltis hirundo Calman, 1912, Dolops bidentata Bouvier, 1899, Dolops striata Bouvier, 1899 (Argulidae), Braga fluviatilis Richardson, 1911, Braga amapaensis Thatcher, 1996 (Cymothoidae) and Excorallana berbicensis Boone, 1918 (Corallanidae). Higher levels of prevalence and abundance were recorded for Hoplias aimara (Valenciennes, 1847) and Tometes trilobatus Valenciennes, 1850, respectively. These ectoparasites were found in the fins, integument, mouth, and anus of the host fish. Argulus sp.2 and D. bidentata were the most abundant parasites (65.1%), and had the highest species richness. This study registered 36 novel host-parasite interactions, and thus represents a new record for all host species here examined.

Infective nymphal stages of the family Sebekidae Sambon, 1922 are reported from four species of fish in Australian waters for the first time. Infected fish were collected from locations in Western Australia, the Northern Territory and north Queensland. The infective nymphs of Alofia merki Giglioli in Sambon, 1922 and Sebekia purdieae Riley, Spratt et Winch, 1990 are reported and described for the first time. The remaining specimens were identified as belonging to the genus Sebekia Sambon, 1922 based on the combination of buccal cadre shape, shape and size of hooks, and overall body size, but could not be attributed to any of the other species of Sebekia already reported due to missing required morphological features. DNA sequences of members of the family Sebekidae are presented for the first time. The lack of knowledge on the pentastome fauna of wild crocodiles, and any potential intermediate hosts, in northern Australia, is also outlined.

The aims of this study were to produce a checklist of the metazoan parasites of fishes from the Celestun coastal lagoon and to determine the degree of faunal similarity among the fishes based on the metazoan parasites they share. A checklist was prepared including all available records (1996-2014) of parasites of marine, brackish water and freshwater fishes of the area. All of these data were included in a presence/absence database and used to determine similarity via Jaccard's index. The results indicate the presence of 62 metazoan parasite species infecting 22 fish species. The number of metazoan parasite species found in the fishes from the Celestún lagoon is apparently the highest reported worldwide for a tropical coastal lagoon. The parasites included 12 species of adult digeneans, 27 digeneans in the metacercarial stage, 6 monogeneans, 3 metacestodes, 9 nematodes, 2 acanthocephalans, 2 crustaceans and 1 annelid. Forty parasite species were autogenic and 23 were allogenic and 1 unknown. The overall similarity among all of the species of fish with respect to the metazoan parasites they share was low (0.08 ± 0.12), with few similarity values above 0.4 being obtained. This low similarity was due primarily to the presence of suites of parasites exclusive to specific species of fish. The autogenic component of the parasite fauna (40 species) dominated the allogenic component (21 species). The most likely explanation for the large number of fish parasites found at Celestún is the good environmental condition of the lagoon, which allows the completion of parasite life cycles and free circulation of euryhaline fishes from the marine environment bringing marine parasites into the lagoon.

The use of intertidal sandy beaches by fish and macrocrustaceans was studied at different temporal scales at the mouth of a tropical estuary. Samples were taken along the lunar and diel cycles in the late dry and rainy seasons. Fish assemblage (number of species, density and biomass), crustaceans and wrack biomass, showed significant interactions among all studied factors, and the combination of moon phase and diel cycle, resulting in different patterns of environmental variables (depth, water temperature and dissolved oxygen), affected habitat use by the different species. Variances in faunal community were detected between seasons, stimulated by salinity fluctuations from freshwater input during the rainy season. These differences suggest an important cycling of habitats and an increase in connectivity between adjacent habitats (estuary and coastal waters). Moreover, the results showed that this intertidal sandy beach also provides an alternative nursery and protected shallow-water area for the initial development phase of many marine and estuarine species. In addition, this intertidal habitat plays an important role in the maintenance of the ecological functioning of the estuarine-coastal ecosystem continuum., (© 2014 The Fisheries Society of the British Isless.)

