Two New Species of Philometrid Nematodes (Philometridae), Barracudia Notabilis n. sp. and Philometra Consimilis n. sp., from the Ovary of the Hound Needlefish Tylosurus Crocodilus (Belonidae) Off Florida, USA.

Two new species of philometrid nematodes (Philometridae), Barracudia notabilis n. sp. and Philometra consimilis n. sp., are described from males found in the ovary of the hound needlefish Tylosurus crocodilus (Péron et Lesueur) (Belonidae) from off the Atlantic coast of Florida, USA. Both species are described and illustrated based on light and scanning electron microscopical examinations. Barracudia notabilis n. sp., the first representative of this genus from fishes in the Atlantic Ocean, can be differentiated from other congeners by the body length of the male (2.69 mm), the length of the gubernaculum (57 µm) and spicules (81 µm), and by the shape of the gubernaculum. Philometra consimilis n. sp. differs from all congeners mainly in the unique structure of the distal tip of the gubernaculum (bearing two smooth dorsal barbs) and the species is also characterized by the length of spicules (111 µm) and the length of the gubernaculum (84 µm). Further studies are needed to discover and describe so far unknown gravid females of Barracudia spp.

Heliconema Monopteri n. Sp. (Nematoda: Physalopteridae) from Monopterus Cuchia (Hamilton) (Osteichthyes: Synbranchidae) in India, with Notes on the Taxonomy of Heliconema Spp.

A new nematode species, Heliconema monopteri n. sp. (Physalopteridae), is described from the stomach and intestine of the freshwater fish Monopterus cuchia (Hamilton) (Synbranchidae) in Bijnor district, Uttar Pradesh, India. It is mainly characterized by the lengths of spicules (468 - 510 µm and 186 - 225 µm), the postequatorial vulva without elevated lips, the presence of pseudolabial lateroterminal depressions and by the number and arrangement of caudal papillae. This is the first representative of the genus reported from a synbranchiform fish. Another new congeneric species, Heliconema pisodonophidis n. sp. is established based on a re-examination of nematodes previously reported as H. longissimum (Ortlepp, 1922) from Pisodonophis boro (Hamilton) (Ophichthidae) in Thailand; ovoviviparity in this species is a unique feature among all physalopterids. Heliconema hamiltonii Bilqees et Khanum, 1970 is designated as a species dubia and the nematodes previously reported as H. longissimum from Mastacembelus armatus (Lacépède) in India are considered to belong to H. kherai Gupta et Duggal, 1989. A key to species of Heliconema Travassos, 1919 is provided.

The philometrid nematode Philometroides acreanensis n. sp. from the stomach wall of the catfish Pimelodus blochii in north-western Brazil.

A new nematode species, Philometroides acreanensis n. sp. (Philometridae), is described from female specimens recovered from the stomach wall of the freshwater catfish Pimelodus blochii Valenciennes (Pimelodidae) collected in the Acre River (Amazon River basin), Acre State, Brazil. Based on examination by light and scanning electron microscopy, the new species differs from the two other South American congeneric species mainly in the body length of the gravid female (240-280 mm), the length of the oesophagus (1.25 mm in holotype) representing 0.5% of the entire body length, the range of cuticular embossment, as well as the location in the host (stomach), order of the fish host (Siluriformes) and the geographical distribution (Amazon River drainage system). This is the third known species of Philometroides Yamaguti, 1935 reported from South America. A key to species of Philometroides occurring in the fish of America is provided.

Dentirumai philippinensis n. gen., n. sp. (Nematoda: Philometridae), a new tissue-infecting philometrid nematode from the loach goby Rhyacichthys aspro (Valenciennes) (Rhyacichthyidae) in the Philippines.

A new genus and species of the philometrid nematode Dentirumai philippinensis n. gen., n. sp. Philometrinae, Philometridae, are described on the basis of the female specimens found in the loach goby, Rhyacichthys aspro (Valenciennes), from the upper Bianuan River, Municipality of Casiguran, Aurora Province, in the Philippine Archipelago. Dentirumai philippinensis was collected from the body cavity, subcutaneous tissues near the bases of the pectoral and pelvic fins, and surrounding body tissues in the hypaxial musculature of R. aspro. Based on light microscopic and scanning electron microscopic examination, the new nematode species is morphologically close to the genus Rumai Travassos, 1960 except for one major difference, i.e. the presence of a sclerotized ring in the oral aperture armed with distinct numerous minute teeth on its inner surface. This important taxonomic feature makes it possible to erect a new genus, Dentirumai n. gen. to accommodate the newly discovered philometrid species. A key to genera of the Philometrinae is provided.

Seasonal development and pathological changes associated with the parasitic nematode Philometroides sanguineus in wild crucian carp Carassius carassius (L.) in England.

