Four Species of Dulichiidae (Crustacea: Amphipoda) from Japan, with the Description of a New Genus and Two New Species

Abstract

Four species of the family Dulichiidae (Crustacea: Amphipoda) are described from Japan. Te frst species is Dulichia biarticulata Hirayama and Takeuchi, 1993, which is characterized by the 2-articulate accessory fagellum and the expanded basis of the pereopod 4. Te occurrence of this species from Miyagi–Osaka Prefectures and Fukui Prefecture is the frst record from localities other than the type locality, and the morphological characters of the female are also described for the frst time. Te second species, Dulichia latimana sp. nov., was collected from the Ariake Sea and Sagami Bay. In this species, the male has a robust gnathopod 2 with a short proximal projection on the propodus and the slightly expanded basis of the pereopod 4. Te third species is Dulichiopsis barnardi Laubitz, 1977 from of Fukushima Prefecture, which has the eyes composed of many dispersed ommatidia, the propodi of the pereopods 5–7 with a palm and the uropod 2 outer ramus about half length of the inner ramus. Te morphological characters of the male are frstly described. Te last species is Metadulichia kohtsukai gen. nov., sp. nov. from Sagami Bay. Tis species can be distinguished by the small maxilla 1 with 7 terminal robust setae on the outer plate, the maxilla 2 inner plate bearing single mediofacial seta, and the extremely short outer ramus of the uropod 2. A key to Japanese species of the family is provided.