Two New Species of Munnogonium (Isopoda : Asellota : Paramunnidae) from Japan

Abstract

Two new species of Munnogonium are described from Japan as the first record of this genus from the Western Pacific. Munnogonium armigerum sp. nov. is distinguished from the most similar species, M. adensis Miiller, 1991, by its anterior four pereonites armed with some acute teeth laterally, though the two species share the uniramous uropod and the distomesially projected article 3 of antenna 2. Munnogonium orientale, sp. nov. shows similar sexual dimorphism to that of M. maltinii (Schiecke and Fresi, 1972) : the article 3 of antenna 2 is twice as broad in males as in females. The present new species differs from all its congeners in having a short anterodorsal projection of the head, pleopod 1 with a pair of long, broad, lateral projections, and male coxal plates 1-4 with one spine each.