Pathological changes associated with the parasitic nematode Philometroides sanguineus (Rudolphi, 1819) are described for the first time from observations of infections in wild crucian carp Carassius carassius (L.) in England. The damage caused by P. sanguineus was influenced strongly by host size, parasite development and the seasonal migrations of female nematodes within host tissues. Male and unfertilized female nematodes located on the swim-bladder wall caused only minor, localized changes. In contrast, the migration of gravid female nematodes into the fins during autumn provoked an acute inflammatory response comprising neutrophils, eosinophils and lymphocytes. This was accompanied by fin distortion, swelling of the dorsal and caudal tissues, degenerative changes and localized oedema. The encapsulation of female nematodes in connective tissue throughout winter limited additional tissue damage. The emergence of gravid nematodes from the fins in spring to facilitate larval dispersal caused necrosis, hyperplasia and loss of skin integrity. This activity was again accompanied by acute inflammatory reactions. Pathological changes were more severe in crucian carp measuring less than 60 mm in length, with no signs of debilitation in larger fish. These observations suggest that any impact of P. sanguineus is strictly seasonal and may be limited to fry. Lesions caused by this parasite, only recently recorded in Britain, may represent an additional pressure upon wild crucian carp populations already threatened by hybridization, competition and habitat loss.

Philometra floridensis sp. n. (Nematoda: Philometridae) from the ovary of red drum Sciaenops ocellatus (Osteichthyes: Sciaenidae) off the coast of Florida, USA.

A new nematode species, Philometra floridensis sp. n. (Philometridae), is described from male and female specimens found in the ovary of red drum, Sciaenops ocellatus (Linnaeus) (Sciaenidae, Perciformes), from the Gulf of Mexico off Treasure Island, Florida, USA. Based on light and scanning electron microscopy examination, the new species differs from most other gonad-infecting Philometra spp. in having a smooth gubernaculum with a distinct dorsal tooth on the distal tip. The new species is most similar to P. carolinensis Moravec, de Buron & Roumillat, 2006, but differs in length and shape of spicules. It can be distinguished from P. carolinensis and other species with unknown males, by the markedly greater body length of gravid females (up to about 100 cm). Philometra floridensis is the third valid gonad-infecting species of Philometra reported from sciaenids.

[Description of a case of infection due to Dracunculoidea in French Polynesia]. / Un cas d'infection à Dracunculoidea en Polynésie française.

The purpose of this report is to describe a case of Dracunculoidea infection that led to acute arthritis of the knee in a young Polynesian. The implications of this first reported case of Dracunculoidea infection in French Polynesia are discussed.

Surface morphology of Nicolla skrjabini (Trematoda: Opecoelidae), a common parasite of European freshwater fishes, as revealed by SEM.

Scanning electron examination of trematode specimens belonging to Nicolla skrjabini (Iwanitzky 1928), collected from brown trout Salmo trutta fario L. in the Czech Republic, made it possible to study their surface morphology including details not described previously. The tegument bears numerous characteristic papillae mainly around and inside the suckers and around the genital pore and minute sensory organs near the anterior body end. Surface morphology may prove to be useful in distinguishing Nicolla spp.

Tissue-dwelling philometrid nematodes of the fish Arapaima gigas in Brazil.

The nematode Rumai rumai Travassos, 1960 (Philometridae) is redescribed from the tissues of the mouth, tongue, operculum and head of the arapaima, Arapaima gigas (Schinz) (Osteichthyes), from Mexiana Island, Amazon River Delta, Brazil. Additional data on the related Nilonema senticosum (Baylis, 1922) from the same host and locality are also presented. Rumai rumai is characterized by the presence of a sclerotized formation on the female cephalic end, dorsal and ventral cephalic projections, the shape and structure of the oesophagus and a conical caudal extremity. Males of both R. rumai and N. senticosum, specific parasites of the ancient arapaima fish in the Neotropics, remain unknown. The relationship between these tissue-dwelling nematodes and the aquaculture system of Mexiana Island is commented upon.

Nematode parasites of fishes: recent advances and problems of their research.

