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At least 19 recordsLinked to original sources

The effects of the ectoparasite Tracheliastes polycolpus (Copepoda: Lernaeopodidae) on the fins of rostrum dace (Leuciscus leuciscus burdigalensis).

Rostrum dace (Leuciscus leuciscus burdigalensis) from the River Viaur were found to be infested with the ectoparasite Tracheliastes polycolpus (Copepoda: Lernaeopodidae). Samples from five study sites along the river revealed different patterns of parasite infestation. Heavily infested fish were found at the upper study sites whereas much lower infestation levels were observed at the lower study sites. The copepods showed an aggregated dispersion pattern on host fins. The results showed significantly preferred microhabitats, with adult females being more abundant on the anal, pelvic and along the external part of the pectoral fins. The anal and pelvic fins were damaged by the parasite with a loss of their surface area. These fin alterations may reduce the fish's swimming ability and therefore affect the rostrum dace population. Our findings highlight the need to study the effects of parasites on stream fish populations.

Animals↗

Description of Paeon asymboli n. sp. (Copepoda: Sphyriidae), parasitic on Asymbolus spp. (catsharks) and a new host record for P. australis Kabata, 1993.

Paeon asymboli n. sp. (Copepoda: Sphyriidae) is described and illustrated from two female specimens taken from the gills of a grey spotted catshark Asymbolus analis (Ogilby) and an orange spotted catshark A. rubiginosus (Last, Gomon & Gledhill) (Scyliorhinidae) from off southeastern Queensland, Australia. The key features for identification are: a pear-shaped trunk, longer than it is wide, along with a cephalothorax characterised by two large ventral papillae, projecting laterally and supporting a number of secondary lobes; a single mid-line, sub-conical papilla located antero-dorsal to the ventral papillae; an anterior surface bearing two prominent stalked papillae; and an absence of posterolateral lobular processes. P. australis Kabata, 1993 is recorded for the first time from the eastern shovelnose ray Aptychotrema rostrata (Shaw & Nodder) (Rhinobatidae).

Animals↗

A new species of Acantholochus (Copepoda: Bomolochidae) parasitic on Centropomus undecimalis (Osteichthyes: Centropomidae) from the coastal zone of the State of Rio de Janeiro, Brazil.

A new species of Acantholochus Cressey, 1984 (Copepoda: Bomolochidae) parasitic on the gills of common snook, Centropomus undecimalis, from the coastal zone of the State of Rio de Janeiro, Brazil, is described and illustrated. The new species differs from all other species of Acantholochus by the presence of only one inner seta on middle segment of the second and third endopods.

Animals↗

Argentinochondria patagonensis n. gen., n. sp. (Copepoda: Chondracanthidae) parasitic on Genypterus brasiliensis (Pisces: Ophidiidae) from Patagonia, Argentina.

Argentinochondria patagonensis n. gen., n. sp. (Copepoda: Chondracanthidae) is described from adult specimens recovered from the smooth kingklip Genypterus brasiliensis Reagan, 1903, from San Jorge Gulf, Patagonia, Argentina. The new genus is placed in the Chondracanthinae. Females of the new genus differ from other members of this subfamily in having 2 pairs of modified legs, a bulbose head, a long neck region, and a trunk devoid of processes. Males have usual chondracanthid form, oral appendages as in female, except a longer paragnath, fewer teeth on maxilla, and 2 pairs of reduced legs.

Animals↗

Schistobrachia jordaanae n. sp. (Copepoda: Siphonostomatoida: Lernaeopodidae) from gill filaments of a diamond ray (Gymnura natalensis) captured in the Indian Ocean and a key to species of Schistobrachia, Dendrapta, and Brianella.

Schistobrachia jordaanae n. sp. (Copepoda: Siphonostomatoida: Lernaeopodidae) is described from adult female specimens collected from gill filaments of a diamond ray Gymnura natalensis (Gilchrist and Thompson, 1911) captured in the Indian Ocean off the South African coast. Schistobrachia jordaanae is best distinguished from its congeners by 2 unique characteristics: it possesses a necklike region between the origin of its maxillae and maxillipeds and the tips of its maxillae bifurcate repeatedly to form a rootlike anchor.

