A New Species of the Varunid Crab Genus Gopkittisak (Crustacea: Decapoda: Brachyura: Grapsoidea) from the Ryukyu Islands

抄録

A new species of the varunid crab genus Gopkittisak Naruse and Clark, 2009, G. angustum sp. nov., is described on the basis of seven specimens from intertidal sand flats at Iriomote Island, Ryukyu Islands, Japan. It is close to its sole congener G. gallardoi (Serene and Soh, 1976), but the different shapes of the carapace and male abdomen, as well as the setal pattern of the propodus of the fourth pereopod and the coloration in life, distinguish the new taxon from G. gallardoi.