Although nematodes (Nematoda) belong to the most frequent and the most important parasites of fishes in the freshwater, brackish-water and marine environments throughout the world, the present knowledge of these parasites remains still incomplete, especially as to their biology and ecology, but also taxonomy, phylogeny, zoogeography, and the like. However, a certain progress in the research of fish nematodes has been achieved during recent years. An overview of some of the most important discoveries and results obtained is presented. As an example, existing problems in the taxonomy of these nematodes are shown in the dracunculoid family Philometridae (presently including 109 species in 9 genera), where they are associated mainly with some biological peculiarities of these mostly important tissue parasites. Nematodes of the Dracunculoidea as a whole remain poorly known; for example, of 139 valid species parasitizing fishes, 81 (58%) are known by females only and the males have not yet been described for members of 8 (27%) of genera. A taxonomic revision of this nematode group, based on detailed morphological, life history and molecular studies of individual species, is quite necessary; for the time being, Moravec (2006) has proposed a new classification system of dracunculoids, where, based on previous molecular studies, the Anguillicolidae is no longer listed in Dracunculoidea, but in an independent superfamily Anguillicoloidea. Important results have recently been achieved also in the taxonomy of fish nematodes belonging to other superfamilies, as well as in studies of their geographical distribution and diversity in different parts of the world and those of their biology. Opportunities for more detailed studies of fish nematodes have recently greatly improved with the use of some new methods, in particular SEM and DNA studies. There is a need to create a new classification system of these parasites reflecting phylogenetic relationships; a prerequisite for this is taxonomic revisions of different groups based on detailed studies of individual species, including mainly their morphology, biology and genetics. Further progress should concern studies on various aspects of biology, ecology and host-parasite relationships, because these data may have practical implications.

Anguillicola papernai (Nematoda: Anguillicolidae) and other helminths parasitizing the African longfin eel Anguilla mossambica.

The swim bladder nematode Anguillicola papernai Moravec & Taraschewski, 1988 has been investigated as regards its occurrence in longfin eels Anguilla mossambica (Peters) in rivers in South Africa. A. papernai revealed a prevalence of around 50% and a mean intensity of about 6 adult worms at 1 sampling site but were less abundant in 3 others. Field observations suggest a more narrow habitat preference than that of Anguillicola crassus and a seasonal pattern of abundance. African longfin eels harboured a poor helminth community. In addition to A. papernai, 2 gastro-intestinal nematodes occurred, the stomach worm Heliconema longissimum Ortlepp, 1923 as the dominant species, and the intestinal Paraquimperia africana Moravec, Boomker & Taraschewski, 2000. Experiments were undertaken using European eels Anguilla anguilla (Linnaeus) and copepods as laboratory hosts. The morphology of larvae and adult parasites obtained from these experimental hosts is described. The ultrastructure of adult worms recovered from wild longfin eels was studied. The 'papilla-like excrescences of fibrous structure' on the adult worms' cuticle, as mentioned in the original description, are in fact the attachment points of thick cords of fibers interconnecting the epicuticle with the hypodermis. Such a structure has not yet been described from any other species of Anguillicola Yamaguti, 1935. At present in South Africa, Mozambique and Madagascar attempts are on the way to establish an eel management like in Asia and Europe including eel farming. In this context, care should be taken to prevent the introduction of non-endemic eel parasites into Africa and Madagascar. On the other hand, the future commercial management of African eel species should not lead to the spread of A. papernai or other parasites of African eel species to Europe or elsewhere. In this study A. papernai has been experimentally demonstrated to be capable of reproducing in the European eel and of using European copepods as intermediate hosts.

Common sculpin Cottus gobio as a natural paratenic host of Proteocephalus longicollis (Cestoda: Proteocephalidae), a parasite of salmonids, in Europe.

Common sculpins Cottus gobio L. (Pisces: Cottidae), from the Mlýnský Brook near Ceské Zleby in the Sumava National Park, southwestern Bohemia, Czech Republic, were found to harbour in their intestines juvenile cestodes Proteocephalus longicollis (Zeder, 1800), a common parasite of holarctic salmonids, with a prevalence of 60% and intensity of 1 to 11 (mean 5) parasites per fish; undoubtedly, these prey fish serve as paratenic hosts. In this locality, the definitive host of P. longicollis is the brown trout Salmo trutta m. fario L., large specimens of which apparently acquire infection of this parasite by feeding on infected sculpins. C. gobio is the first known natural paratenic host of P. longicollis in Europe.

Amphibians and larvae of aquatic insects as new paratenic hosts of Anguillicola crassus (Nematoda: Dracunculoidea), a swimbladder parasite of eels.

Amphibians (tadpoles of the frog Bombina bombina [L.] and the newt Triturus vulgaris [L.]) and aquatic insects (larvae of the alderfly Sialis lutaria [L.] [Megaloptera], dragonflies Sympetrum sanguineum [Miller] and Coenagrion puella [L.] [Odonata], and the caddisfly Oligotrichia striati [L.] [Trichoptera]) were found to serve as paratenic hosts for the third-stage larvae (L3) of the nematode Anguillicola crassus Kuwahara, Niimi et Itagaki, 1974, a pathogenic swimbladder parasite of the eel Anguilla anguilla (L.) in Europe and elsewhere. This is the first evidence that, in addition to prey fishes and some aquatic snails, amphibians and aquatic insects can serve as paratenic hosts for this nematode parasite. A. crassus third-stage larvae were found, largely unencapsulated (encapsulated only in S. lutaria), mostly in the body cavity, on the gut surface and, less often, in the liver and in the subcutaneous tissue of legs in amphibians, and in the body cavity and on the gut surface in insect larvae; they could survive for at least 49 d in T. vulgaris and 69 d in S. lutaria. The capability of these larvae from S. lutaria (69 d post-infection) to infect the definitive host (eel) was confirmed by experimental infection of an eel.

