A New Land-hopper Genus, Nipponorchestia, with Two New Species from Japan (Crustacea, Amphipoda, Talitridae)

摘要

Nipponorchestia gen. nov. with two new species is described from terrestrial habitats in Japan. It is characterized by elongate antenna 1, 4-dentate lacinia on left mandible, maxilliped palp article 2 with mediodistal lobe, strongly subchelate gnathopod 1 in both sexes, cuspidactylate pereopods, moderately reduced pleopods, and marginally bare outer ramus of uropod 1. These features distinguish the new genus from allied genera: Bousfieldia Chou and Lee, 1996, Lanorchestia Miyamoto and Morino, 2010 and Paciforchestia Bousfield, 1982. Nipponorchestia curvatus sp. nov. occurs in coastal habitats and N. nudiramus sp. nov. in inland habitats; both species are separable by the shape of antenna 1.