Rhabdochona (Rhabdochona) keralaensis sp. nov. (Rhabdochonidae) and some other nematodes in the Indian mottled eel Anguilla bengalensis bengalensis from India

Abstract

A new species of parasitic nematode, Rhabdochona (Rhabdochona) keralaensis sp. nov., is described based on specimens recovered from the intestine of Anguilla bengalensis bengalensis (Gray) collected from the freshwater bodies of Kerala State, southern India. It is characterized mainly by the presence of ten anterior prostomal teeth, absence of basal teeth, simple deirids, length of spicules, number and arrangement of preanal papillae and non-filamented eggs. Two species of camallanid nematodes, adults of Camallanus cotti Fujita, 1927 and a single Procamallanus (Spirocamallanus) sp. fourth-stage larva, were also recorded from A. bengalensis. Camallanus cotti, a pathogenic parasite of many species of wild and aquarium-reared fishes in many countries of South and East Asia, Europe, South and North America, West Indies and Australia, is reported for the first time from a representative of the fish family Anguillidae. Descriptions of R. (R.) keralaensis and Indian specimens of C. cotti, based on light and scanning electron microscopical examinations, are provided. Camallanus oxygasterae Gupta et Bakshi, 1983 is considered a junior synonym of C. cotti.

Indian Mottled Freshwater Eel, Anguilla bengalensis Bengalensis (Gray, 1831), A Threatened Species of Indian Subcontinent- A Review

“…In the Ganges river, West Bengal for example, A. bengalensis specimens that were caught contained methyl mercury concentrations that were higher than the limits set by the PFA (Provention of Food Adulteration Act) for human consumption [16]. A new species of parasitic nematode was found in the intestines of A. bengalensis collected from the freshwater bodies of Kerala state in southern Indian in 2012 [17]. Climate change play a role in fluctuations of abundance in anguillid speciesparticularly larval transport and glass eel recruitment are very limited.…”

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

“…The non-bifurcated deirids with rounded distal tips, the character of anterior prostomal teeth, absence of basal teeth, a slender female tail and non-filamented eggs of R. angusticaudata sp. n. are also found in two species of Rhabdochona that are specific parasites of freshwater eels: Rhabdochona anguillae Spaul, 1927 infecting A. anguilla in Europe and Rhabdochona keralaensis Moravec, Sheeba et Kumar, 2012 in Anguilla bengalensis (Gray) in India (Spaul 1927, Moravec et al 2012b). Of these, R. keralaensis markedly differs from the new species in the size of body (body length of male and female 12.5-17.1 and 22.3-27.8 mm, respectively, vs 8.4-13.6 mm and 19.1 mm), length of the left spicule (585-636 µm vs 300-384 µm), more numerous pairs of subventral preanal papillae (11-13 vs 9), presence (vs absence) of the bifurcated cuticular membrane forming a distinct dorsal outgrowth on the distal tip of the left spicule and a somewhat different arrangement of anterior prostomal teeth.…”

Observations on nematodes from the Indonesian shortfin eel Anguilla bicolor bicolor McClelland in India, including a revalidation of Heliconema ahiri Karve, 1941 (Physalopteridae)

“…b. bengalensis and A. b. bicolor. Results of the systematic evaluation of these parasites from A. bengalensis have been published by Moravec et al (2012b), wheras those from A. bicolor are presented herein.…”