Animals↗

New species of Metacaligus (Caligidae, Copepoda) parasitic on the cutlassfish (Trichiurus lepturus) of Taiwan, with a cladistic analysis of the family Caligidae.

Metacaligus latus n. sp. (Copepoda, Caligidae) is described from specimens found parasitic in the oral and gill cavities of the cutlassfish, Trichiurus lepturus Linnaeus, caught from the Strait of Taiwan and landed at Dong-Shih Fishing Port in Chiayi County, Taiwan. It is close to M. uruguayensis (Thomsen, 1949), but can be distinguished from the latter by the possession of shorter caudal rami in both sexes and wider cephalothorax and genital complex in the male. Cladistic (phylogenetic) analysis of the Family Caligidae, based on 23 selected morphological characters, revealed that Metacaligus Thomsen, 1949 is distantly related to Caligus Müller, 1758. It is a valid genus and occurs in sister-group relationship with Apogonia Cressey and Cressey, 1990.

Animals↗

Fertilization envelope in diapause eggs of Pontella mediterranea (Crustacea, Copepoda).

The sequence and timing of morphological changes during envelope formation was followed in diapause eggs of Pontella mediterranea (Crustacea, Copepoda). The multilayer coat enveloping these eggs resulted from the exocytosis of 4 types of cortical vesicles that sequentially released their contents in the perivitelline space. These included small high-density vesicles (hDV) with electron-dense material, vesicles (V) with dense ring granules and a uniform matrix contained within the same compartment, large high-density (HDV) vesicles, and large moderately dense (MDV) vesicles. All of these cortical vesicles were present in newly spawned, fertilized eggs. Their exocytosis resulted from egg activation. One of these cortical vesicles (V) was similar in morphology to the intracisternal granules precursors of endogenous yolk. Intracisternal granules, characteristic of previtellogenic oocytes of many crustaceans, were present in previtellogenic oocytes of P. mediterranea but disappeared in later stages of oocyte development once yolk formation was completed. We discuss the role of cortical vesicles in the formation of the complex extracellular coat enveloping copepod diapause eggs.

Adaptation, Physiological↗

The distribution and abundance of Lernaeocera lusci (Copepoda) on hake (Merluccius merluccius) and bib (Trisopterus luscus) (Teleostei).

Distribution patterns, mean intensity and prevalence of Lernaeocera lusci (Copepoda, Pennellidae) in its hosts Trisopterus luscus (Teleostei, Gadidae) and Merluccius merluccius (Teleostei Merlucciidae) were examined, together with parasitic abundance and aggregation in relation to the size of the host. The mean parasite abundance and variance to mean abundance ratio increased with host size, suggesting that the accumulation of this parasite had no noticeable impact on the structure of either host population. Merluccius merluccius being a newly colonized host in the Mediterranean, these results are discussed in relation to current ideas on the evolution of pathogenicity in heterospecific associations.

Animals↗

Margolisius abditus n. gen., n. sP. (Copepoda: Lernaeopodidae) from gill lamellae of a remora (Remora remora) collected in the Gulf of California.

Margolisius abditus n. gen., n. sp. (Copepoda: Lernaeopodidae) is described from female specimens collected from gill lamellae of a remora, Remora remora (L.), captured in the Gulf of California near Punta Arena, Baja California. Comparison of this species with 13 lernaeopodid genera with which it shares (a) absence of posterior trunk processes; (b) presence of a relatively long cylindrical cephalothorax, usually reflected along the dorsal surface of the trunk; and (c) a marine habitat showed that it cannot be placed in any of them, thus necessitating establishment of a new genus. Margolisius abditus n. sp. is the smallest known lernaeopodid species, its ovigerous females measuring about 0.5 mm in total length.

Animals↗

Effect of Triaenophorus crassus (Cestoda) infection on behavior and susceptibility to predation of the first intermediate host Cyclops strenuus (Copepoda).