Not only seasonality but also taxonomic resolution of prey categories has been shown to affect diet studies. We analyzed the stomach contents of three sympatric species, Stellifer rastrifer, S. brasiliensis and S. stellifer, sampled monthly from August 2003 to October 2004 in Caraguatatuba Bay, southeastern Brazil. General characteristics and similarities among their diets were evaluated by considering high taxonomic ranks of all prey groups, and also the lower taxonomic ranks of the main prey groups. Dietary similarity was relatively high among species and low between seasons, and both evaluation criteria gave the equivalent results. The rare items, however, provided information about resource partition, and the species compositions of the most important groups were apparently good indicators of food availability.

Background: In the Mexican Caribbean, the exotic lionfish Pterois volitans has become a species of great concern because of their predatory habits and rapid expansion onto the Mesoamerican coral reef, the second largest continuous reef system in the world. This is the first report of DNA identification of stomach contents of lionfish using the barcode of life reference database (BOLD)., Methodology/principal Findings: We confirm with barcoding that only Pterois volitans is apparently present in the Mexican Caribbean. We analyzed the stomach contents of 157 specimens of P. volitans from various locations in the region. Based on DNA matches in the Barcode of Life Database (BOLD) and GenBank, we identified fishes from five orders, 14 families, 22 genera and 34 species in the stomach contents. The families with the most species represented were Gobiidae and Apogonidae. Some prey taxa are commercially important species. Seven species were new records for the Mexican Caribbean: Apogon mosavi, Coryphopterus venezuelae, C. thrix, C. tortugae, Lythrypnus minimus, Starksia langi and S. ocellata. DNA matches, as well as the presence of intact lionfish in the stomach contents, indicate some degree of cannibalism, a behavior confirmed in this species by the first time. We obtained 45 distinct crustacean prey sequences, from which only 20 taxa could be identified from the BOLD and GenBank databases. The matches were primarily to Decapoda but only a single taxon could be identified to the species level, Euphausia americana., Conclusions/significance: This technique proved to be an efficient and useful method, especially since prey species could be identified from partially-digested remains. The primary limitation is the lack of comprehensive coverage of potential prey species in the region in the BOLD and GenBank databases, especially among invertebrates.

Background: In contrast to the well-studied continental shelf region of the Gulf of Maine, fundamental questions regarding the diversity, distribution, and abundance of species living in deep-sea habitats along the adjacent continental margin remain unanswered. Lack of such knowledge precludes a greater understanding of the Gulf of Maine ecosystem and limits development of alternatives for conservation and management., Methodology/principal Findings: We use data from the published literature, unpublished studies, museum records and online sources, to: (1) assess the current state of knowledge of species diversity in the deep-sea habitats adjacent to the Gulf of Maine (39-43°N, 63-71°W, 150-3000 m depth); (2) compare patterns of taxonomic diversity and distribution of megafaunal and macrofaunal species among six distinct sub-regions and to the continental shelf; and (3) estimate the amount of unknown diversity in the region. Known diversity for the deep-sea region is 1,671 species; most are narrowly distributed and known to occur within only one sub-region. The number of species varies by sub-region and is directly related to sampling effort occurring within each. Fishes, corals, decapod crustaceans, molluscs, and echinoderms are relatively well known, while most other taxonomic groups are poorly known. Taxonomic diversity decreases with increasing distance from the continental shelf and with changes in benthic topography. Low similarity in faunal composition suggests the deep-sea region harbours faunal communities distinct from those of the continental shelf. Non-parametric estimators of species richness suggest a minimum of 50% of the deep-sea species inventory remains to be discovered., Conclusions/significance: The current state of knowledge of biodiversity in this deep-sea region is rudimentary. Our ability to answer questions is hampered by a lack of sufficient data for many taxonomic groups, which is constrained by sampling biases, life-history characteristics of target species, and the lack of trained taxonomists.

Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species) were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaíba Environmental Protection Area, in the States of Piauí and Maranhão, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus) and aquaculture activities (L. vannamei and M. rosenbergii) in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat). Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native redlip blenny Ophioblennius atlanticus and other fishes, such as the frillfin goby Bathigobius soporator Some immediate remedial measures to prevent further introductions from ballast water and shrimp farm ponds should be: (i) to prevent the release of ballast water by ship/vessels in the region; (ii) to reroute all effluent waters from shrimp rearing facilities through an underground or above-ground dry well; (iii) to install adequate sand and gravel filter which will allow passage of water but not livestock; (iv) outdoor shrimp pounds located on floodable land should be diked, and; (v) to promote environmental awareness of those directly involved with ballast water (crews of ship/vessels) and shrimp farms in the region.

