A new gastrotrich species of the genus Tetranchyroderma (Macrodasyida: Thaumastodematidae) from Korea

Abstract

Genus Tetranchyroderma is a representative marine gastrotrich genus with the dorsal cuticular armature of 3-5 pronged spines, which belongs to the family Thaumastodermatidae, the most diversified natural group of marine gastrotrichs. In Korea, twelve species have been reported in the genus Tetranchyroderma. As a serial study on the Korean gastrotrich fauna, a new Tetranchyroderma gastrotrichs species is described from shallow sublittoral sand bottom of a beach at Wando Island, south coast of Korea. Tetranchyroderma pinnatum sp. nov. is characterized by the cuticular armature with feathered triancres, two pairs of rod-like cephalic tentacles, a short testis and a large tube-shaped copulatory organ. This presentation deals with the morphological features of the new species based on detailed illustrations and SEM micrographs, together with systematic accounts on the affinities. A key to the species of genus Tetranchyroderma from Korea is also provided.rea, twelve species have been reported in the genus Tetranchyroderma. As a serial study on the Korean gastrotrich fauna, a new Tetranchyroderma gastrotrichs species is described from shallow sublittoral sand bottom of a beach at Wando Island, south coast of Korea. Tetranchyroderma pinnatum sp. nov. is characterized by the cuticular armature with feathered triancres, two pairs of rod-like cephalic tentacles, a short testis and a large tube-shaped copulatory organ. This presentation deals with the morphological features of the new species based on detailed illustrations and SEM micrographs, together with systematic accounts on the affinities. A key to the species of genus Tetranchyroderma from Korea is also provided.