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An organ located between bases of second antennae of an adult female of Achtheres percarum was found. Its fine structure based on SEM observations is described. It consist of four semirectangular pads covered with densely packed villiform papillae. It was concluded that the newly found organ serves for producing frontal filament, a larval attachment structure, as well as bulla, an attachment organ of adult females. Other described structures include: flap-shaped processes of the labrum, cephalic sensory papillae and vestigial thoracic legs.
Three parasitic copepods (Siphonostomatoida) belonging to three different genera were recovered from marine fishes of Iraq, and are listed here as new records. The sea lice Caligus epinepheli Yamaguti, 1936 (Caligidae) was collected from the Japanese threadfin bream, Nemipterus japonicus (Bloch). It had been frequently reported from teleost fishes around the world. The second record, comprising male and female, was another caligid, rarely caught from fishes — Hermilius longicornis Bassett-Smith, 1898, collected from the giant catfish, Netuma thalassina (Rüppell). This paper features the first description of the male of the latter species. The third record was the lernanthropid, Lernanthropinus temminckii (von Nordmann, 1864) (Lernanthropidae), redescribed based on the specimens collected from the greater lizard fish, Saurida tumbil (Bloch) (Synodontidae). In order to clarify its taxonomic status, our specimen was compared with the holotype of L. gibbosus (Pillai, 1964) from the collections of Zoological Survey of India, Kolkata, and the syntypes of L. sauridae Do in Ho and Do, 1985 and L. temminckii from the collections of the Smithsonian Institution, Washington D.C. We found similarities in the morphology of the body, mouthparts, and legs 1–4 in three above-mentioned species. The prominent feature, the setation pattern of legs 1 and 2 was similar in all the female specimens examined. In the light of this, we formally relegate L. gibbosus and L. sauridae to synonymy with L. temminckii. Another important similarity is that Lernanthropinus gibbosus, L. sauridae, and L. temminckii have exclusively been parasitic on lizardfishes (Synodontidae). The attachment site of all three copepods reported form Iraq were the gill filaments.
Neobrachiella spinicephala (Ringuelet, 1945) (Copepoda, Siphonostomatoida, Lernaeopodidae) is redescribed based on newly collected material from the Brazilian sandperch, Pinguipes brasilianus Cuvier, 1829, (the type host) from Mar del Plata, Argentina (the type locality). A description of the male is given for the first time. Although some differences were observed between the original description and the specimens examined in this study, these differences do not warrant a change in the taxonomic status of this species. Indeed, the generic status of the species is confirmed, especially based on characteristics of the male.
Background. Driocephalus cerebrinoxius is an unusual representative of an unusual family of parasitic copepods (Sphyriidae, Siphonostomatoida, Copepoda). This report documents new host and ocean records for D. cerebrinoxius and considers the phylogenetic relationships amongst sphyriid (Sphyriidae) genera.Materials and Methods. Copepods collected from trawl-caught fishes were studied using light microscopy and standard staining, manipulation, and measuring techniques. The phylogenetic analysis (parsimony outgroup analysis) was conducted using adult female morphological characteristics of sphyriid genera. Results. Driocephalus cerebrinoxius is reported for the first time from the Pacific Ocean and from the star-spotted smooth hound, Mustelus manazo (Triakidae, Carcharhiniformes). The cladistic analysis of sphyriid taxa resulted in 12 shortest trees, each with a length of 16 and consistency index of 0.875. Strict and majority rule consensus trees are presented. Conclusion. Due to the paucity of morphological characters available for analysis, a robust phylogenetic hypothesis for taxa comprising Sphyriidae is best sought using molecular tools. Without a robust phylogeny it is premature to undertake associated analyses regarding historical ecology within Sphyriidae.
Background. Thysanote Krøyer, 1863 (Copepoda, Siphonostomatoida, Lernaeopodidae) comprises 19 species of marine parasite that infect fishes. This report establishes a new Thysanote species based on new collections of copepods. The taxonomic status of this genus is not fully understood and therefore more relevant contributions are needed. Materials and Methods. The species description is based on male and female specimens collected from the olfactory sacs of spotted scat, Scatophagus argus, captured off Thailand in 2003. The specimens were studied using standard light and scanning electron microscopy techniques. Results. The studied specimens were assigned to Thysanote based on the presence of maxillary- and posterior processes and they exhibited unique characteristics such as distinctly short length of their maxillary- and posterior processes. Conclusion. Based on their unique characteristics, a new Thysanote species is erected, and named Thysanote chalermwati n. sp., thus bringing the number of congeners to 20.
It is argued that Penicillus indicus Kumar et Hameed, 1993 represents two species; a member of Pennella Oken, 1815 (Pennellidae, Siphonostomatoida, Copepoda) with lepadid (Lepadidae, Lepadomorpha, Cirripedia) phoronts attached to its abdomen. This conclusion, while not founded on examination of the type and only specimens of P. indicus, seems robust based on observations that: 1) the species description of P. indicus is unquestionably similar to a combination of the aforementioned copepod and barnacle taxa, i.e. one copepod with several attached barnacles, 2) records of Pennella representatives with attached striped goose barnacles, Conchoderma virgatum (Spengler, 1790) (Lepadidae) are well known, and 3) this interpretation explains why the type series of P. indicus exhibits considerable intraspecific variation regarding numbers of appendages and numbers and placement of unusual abdominal organs. Based on this explanation, it is recommended that monotypic Penicillus Kumar et Hameed, 1993 and P. indicus be rejected as legitimate taxa and that the record of P. indicus be considered a unique report of a Pennella sp. infecting several species of sharks.
