A New Species of Chromadorina (Nematoda : Chromadoridae) Discovered in a Laboratory Aquarium

Abstract

A species of marine nematode, Chromadorina hiromii sp. nov., is de- scribed based on cultured specimens found in an aquarium containing medusae and polyps of Aurelia aurita (Linnaeus, 1758). The native habitat of the species is unknown, but certainly somewhere on the Pacific coast of Cen- tral Japan. Chromadorina hiromii resembles C. cervix (Wieser, 1951) and C. bergensis (Allgen, 1932) but differs from them in having a robust gubernacu- lum with well-cuticularized lateral pieces and five or six precloacal supple- ments in the male. Chromadorina hiromii is the second species of the genus known from Japan, the first being C. inversa Wieser, 1955, which was de- scribed from a single female collected at Shirahama. An examination of topotypic male specimens of C. inversa is required to understand its rela- tionship to C. hiromii.