Two New Species of Parhyale (Crustacea : Amphipoda : Hyalidae) from Southeastern Japan and the Philippines

抄録

Parhyale hachijoensis sp. nov., from the Izu Islands of Japan, is characterized by the following features : in maxilla 1 the palp is 2-articulate with the articulation near the middle of the palp ; in gnathopod 1 one of the palmar corner spines on the propodus is displaced to the posterior margin ; in pereopods 6 and 7 the posterior margins of the propodi are lined with 4 and 3 groups of spines, respectively ; in uropod 1 the peduncle has an ordinary distolateral spine ; and in uropod 3 the inner ramus is vestigial and fused to the peduncle. Parhyale philippinensis sp. nov., from two sites in the Philippines, is characterized by the following features : in maxilla 1 the palp is 1-articulate with a constriction slightly beyond the middle of the palp ; in gnathopod 1 the palmar corner spines of the propodus are close together ; in pereopods 6 and 7 the posterior margins of the propodi are lined with 5 groups of spines ; in uropod 1 the peduncle has an elongate distolateral spine ; and in uropod 3 the inner ramus is fully articulated. The fact that both new species have the propodal posterior margins lined with a number of groups of spines in pereopods 6 and 7 suggests that they belong to the P. hawaiensis complex.