Some parasites have been shown to manipulate host behavior so that parasite transmission to the next host is enhanced. Infection with Triaenophorus crassus Forel (Cestoda) caused alterations in the activity and microhabitat selection of the first intermediate host Cyclops strenuus Fischer (Copepoda) in the laboratory. Infected copepods made more starts to swim but spent less time swimming than uninfected copepods. These changes were independent of the intensity of infection. In a water column illuminated from above, infected copepods approached the surface, whereas uninfected ones remained close to the bottom. In the dark both infected and uninfected copepods stayed near the bottom. Finally, infection with T. crassus increased the probability of C. strenuus being eaten by the second intermediate host, whitefish (Coregonus lavaretus L. s.l.), in the laboratory. In experimental infections, 10-day-old procercoids had significantly lower infectivity for whitefish than older (12-, 14-, and 21-day-old) procercoids. Behavioral changes were detected in infected copepods containing procercoids 12 days old or older but not in experiments with 10-day-old procercoids. These results may indicate that T. crassus changes the behavior of the copepod host only after it has become infective to the next host, which is consistent with the active manipulation hypothesis.

Analysis of Variance↗

Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) from the gills of Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae) from southern Brazil.

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).

Animals↗

Kroeyerina deetsorum n. sp. (Copepoda: Kroyeriidae) from the olfactory sacs of Atlantic sharpnose sharks (Rhizoprionodon terraenovae) captured in the Gulf of Mexico and northwestern Atlantic and first report of copepodids representing Kroyeriidae.

Kroeyerina deetsorum n. sp. (Copepoda: Kroyeriidae) is described from female and male specimens collected from the olfactory sacs of Atlantic sharpnose sharks, Rhizoprionodon terraenovae (Richardson, 1836), captured in the Gulf of Mexico and northwestern Atlantic. Kroeyerina deetsorum is easily distinguished from known congeners by the extremely small size of its adults (i.e., females about 1.2 mm total length and males about 1.0 mm total length). Kroeyerina deetsorum is also distinguished from its congeners by possessing a subquadrate rostrum without lobes or upturned horns. It is suspected that K. deetsorum belongs to a clade within Kroeyerina whose members only infect sharks. This report also provides first descriptions of a nauplius representing Kroeyerina and copepodids representing Kroyeriidae. The early-stage copepodid of K. deetsorum lacks a frontal organ and frontal filament and uses its chelate antennae to attach to its host.

Animals↗

Taeniacanthodes dojirii n. sp. (Copepoda: Poecilostomatoida: Taeniacanthidae), from Cortez electric rays (Narcine entemedor: Torpediniformes: Narcinidae) captured in the Gulf of California, and a phylogenetic analysis of and key to species of taeniacanthodes.

Taeniacanthodes dojirii n. sp. (Copepoda: Poecilostomatoida: Taeniacanthidae) is described from adult female specimens collected from the body surface of Cortez electric rays Narcine entemedor (Torpediniformes, Narcinidae), captured at several locations in the Gulf of California. Taeniacanthodes dojirii is distinguished from its congeners, as well as from other members of Taeniacanthidae, by possessing unimerous fifth legs. A cladistic analysis of the 3 known species of Taeniacanthodes resulted in a single most parsimonious tree (tree length = 18 steps, consistency index = 1) demonstrating that T. gracilis and T. haakeri, both parasites of benthic teleosts, are more closely related to each other than to the new species.

Animals↗

Prevalence of Mytilicola intestinalis (Copepoda: Mytilicolidae) and Urastoma cyprinae (Turbellaria: Hypotrichinidae) in marketable mussels Mytilus galloprovincialis in Italy.

Marketable mussels Mytilus galloprovincialis traded with commercial certification from production sites in Italy and abroad (France, Spain) were examined for the presence of Mytilicola intestinalis (Copepoda: Mytilicolidae) and Urastoma cyprinae (Turbellaria: Hypotrichinidae) from October 1994 to February 1996. The prevalence of M. intestinalis was 4.1% and 4.7% respectively in mussels from Lerici (La Spezia) and S. Pietro in Volta (Venice), whereas it rose to 57.9% in the samples from Spain. M. intestinalis was absent in mussels from Chioggia (Venice), Ganzirri (Messina), Taranto, Trieste and France. The prevalence of U. cyprinae varied considerably, ranging from 0.3% in mussels from Trani (Bari) to 33.2% and 86.3% respectively in those from Chioggia and Trieste. It was 85.7% in samples from France and 63.7% in those from Spain.