Specimens of the parasitic siphonostomatoid copepod Caligus tenuifurcatus Wilson, 1937 were collected from the oral cavity of the yellowfin snook, Centropomus robalito Jordan et Gilbert; the white snook, C. viridis Lockington (Perciformes, Centropomidae), and the yellow snapper, Lutjanus argentiventris (Peters) (Perciformes, Lutjanidae), from a Pacific coastal system of Mexico. Infection was most intense on C. viridis. Caligus tenuifurcatus can be distinguished from its closest congener, C. bonito Wilson, by the body proportions and the basal ornamentation of the medial setae of the second exopodal segment of leg 1. Taxonomic illustrations are provided of both female and male. This is the third record of C. tenuifurcatus; hitherto, it was known only as a parasite of the roosterfish Nematistius pectoralis Gill (Perciformes, Nematistiidae) from Panama and the Gulf of California. Hence, the finding of C. tenuifurcatus as a parasite of two species of centropomids and one species of lutjanid represents a significant expansion of the known host range of this copepod in the eastern tropical Pacific.
Two species of Lernanthropus de Blainville, 1822 parasitic on the sparid fish Pagrus pagrus L., 1758 and the sciaenid fish Umbrina canosai Berg, 1895, respectively, from the coastal zone of the State of Rio de Janeiro, Brazil, are redescribed and illustrated: L. caudatus Wilson, 1922, and L. leidyi Wilson, 1922. The male specimens of L. caudatus are described for the first time. There are new geographical and host records for these Lernanthropus species.
Background. Sea lice (Copepoda: Caligidae) are important pathogens in aquaculture, and because more fish species are being intensively cultured, more species of sea lice are recognized as pathogens. The aim of the present study was to gather baseline data regarding the effects of sea lice on a valuable sciaenid (Sciaenidae), the black drum, Pogonias cromis, by describing lesions associated with naturally occurring infections of Sciaenophilus tenuis van Beneden, 1855. Materials and Methods. Gross and histological examinations of copepods and lesions were made using light and scanning electron microscopy from samples collected from eight infected black drum captured in Mississippi Sound, northern Gulf of Mexico. Results. Adult females of S. tenuis were associated with a mucosal lesion on interopercula. Female copepods attached to folds of mucosa on the posterior half of interopercula with cephalothoraces directed anteriorly in parallel with the longitudinal axis of fish. All attached male copepods grasped the abdomen or genital complex of females and were not in contact with the host. Maxillipeds of female copepods were embedded in epithelium or subepithelial connective tissue and functioned as the primary attachment appendages. Epithelial hyperplasia, fibrosis of subepithelial connective tissue, and chronic inflammatory infiltrates including presumed eosinophilic granular cells surrounded maxillipeds, indicative of long-term, focal, parasite-host interaction. Conclusion. Aquaculture managers should regard S. tenuis as a potentially serious pathogen if fish develop intense S. tenuis infections associated with extensive gross lesions.
Freshwater bream Abramis brama inhabiting warm-water discharge canal of the „Dolna Odra" Power Plant (Poland) were surveyed within 1983-1986 for their copepod parasites Tracheliastes maculatus. A total of 812 bream was studied and 561 females and 7 males of the parasite were recovered. The overall prevalence (for the whole survey) was 23.3% and the overall abundance was 0.69. T. maculatus were prevalent and abundant in winter while in summer they were encountered sporadically. The seasonality of the parasite exhibited consistent pattern within the studied period and it showed no signs of rise beyond the natural balance limits.
This paper presents the first records of the parasitic copepod Caligus furcisetifer Redkar, Rangnekar et Murti, 1949 beyond Indian waters, specifically, on the body surface and head of the critically endangered largetooth sawfish (commonly referred to as the freshwater sawfish in Australia), Pristis microdon Latham, 1794 (Elasmobranchii, Pristidae), in brackish tidal waters of the Fitzroy River in the Kimberley region of Western Australia and the Leichhardt River in the Gulf of Carpentaria in northern Queensland. This represents a geographic range extension of ∼8000 km for this parasite. Further, it is only the second member of the genus Caligus to be found on an elasmobranch host in Western Australia and it is the first time this species has been reported from the Southern Hemisphere. Male biased dispersal of P. microdon may be the vector in which the parasite has dispersed from India across to northern Australia, or vice versa. A decline in populations of the critically endangered P. microdon (and possibly other pristid species) in these regions may lead to a concomitant decline in their parasite fauna.
During a parasitological survey of the reef ichthyofauna in the Caribbean coast of Mexico, parasitic siphonostomatoid copepods were obtained from the white grunt Haemulon plumierii (Lacepède) and the blue striped grunt H. sciurus (Shaw). Caligus haemulonis Krøyer, 1863 has been recorded from both species of Haemulon in the Northwestern Tropical Atlantic, but it is reported herein for the first time from Mexico. The prevalence and intensity of infection of C. haemulonis has not previously been evaluated in the Caribbean grunts; during this survey, prevalence was highest in H. sciurus; values are similar to those found in other haemulids. Lernanthropus chacchi sp. nov. can be distinguished from its closest congener, L. rathbuni Wilson, 1922, by its female having a dorsal plate covering the entire urosome and the lack of lateral notches at the base of the modified third legs, the male has relatively longer third legs, different body proportions and ornamentation of the first and second legs. This is the third species of Lernanthropus known from reef grunts in the Caribbean and the second species of the genus described from Mexican waters. The infection prevalence of the new species on H. sciurus (24%) was higher than that known for L. rathbuni from other haemulids. Taxonomic illustrations of females and males of both species are also provided. Other crustacean ectoparasites included the copepod Hatschekia spp. and praniza larvae of a gnathid isopod.
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