The epibenthic community of the Minho Estuary was studied during the summer of 2006. Diversity was generally low and a total of 14 fish and five crustacean taxa were identified. Multivariate analysis revealed two site clusters (A and B). Water conductivity and percentage of fine sand were the abiotic variables that most contributed to the spatial distinction between clusters. The species contributing the most to the average similarity within Cluster A were Crangon crangon and Pomatoschistus microps, while in Cluster B was Atyaephyra desmarestii. Possible factors responsible for the low diversity of the epibenthic community in Minho Estuary were the low macrozoobenthic abundance and diversity, and the high abiotic oscillations between tides (mainly salinity) acting on the ecosystem., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The species of fish and macro-crustacean living within the Severn Estuary are reviewed. The fish community is notably species rich and exceeds 100 species in total for the estuary. Standardised long-term sampling at Hinkley Point in Bridgwater Bay gives a total complement of 83 for a single locality and this number is increasing by about one new species every two years. Most of these new species are moving in from centres of population lying to the south of the estuary. Almost all species of fish and macro-crustacean living within the estuary undertake regular migrations so that they tend to move seasonally in waves up and down the estuary. For fish, both species richness and the total abundance reach a maximum in late summer and autumn. The timing of this peak varies between the upper and lower estuary. This seasonal maximum is primarily caused by the arrival of the new recruits which use the estuary as a nursery. In contrast, crustaceans tend to be at their most diverse and abundant in early to mid summer. Using a 30-year time series of fish and crustacean abundance collected at Hinkley Point it is shown that major changes in the structure of the community are now underway and there are considerable recent changes in the abundance. However, some abundant species, including sand goby, Pomatoschistus spp., whiting, Merlangius merlangus and sprat, Sprattus sprattus, the three most abundant species in the estuary, have shown no long-term trend. At present, approximately 20% of the fish and macro-crustaceans observed in Bridgwater Bay are undergoing rapid, typically exponential, change in abundance. For a numerically abundant, diverse, fauna composed of approximately 90 species such levels of change are unexpected and suggest that the system is presently far from equilibrium. In some cases, the observed changes can be related to recent warming and the North Atlantic Oscillation. The overall increase in fish abundance observed may reflect a general improvement in water quality and a reduction in other anthropogenic impacts such as mortality in cooling-water intakes. The potential impacts of tidal power generation in the Severn Estuary are reviewed. There is considerable potential for any major installation to impact the fish and crustacean populations as they migrate and also alter the nature of the habitat resulting in changes in community composition. A particular difficulty in predicting the future impact of harnessing tidal energy is that the present community is already changing rapidly. The ability of fish and crustaceans to pass through the turbines unharmed will be a key issue in an assessment of the impact of tidal power generation., ((c) 2010 Elsevier Ltd. All rights reserved.)

The checklist of Crustacea and water mites (Hydracarina) parasitizing fishes in the Volga River basin is presented. Hosts and areas of distribution are indicated for each parasite species. The checklist includes 20 species and 1 subspecies of parasitic Crustacea, and 8 species of water mites from 41 fish species. Five species of Crustacea, (Paraergasilus medius, Neoergasilus japonicus, Sinergasilus lieni, S. major and Lernea elegans morpha ctenopharyngodonis are considered as invaders.

An extensive survey of helminth parasites in fish species from Tres Palos Lagoon, in Guerrero, Mexico, resulted in identification of 39 metazoan parasite species (37 helminth and 2 crustaceans) in 13 fish species (n = 1,498). Specimen collection in this coastal lagoon was done between April 2000 and November 2003. Digenean species (18, 8 adult and 10 metacercariae) dominated the parasite fauna. The most widespread species of parasite were: Contracaecum sp. (Nematoda), Pseudoacanthostomum panamense, Austrodiplostomum compactum, Ascocotye (Phagicola) longa (Digenea), Neoechinorhynchus golvani (Acanthocephala), Ergasilus sp. (Copepoda), and Argulus sp. (Branchiura). Parasite fauna species composition exhibited a clear freshwater influence as 56.4% (22 of 39) of the identified species have a freshwater distribution in Mexico. For 32 of the parasite species, this report constitutes the first geographical host record for Tres Palos Lagoon, Guerrero, Mexico.

