Redescripiton of Ligidium japonicum Verhoeff, 1918 based on the type material (Crustacea, Isopoda, Ligiidae)

Abstract

Ligidium japonicum Verhoeff, 1918 is redescribed based on the type specimens in Verhoeff’s collection. The species is redefined on the basis of uropodal endopod that is 1.1 － 1.3 longer than exopod, pleopod 1 exopod with long setae, and pleopod 2 endopod with U-shaped apex, as well as presence of denticles on pleopod 2 endopod inner margin and one beak-shaped dent on outer margin at anterior position than cutout of inner margin. Variation in morphological characters is shown between type material and samples collected from Chiba prefecture.