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

Abstract

Three new species of free-living marine nematodes, belonging to three genera, Epacanthion Wieser, 1953, Enoplolaimus De Man, 1893 (both family Enoplidae Dujardin, 1845), and Oncholaimus Dujardin, 1845 (family Oncholaimidae Filipjev, 1916), are described from northern Japan. Epacanthion quadridiscus sp. nov. is most similar to Epacanthion enoploidiforme (Gerlach, 1953), E. gorgonocephalum Warwick, 1970, and E. georgei Inglis, 1971 in spicule length and the absence of a precloacal supplement, but differs from them in the shape of the gubernaculum and the arrangement of the subcephalic and cervical setae in the male. Enoplolaimus longigubernaculum sp. nov. differs from all of its congeners in having a long and straight gubernaculum. Oncholaimus secundicollis sp. nov. is distinguished from all of its congeners by the presence of a precloacal papilla, postcloacal papilla, and tail papilla in the male.