Structural patterns of a sublittoral community were analyzed through a two-year series of samples in the Southwestern Gulf of Mexico. The groups involved in the study comprise fishes, molluscs, echinoderms and crustaceans. The time-space progressions of Second Order diversity values range between N2=5.3 and N2=9.8 at depths of 40 and 20 m respectively, through the first year of samples. In the second year the highest value (N2=22.2) was found at 30 m. The community ordination data through cluster and principal components analysis show five assemblages: benthic, benthic-demersal, demersal, mid water column, and temporary. There is a striking difference in trophic web structure between the dry season and rainy season. Fish community resource partitioning shows that the components are organized in three guilds: ichthyophagous, carcinophagous and omnivorous. However, a partial overlap of niches was commonly observed, and juvenile stages showed a narrower trophic spectrum than adults.

The present study is the first investigation on ectoparasites of commercial important fish from Segara Anakan, a brackish water lagoon located at the southern coast of Java, Indonesia. Eight economically important marine fish species (Mugil cephalus, Siganus javus, Scatophagus argus, Caranx sexfasciatus, Lutjanus johnii, Eleutheronema tetradactylum, Johnius coitor, and Epinephelus coioides) were examined for crustacean parasites. Prevalence and intensity data for each parasite species are given, together with an analysis of the origin and possible transmission pathways. A highly divers copepod fauna consisting of 23 different species and two isopods was found. All fish species were at least infested with two copepod species, with the exception of L. johnii, S. argus, and M. cephalus. With seven and six species, respectively, they harboured the most species-rich ectoparasite fauna. The copepods Ergasilus sp. 3 and Caligus acanthopagri on S. argus showed the highest prevalence (78.6) and intensity [17.8 (1-233) and 5.3 (1-22)] of infestation. The recorded parasite fauna is represented by marine, brackish water, and probably also freshwater components. The brackish water environment of Segara Anakan does not prevent disease outbreaks due to parasitic copepods by preventing pathogenic marine or freshwater species to enter the lagoon. This might cause fish health problems if the Segara Anakan Lagoon would be developed for finfish mariculture in future.

Recognition of the limited biological resources and the increasing environmental pollution has emphasised the need for better utilisation of by-products from the fisheries. Currently, the seafood industry is dependent on the processing of the few selected fish and shellfish species that are highly popular with consumers but, from economic and nutritional points of view, it is essential to utilise the entire catch. In this review, we will focus on recent developments and innovations in the field of underutilised marine species and marine by-product upgrading and, more precisely, on two aspects of the bioconversion of wastes from marine organisms, i.e. extraction of enzymes and preparation of protein hydrolysates. We will deal with the question of accurate determination of fish species at the various steps of processing. Methods of genetic identification applicable to fresh fish samples and to derived products will be described.

A total of 142 individuals of Gasterosteus aculeatus L. and 22 individuals of Pungitius pungitius (L.) from several areas of the coastal waters of the Gdańsk Bay both brackish- and freshwater were examined for parasites. The survey was carried out within 1988-1991. Six parasite species, namely: Gyrodactylus arcuatus, Apatemon gracilis, Sphaerostomum bramae, Phyllodistomumfolium, Neoechinorhynchus rutili, and Argulus foliaceus were recovered from sticklebacks caught in freshwater habitats; while the other 4 parasites: Apatemon annuligerum, Bothriocephalus sp., Schistocephalus solidus, Proteocephalus percae occurred only in fish from brackish-water areas. Additional 5 parasites: Trichodina domerguei, Diplostomum pungitii, Diplostomum spathaceum, Rhaphidascaris acus, and Thersitina gasterostei were recorded in fishes from both habitats.

Crustaceans (5 families, 10 species) and fish (38 families, 101 species) were captured (October 27 through November 3, 1979) from the R/V "Vikheim" (Cruise 7901) in the Colombian Caribbean, at a 10-630 m, depth range (Metapeneopsis shrimp, 26 species of fishes new for the trawling bottom and, Squalus cubensis, Chlorophthalmus agassizi, and, Neoepinnula orientalis), new fishes records for the Caribbean of Colombia.