Animals↗

New host and ocean records and remarks on the morphology and behavior of Jusheyus shogunus (Copepoda: Siphonostomatoida: Eudactylinidae.

Jusheyus shogunus Deets and Benz, 1987 (Copepoda: Eudactylinidae) is reported from wreckfish, Polyprion americanus (Schneider, 1801) collected from widely separated locations in the north Atlantic. This represents a new host record and new ocean report for this parasite. Examination of male and female copepods allowed some confusion regarding the morphology of J. shogunus to be eliminated. Jusheyus shogunus possesses a cephalothorax rather than a cephalosome and its dorsal styliform processes are connected by an internal bridging sclerite and an external dorsal plate that is hinged to its cephalothorax. Each process also articulates with its own internal ventral sclerite. A series of muscles services these structures, and comparisons of the dorsal styliform processes of J. shogunus with the dorsal stylets of Kroyeria spp. revealed some morphological similarities. Adult female J. shogunus in the study collection varied in size from 2.16 to 4.97 mm total length, and smaller and larger specimens presented somewhat different body forms. Most egg sacs contained multiseriately arranged eggs; however, several specimens possessed a sac whose distal portion contained uniseriately arranged eggs and whose proximal portion contained 2 rows of eggs. Jusheyus shogunus attaches to the gill filament lamellae of its hosts using its second antennae and maxillipeds. The dorsal styliform processes can be erected by either directly raising them or by flexing the cephalothorax at its junction with the first free thoracic segment. In either case the tips of the processes can engage 1 to several lamellae on the adjacent gill filament to help secure the parasite.

Animals↗

[The peculiarities of parasitism in the copepoda and rhizocephala].

In the parasitology it is accepted to subdivide the parasites into two categories based on their spatial relations with the organism of a host. To first category--ectoparasites--includes organisms, which live "on external covers, on a skin, on gills". To the second category--endoparasites--includes organisms living "in internal cavities, tissues and cells of the host" (Dogiel, 1941). Feizullaev (1971) offered the third category--mesoparasites--where he placed "the parasites inhabiting places, which are connected to cavities being open to external environment". According to him the places are oral, nasal, eye cavity, cloaca etc. Since some parasitic copepods living in certain kind of interrelation with a host can be referred neither to ectoparasites nor to endoparasites, the author offers these following criteria for the mesoparasitism definition. 1. Morphological and anatomic subdivision of the body of the parasite into two main parts: ectosoma located in the external environment (environment of the second order) and endosoma located inside the organism of the host (environment of the first order). 2. Functional subdivision of parasite body into two parts: endosoma which performs the trophic function and ectosoma with genital organs performs the reproduction function. 3. Existence of the parasite on the border of two environments (of the first and second order) which have an influence on parasite directly and simultaneously. The mesoparasites are known among the parasitic Copepoda and Rhizocephala only. As for the copepods all members of the family Herpyllobiidae may be placed in this category; the members of the families Phyllodicolidae and Chitonophilidae may be also included in it, albeit tentatively (because their anatomy has not yet been adequately studied), as well as five genera of the family Nicothoidae (Aspidoecia, Cephalorhiza, Diexanthema, Nicorhiza and Rhizorhina), and Bradophyla pigmaea.

Animals↗

[Chromosomal radiosensitivity as associated with chromatin diminution in cyclops (Crustacea, Copepoda)].

Chromosomal radiosensitivity inferred from the yield of chromosome aberrations (CAs) was for the first time studied in Cyclops (Crustacea, Copepoda) before and after chromatin diminution (CD). A comparison was made for C. kolensis, in which CD denudes somatic embryo cells of the greatest (94%) DNA amount known for multicellular organisms, and C. insignis, which lacks CD. The two species have similar genome sizes, 4.6 and 4.3 pg. respectively. Radiosensitivity of C. kolensis chromosomes proved to be extremely high during prediminution cleavage divisions. This was attributed to membrane damage in granules that contain enzymes (topoisomerases) normally involved in cleavage and ligation of chromosomal DNA during CD.

Anaphase↗