Role of Leptodora kindti (Cladocera: Leptodoridae) in the life cycle of Raphidascaris biwakoensis (Nematoda: Anisakidae), a fish parasite in Lake Biwa, Japan.

Advanced third-stage larvae (body length 2.92 to 5.49 mm) of the fish nematode Raphidascaris biwakoensis Fujita, 1928 were found as frequent parasites of the leptodorid cladoceran Leptodora kindti (Focke) in Lake Biwa, southern Honshu, Japan, in July 1995. This is the first confirmed record of the L3 of this nematode species from an invertebrate host, showing that L. kindti may serve as a true intermediate host to R. biwakoensis, probably in addition to lower aquatic vertebrates. The high degree of prevalence of the nematode larvae in L. kindti in Lake Biwa indicates that this plankton crustacean is an important source of infection with R. biwakoensis for fish definitive and paratenic hosts.

Redescription and systematic status of Capillaria philippinensis, an intestinal parasite of human beings.

A redescription of the capillariid originally described as Capillaria philippinensis, a pathogenic intestinal parasite of humans, is provided on the basis of specimens collected in humans in the Philippines. The general morphology, particularly the structure of the male caudal end, shows that this species belongs to Paracapillaria Mendonça, 1963 according to the present classification system of capillariids; the species is transferred to Paracapillaria as Paracapillaria philippinensis (Chitwood, Velasquez, and Salazar, 1968) n. comb. Crossicapillaria n. subgen. is proposed to accommodate this species.

The amphipod Gammarus fossarum as a natural true intermediate host of the nematode Raphidascaris acus.

A single third-stage larva of the fish nematode Raphidascaris acus (Bloch, 1779) (body length 1.77 mm) was found in 1 of 775 gammarids Gammarus fossarum Koch examined from the Jihlava River, Czech Republic. This is the first confirmed record of the advanced L, of this species from an invertebrate host, showing that an invertebrate may serve as true intermediate host of this nematode, in addition to lower aquatic vertebrates. Until now, invertebrates have generally been considered as paratenic hosts of the second-stage larvae of R. acus.

Larval anisakid nematodes of Japanese common squid (Todarodes pacificus) from the Sea of Japan.

Two species of third-stage larvae of the family Anisakidae are described from the Japanese common squid (Todarodes pacificus Steenstrup) from the Sea of Japan. The larvae of 1 of them, Anisakis simplex (Rudolphi, 1809), commonly occur encapsulated in the viscera of squid, whereas those of another 1, identified as Lappetascaris sp., are found free in the mantle musculature. The latter, characterized by the presence of a very long ventricular appendix, a conspicuous esophageal gland, and the structure of the cephalic end (presence of sclerotized supports of lip anlagen), previously were reported by various authors as members of the genera Contracaecum, Thynnascaris, or Hysterothylacium. It appears that the larvae form the mantle of squid belong to a hitherto undescribed Lappetascaris species whose adults parasitize an, as yet unknown, predatory marine fish.

Trichospirura amphibiophila n. sp. (Nematoda: Rhabdochonidae) in the frog Eleutherodactylus martinicensis from La Désirade, French Antilles.

Trichospirura amphibiophila n. sp. (Nematoda) is described from the abdominal cavity (encapsulated near the liver) of the frog Eleutherodactylus martinicensis (Anura: Leptodactylidae) from the island of La Désirade in the French Antilles. It is characterized by the length of its spicules (459 microns and 90 microns) and their length ratio (1:5), by the presence of deirids and 7 pairs of caudal papillae in the male (2 preanal and 5 postanal), and by the site of localization (abdominal cavity) in the host. Trichospirura amphibiophila is the first known species of the genus parasitizing amphibians.

Brevimulticaecum sp. larvae (Nematoda: Anisakidae) from the frog Hyla minuta Peters in Trinidad.

Enscapsulated third-stage nematode larvae collected from the abdominal cavity of the Trinidadian hylid frog Hyla minuta are referred to the rare anisakid genus Brevimulticaecum. These are the first specimens of Brevimulticaecum from a tropical frog, and their presence may reflect the importance of amphibians as intermediate or paratenic hosts of reptilian parasites.