Biodiversity of North American freshwaters is among the greatest in the world. However, due to extensive habitat degradation, pollution, and introductions of nonindigenous species, this biodiversity is also among the most endangered. Unlike habitat degradation and pollution, nonindigenous species represent a permanent loss of biodiversity because their removal or control is often impossible. Most species introduced into nonnative North American ranges, however, are not from Eurasia but have been introduced from geographically isolated regions within North America. Although the ecological effects of introduced species have been widely documented, the effects of hybridization, especially between closely related species, represents an equally serious mechanism of extinction but is much less studied. Identification of which species are likely to hybridize after contact is of critical importance to prevent the further loss of native species. Molecular phylogenetics serves as a powerful tool to identify freshwater species at risk of introgression, if we can assume that genetic distance is a good predictor of the potential for hybridization. Although not a thorough review of all cases of hybridization, this article documents the extent and effects of hybridization in fishes, crayfishes, mussels, and other invertebrates in light of the currently accepted phylogenetic relationships. We suggest this approach may be the first step in addressing the potential threat of hybridization between many of the closely related species in North American fresh waters.

Four new Ergasilus species are described from five host species of grey mullet, family Mugilidae, held in the fish collections of The Natural History Museum, London. Ergasilus extensus n. sp. was found on Myxus petardi (Castelnau) from Australia, E. sittangenesis n. sp. on Sicamugil hamiltoni (Day) from Burma, E. piriformis n. sp. on Sicamugil cascasia (Hamilton Buchanan) from India, and E. ecuadorensis n. sp. on Mugil curema Valenciennes and M. hospes Jordan & Culver from Ecuador. New records of E. cyanopictus Caravalho, E. magnicornis Yin, E. orientalis Yamaguti and E. rostralis Ho, Jayarajian & Radhakrishnan on grey mullet are also given.

The Baltic Sea is characterized by organisms that can tolerate brackish water. Because of the Sea's history during glacial times, its flora and fauna (and also their parasites) can be traced to marine, freshwater and genuine brackish elements beside glacial relics. Snails, planktonic copepods, benthic amphipods and isopods are important intermediate hosts of diverse helminths; in addition polychaetes, bivalves and fishes may also act as final hosts. The most important final hosts, beside fishes, were seals and birds; these were able to disperse the parasites over the whole of the Baltic. Decreasing salinity from west to east limits the distribution of many parasites. Several marine and genuine brackish water species have almost spread over the whole Baltic. Freshwater species, however, have a lower tolerance than marine species and are only rarely found in the western part. A serious problem in the Baltic is eutrophication which can lead to massive abundances of generalist parasites, in host populations as well as host individuals. The final stage of this influence can cause a general decrease of host abundance and, as a consequence, of all kinds of parasites, due to oxygen deficiency. In comparison with the species spectrum of other brackish waters in Europe, the Baltic presents some endemic parasites as well as sharing parasite species with the Mediterranean and even the Black Sea.

Three new species of Hatschekia are described from the gill filaments of fishes taken in the Persian Gulf: H. seyi n. sp. from Heniochus acuminatus (Linnaeus), H. nodosa n. sp. from Lutjanus coccineus (Cuvier) and H. tanysoma n. sp. from L. fulviflamma (Forsskål). H. seyi differs from its congeners in having the cephalothorax longer than the trunk; H. nodosa, in having multiple nodules on the posterolateral margins of the trunk; and H. tanysoma, in having the trunk more than six times the length of cephalothorax and some pinnate setae on legs 1 and 2.

