Three New Species of Free-living Marine Nematodes (Nematoda: Enoplida) from Northern Japan

Abstract

Three new species of firee-Iiving marine nematedes, belonging to three genera, Epacanthion Wieser, 1953, EnQplolaimus De Man, 1893 (both family Enoplidae Dujardin, 1845), and Oncholatmus Dujardin, 1845 (family Oncholaimidae Filiptev, 1916), are described from northern Japan. Eipacanthion quadridiscus sp, nov, is most similar to Elpacanthion enoploidijbrme (Gerlach, 1953), E, gorgonocephalum Warwick, 1970, and E. geongei Inglis, 1971 in spicule length and the absenee of a precloacal supplement, but diifers from them tn the shape of the gubernaculum and the arrangement of the subcephalic and cervical setae in the male. Enoplolaimus longigubernaculum sp. nov. differs from alI of its congeners in having a long and straight gubernaculum. Oncholaimus secundicoglis sp. nov.

<i>Oncholaimus langhovdensis</i> sp. nov. (Nematoda: Enoplea: Oncholaimida), a New Species of Free-living Marine Nematode from Langhovde, Dronning Maud Land, East Antarctica

“…According to previous studies (Filipjev 1918;Steiner 1921;Ditlevsen 1928;Cobb 1930;Kreis 1932Kreis , 1934Allgén 1935;Gerlach 1958;Allgén 1959;Wieser 1959;Chit- Filipjev 1968;Vitiello 1970;Belogurov et al 1975a, b;Coles 1977;Belogurov and Belogurova 1978;Tsalolikhin 1979;Belogurov and Fadeeva 1980a, b;Smolyanko and Belogurov 1987;Pavlyuk 1991;Smolyanko and Belogurov 1991;Pastor de Ward 1993;Platonova and Kulangieva 1995;Huang and Zhang 2006;Leduc 2008;Shimada et al 2009;Chen and Guo 2014) (Ditlevsen 1930), and the other four species should be transferred to Metoncholaimus Filipjev, 1918 based on the presence of gubernacula (Ditlevsen 1928;Gerlach 1956Gerlach , 1957Allgén 1959) Oncholaimus langhovdensis sp. nov. closely resembles 11 of them based on the conico-cylindrical tails present in males and amphid (posterior half of buccal cavity) and excretory pore positions (2-3 times the buccal cavity length from the anterior body end), the short spicules (1.1-1.3 times abd and 30-40% of the tail length), and Demanian system present in females.…”

<i>Zalonema sesokoensis</i> n. sp. (Nematoda: Desmodoridae), a new nematode species from subtidal sediments of Sesoko Island, Japan

“…Zalonema has not yet been recorded from the coast of Japan. Knowledge of the taxonomy of free-living marine nematodes in Japanese waters remains limited, with less than 100 species recorded from the region so far (Yoshikawa 1992;Shimada et al 2009;2012;Shimada 2014;Shimada and Kajihara 2014;Shimada and Kakui 2015;2019;2020;Leduc and Sinniger 2018). Here, I describe Zalonema sesoskoensis n. sp.…”

The First Record of a Species of Clausiidae (Copepoda: Cyclopoida) from Japanese Waters, with the Proposal of a New Genus

“…(e.g. Shimomura and Mawatari 2001;Kajihara 2002;Shimada et al 2009;Kakui et al 2012;Yamasaki et al 2012;Yoshihara et al 2012). This might indicate that a diversity of habitats in good condition exists in Oshoro Bay, and further field surveys investigating the richness of the marine and coastal fauna are required in this area.…”