Two species of philometrid nematodes (Philometridae) from marine fishes off Japan, including Philometroides branchiostegi sp. n. from Branchiostegus japonicus (Malacanthidae)

Abstract

Nematodes of the family Philometridae Baylis et Daubney, 1926 include a large number of species parasitic in the body cavity and various body tissues of fishes (Moravec 2006). to date, 26 species of these parasites have been reported from marine and freshwater fishes in Japanese waters, including representatives of the genera Clavinema Yamaguti, 1935, Philometra costa, 1845 and Philometroides Yamaguti, 1935(ishii 1916a,b, 1931, Yamaguti 1935, 1941, 1961, Fujita 1940, Machida 1970, Moravec and Nagasawa 1989, Moravec et al. 1998, 2002, Nagasawa 2008, Quiazon et al. 2008a. However, it can be expected that the Japanese fauna of philometrids, particularly of those parasitizing marine fishes, is still little known and most species have not yet been discovered.During recent investigations into the parasites of some marine fishes from the Sea of Japan, off the coast of Japan, gravid female specimens of philometrid nematodes were collected from the yellow goby Acanthogobius flavimanus (temminck et schlegel), Pterogobius elapoides (günther) and Pterogobius zonoleucus Jordan et snyder (all gobiidae, Perciformes), and from the horsehead tilefish Branchiostegus japonicus (Houttuyn) (Malacanthidae, Perciformes). Taxonomic evaluation of this nematode material is presented in this paper.Acanthogobius flavimanus (maximum size 30 cm) is a commercial temperate marine, brackish and freshwater fish occurring mainly along the shore of bays and estuaries, distributed in Japan, Korea and siberia. two other gobiids, P. elapoides (maximum size 8.3 cm) and P. zonoleucus (maximum size 6.7 cm), are small temperate marine fishes occurring near rocky shores, distributed in the Northwest Pacific (P. elapoides from central Japan and Korea to Hong Kong, P. zonoleucus in Japan and the Korean Peninsula). Branchiostegus japonicus (maximum size 46 cm) is a commercial tropical marine fish, distributed in the western Pacific from central Honshu to the south china sea, also reported as far south as the Arafura sea (Froese and Pauly 2011). Materials and MethodsFour specimens of Pterogobius elapoides were sampled during scUBA diving in the southern sea of Japan, off sekumi (35°33′N, 135°50′E) 3 school of Marine science and technology, tokai University, 3-20-1 orido, shimizu, shizuoka 424-8610, Japan abstract: Gravid females of two species of philometrid nematodes (Philometridae) were collected from marine perciform fishes in Japanese waters, mainly from the southern Sea of Japan. Based on light microscopy and scanning electron microscopy examinations, the previously described but poorly known species Philometra cryptocentri Yamaguti, 1961 is redescribed from specimens recovered from the abdominal cavity of Acanthogobius flavimanus (temminck et schlegel), Pterogobius elapoides (günther) and P. zonoleucus Jordan et Snyder (all Gobiidae) (all new host records); the number (14) and arrangement of cephalic papillae in this species are described for the first time. The new species, Philometroides branchiostegi sp. n. from head tissues of Branchiostegus japo...

Occurrence of new Philometra sp. in mangrove red snapper Lutjanus argentimaculatus from the Karachi coast, Pakistan

“…The body length is smaller than that of the gravid of P. carolinensis (Moravec et al, 2006) and larger than that of the gravid specimen of P. kiddakoi (Moravec et al, 2019) and gravid specimen of P. cryptocentri (Moravec et al, 2012). It is thinner when compared with the sub-gravid P. kiddakoi (Moravec et al, 2019), and the gravid specimen of P. cryptocentri (Moravec et al, 2012).…”

“…The present specimen is recovered from the gonad of host Lutjanus argentimaculatus (Forsskal, 1775) from Karachi coast, Pakistan. Other type species recorded are Philometra kidakoi (Moravec et al, 2019), from the ovary of Gymnothorax kidako (Temminck & Schlegel), reported in Japan; Philometra cryptocentri (Yamaguti, 1961) redescribed by Moravec et al (2012), from specimens recovered from the abdominal cavity of Acanthogobius flavimanus (Temminck & Schlegel), Pterogobius elapoides (Günther). Reported from the Southern Sea of Japan.…”

New records of philometrids (Nematoda: Philometridae) from marine fishes off Japan, including description of Philometra kidakoi sp. n. and Congerinema japonicum gen. et sp. n.

“…Knowledge of the fauna of philometrid nematodes (Philometridae) parasitising marine fishes in Japanese waters remains fragmentary. To date, a total of 20 nominal species of these parasites, belonging to the genera Clavinema Yamaguti, 1935 (1 species), Philometra Costa, 1845 (17 species) and Philometroides Yamaguti, 1935 (2 species), have been reported from marine representatives of the fish orders Perciformes, Pleuronectiformes, Scorpaeniformes, Siluriformes and Tetraodontiformes from off Japan (Ishii 1931, Yamaguti 1935, 1941, 1961, Machida 1970, Moravec and Nagasawa 1989, Moravec et al 1998, 2012a, 2018, Quiazon et al 2008a; see Nagasawa 2008 for the other literature).…”

Rhabdochona angusticaudata sp. n. (Nematoda: Rhabdochonidae) from the Japanese eel Anguilla japonica, and new records of some other nematodes from inland fishes in Japan

“…In the period from 1984-2009, samples of nematodes from Japanese fishes from Honshu, Shikoku and Hokkaido were collected by the Japanese co-author of the present study. A part of this material (nematodes from marine fishes) has already been evaluated in previous publications (Moravec et al 2010(Moravec et al , 2012a. Results of the morphological-taxonomical evaluation of nematodes recovered from Japanese inland fishes are presented here.…”