Haemogregarina bigemina Laveran et Mesnil, 1901 was examined in marine fishes and the gnathiid isopod, Gnathia africana Barnard, 1914 in South Africa. Its development in fishes was similar to that described previously for this species. Gnathiids taken from fishes with H. bigemina, and prepared sequentially over 28 days post feeding (d.p.f.), contained stages of syzygy, immature and mature oocysts, sporozoites and merozoites of at least three types. Sporozoites, often five in number, formed from each oocyst from 9 d.p.f. First-generation merozoites appeared in small numbers at 11 d.p.f., arising from small, rounded meronts. Mature, second-generation merozoites appeared in large clusters within gut tissue at 18 d.p.f. They were presumed to arise from fan-shaped meronts, first observed at 11 d.p.f. Third-generation merozoites were the shortest, and resulted from binary fission of meronts, derived from second-generation merozoites. Gnathiids taken from sponges within rock pools contained only gamonts and immature oocysts. It is concluded that the development of H. bigemina in its arthropod host illustrates an affinity with Hemolivia and one species of Hepatozoon. However, the absence of sporokinctes and sporocysts also distances it from these genera, and from Karyolysus. Furthermore, H. bigemina produces fewer sporozoites than Cyrilia and Desseria, although, as in Desseria, Haemogregarina (sensu stricto) and Babesiosoma, post-sporogonic production of merozoites occurs in the invertebrate host. The presence of intraerythrocytic binary fission in its fish host means that H. bigemina is not a Desseria. Overall it most closely resembles Haemogregarina (sensu stricto) in its development, although the match is not exact.

The stages in the metamorphosis of the pennellid Cardiodectes medusaeus (Wilson) are described from mid-water fishes in the Indo-Pacific. The earliest metamorphic stage was found within the body cavity of the second host and indicates a double origin for the frontal processes of the cephalic holdfast in this species. A new species of Lophoura (family Sphyriidae) is described from a single female taken from a deep-water synaphobranchid eel caught in the North Atlantic. The new species, L. simplex, is characterised by the lack of any neck processes. Another sphyriid, Periplexis lobodes Wilson, is reported for the second time. It was found on a deep-sea alepocephalid belonging to the genus Rouleina in Fijian waters.

The female of Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the "jundiá," Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment).

In order to establish the distribution and abundance of demersal fishes and of some other benthic organisms on the continental shelf of French Guiana (western central Atlantic), ninety-five bottom trawls were effected at depths ranging from 0 to 60 m in October 1993. A total of one hundred and ten different species were identified including eight decapod crustaceans, two cephalopods, one sea turtle and ninety-nine fishes. Despite the high species richness in benthic macrofauna, most species showed a low count, and only twelve of them comprised more than 80% of total captures. This study has mainly highlighted the existence of a well-pronounced bathymetric zonation. This phenomenon would appear to be linked to environmental factors, especially salinity and substrate granulometry, which are greatly conditioned by fresh water and sediment flowing in large rivers such the Amazon River. The results revealed three distinct faunistic assemblages: a littoral (or shallow-water) community (0-30 m) distributed in coastal estuarine waters characterized by muddy bottoms, a middle-shelf community (30-50 m), and a lower-shelf community (depths > 50 m) distributed in deeper marine waters characterized by sandy bottoms.

Six species of copepods of the genus Caligus (Caligidae, Siphonostomatoida) parasitic on marine fishes of Taiwan are reported. They are: C. absens n. sp. from Priacanthus blochii and P. macracanthus; C. epinepheli Yamaguti, 1936 from Scolopsis vosmeri; C. kanagurta Pillai, 1961 from Decrapterts kurroides; C. laticaudus Shiino, 1960 from Lutjanus vitta and Parapristiopoma trilineatum; C. nengai Rangnekar, Rangnekar & Murti, 1953 from Triacanthus biaculeatus; and C. rotundigenitalis Yü, 1933 from Drepane punctata, Liza macrolepis and Terapon jarbua. C. distortus Pillai & Natarajan, 1977 is relegated to a synonym of C. nengai and C. multispinosus Shen, 1957 reported by Lin et al. (1994) from the cultured sea bream Acanthopagrus schlegeli is a misidentification for C. rotundigenitalis Yü, 1933.

The study of the cymothoid isopod parasites on marine fishes from Tunisian localities has allowed us to distinguish eight species, seven of which have already been recorded and one, Mothocya epimerica which is new to the region. New hosts for Cerathotoa parallela and Nerocila orbignyi are reported. For each parasite species collected, the host fish, the parasitic specificity and the parasitological index are given.

The report contains the results of faunistic study of parasitic Hirudinea, Mollusca, Crustacea and Arachnida occurring on fishes in the region of the S. Dvina, Mezen' and Pechora river basins. The parasite fauna in the first basin is represented by 3 species of leeches, 4 species of molluscs, 13 species of crustaceans and 1 species of water mites, in the second basin--4, 1, 11, 0; in the third basin--2, 7, 7, 1 species respectively. Total number of parasites in the region investigated: 4 leech species, 5 molluscs species, 16 crustacean species and 1 water mite species.

A new species of caligid copepod (Siphonostomatoida), Anuretes grandis sp. n., parasitic on the painted sweetlips [Diagramma pictum (Thunberg)] in Taiwan is described. The new species is distinguished from its congeners by having: (1) free margin of cephalothorax not covering fourth pediger, (2) large genital complex longer than 2/3 of the cephalic shield, (3) no maxillary whip, (4) leg 3 with 9 setae on the terminal segment of exopod and 8 plumose setae on the terminal segment of endopod, and (5) armature of I,III on leg 4 exopod. Genus Anuretes Heller, 1865 is reviewed and redefined. Based on the new diagnosis three species (A. chelatus Prabha et Pillai, A. fedderni Price and A. parvulus Wilson) were transferred to Pseudanuretes, and two species (A. furcatus Capart and A. renalis Heegaard) were transferred to Lepeophtheirus. In addition, the following three species of caligids were transferred to Anuretes: Lepeophtheirus fallolunulus Lewis, Heniochophilus indicus Pillai, and Lepeophtheirus rotundigenitalis Prabha et Pillai. The latter is renamed Anuretes occultus nom. n. due to the homonym encountered through this transfer. "Anuretes plectorhynchi Yamaguti" reported by Prabha and Pillai (1986) is renamed Anuretes similis sp. n. and Anuretes yamagutii Prabha et Pillai is relegated to the synonym of Anuretes anomalus Pillai. A key to the 18 species of Anuretes is provided.

Chondracanthid copepods parasites 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 prevalence 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.

A list of the species and taxa of some pelagic animals from a tropical upwelling region, based on collections made off the coast of Costa Rica is presented. The list includes a total of 224 species, 53 genera and 11 subspecific forms in Cnidaria, Annelida, Mollusca, Artropoda (Crustacea), Chaetognatha and Pisces.

Adult male and female Argulus melanostictus Wilson, 1935 are redescribed based on detailed examinations of a syntype and recently obtained specimens of both sexes collected from California grunion, Leuresthes tenuis, captured in nearshore Pacific waters at Monterey, California. A 14-16-hr seawater bath containing 0.5 microliter/L trichlorfon administered once weekly for 3 wk killed A. melanostictus while not noticeably harming grunion.

Six of the 10 recognised families of the order Cyclopoida are parasitic, with 4 of them occurring on marine invertebrates and the remaining 2 on freshwater gastropods and fishes, respectively. A cladistic analysis of the 10 families indicates that evolution of parasitism occurred twice in the history of the cyclopoids. The first attempt was made by the marine epibenthic ancestors seeking food and shelter in sessile tunicates--the ascidians. This event led to the evolution of 2 ascidicolous families: Archinotodelphyidae and Notodelphyidae. The descendant of this lineage had also invaded the mantle cavity of marine bivalve molluscs, eventually leading to the evolution of the Mantridae. The second attempt for the parasitic mode of life was launched by the ancestor which was the sister group of the ancestral cyclopoids--the most successful family of freshwater copepods. This ancestral stock, while living in the coastal zone, split into 2 groups: one group stayed behind in the ocean and colonised again the ascidians; the other groups invaded freshwater and evolved into the fish-parasitising Lernaeidae and the gastropod-parasitising Ozmanidae.

45 species of Copepoda and 14 of Isopoda have been found on the South Adriatic (Montenegrian coast) fishes during the 10 years study. In addition to the check-list, some results of pathological and haematological investigations, showing that these parasites have a considerable impact on the growth, condition index and physiological state of hosts, are given.

Fish from the north-east Atlantic, including neighbouring aquens are host of 3 species of Branchiura, 163 Copepoda, 37 Isopoda, 2 Amphipoda, and 1 of parasitic Cirripedia. Chondrichthyes have more species of parasitic crustaceans than Osteichthyes. Many specific parasites of Osteichthyes and the facultative parasites of fish include species of crustaceans to fish of both classes. 165 species of parasitic crustaceans are found in benthic and near-benthic fish, and 55 in pelagic fish. The greatest variety of species parasitic crustaceans is found in fishes in the North Sea (139); it is much smaller in the Baltic Sea (15). Endemic species constitute 15% of the total number of parasitic crustacean. The irregular distribution of parasitic crustaceans is among others connected with the biology and ecology of both hosts and their parasites.

The following classification of body form typical for parasitic copepods which could be useful when compiling the determinants describing supraspecific taxon was proposed. The cyclopoid body form for the families Bomolochidae, Taeniacanthidae, Ergasilidae, Myicolidae, Tegabomolochidae, Telsidae and Grandiunguidae; caligoid body form for Caligidae, Pandaridae, Euryphoridae, Cecropidae, Scienophilidae, Trebiidae and Dissonidae; eudactyloid body form for Eudactylinidae, Hatschekiidae and Pseudocynidae; the chondracanthoid body form for Hyponeoidae, Shiinoidae, Pharoidae and some Chondracanthidae; the lernanthropoid body form for Lernanthropidae and Anthosomatidae; the lernaeopodidoid body form for Lernaeopodidae and Naobranchiidae; the sphyriioid body form for Sphyriidae, Lernaeidae, Pennellidae and some Chondracanthidae; the philichthyioid body form for Philichthyidae are discussed.

In the Caspian Sea were found typically marine form--Pseudotracheliastes stellatus, specific for Acipenseridae, Thersitina gasterostei typical for sticklebacks rather euryhaline hosts, and Ergasilus briani, E. sieboldi, Paraergasilus rylowi, Lernaea elegans, L. esocina, Caligus lacustris, Argulus coregoni, A. foliaceus and Achtheres percarum normally infested the fishes in fresh water. The last one is characteristic for only Percidae, the remaining fresh-water crustaceans have far more wide host range. The majority of the parasitic crustaceans are noted in the coastal shallow areas of the Caspian Sea. Only P. stellatus is met too in the fairy deep places, where they are brought by Acipenseridae, which perform migrations of considerable extent.

In the course of ichthyological inventory investigations in the main water-course of the Narew River the occurrence of Tracheliastes polycolpus Nordm. was recorded on ide Leuciscus idus (L.) and pike Esox lucius L. A comparison of the occurrence of this parasite in other rivers of Poland is presented.

A total of 429 individuals of three fish families: Clupeidae, Cyprinidae and Percidae were subjected to parasitological investigation. All fishes were from retail shops were they had been kept frozen. The parasites found belong to the groups Monogenea, Trematoda, Cestoda, Nematoda, Acanthocephala, Hirudinae and Crustacea. Almost all endoparasites were localized in the intestines, the ectoparasites on the gills or on the skin. The fishes investigated were slightly infected, but suitable for consumption. The majority of different species of parasites was found in fishes that shoal, which is quite concordant with "Janiszewska's rule".

The morphology of a copepodid found on Huso huso near the delta of the Volga is described and illustrated. The copepodid bears general resemblance to those of Caligidae but differs from them in absence of the frontal filament and in possession of a primitive first maxilla. It is concluded that the copepodid belongs to Dichelesthium oblongum and that Dichelesthiidae might be more closely related to Caligidae than has hitherto been suspected.

Auchenochondria lobosa gen. et sp. n. was recovered from the oral cavity of the California halibut, Paralichthys californicus (Ayers), collected in Agua Hedionda Lagoon, Carlsbad, California. The new genus is closely related to Prochondracanthus Yamaguti 1939, and Rhynchochondria Ho 1967, but can be distinguished from them by the possession of cephalothoracic processes, a long neck, a 2-segmented abdomen, and a distinctly 6-segmented first antenna. Auchenochondria lobosa gen. et sp. n. is the only known species of chondracanthid in which the mandible of the male is equipped with more teeth on both the convex and concave surfaces than that of the female.

Out of 29 species of fish from the Kerkennah Islands examined, 30 species of parasitic copepoda were collected which belong to seven families and nine different genera. Among them three new species have been found and ten were reported for the first time in Tunisia.