Scutumara enodis, a new genus and species of grapsid crab (Decapoda: Grapsidae) from Okinawa, Ryukyus, Japan

A new genus and species of coral reef grapsid crab, Scutumara enodis, is described from Okinawa, Ryukyus, Japan. The new genus is allied to Pseudograpsus H. Milne Edwards, 1837, but differs in having the carapace longer than broad, the dorsal surfaces smooth and glabrous without distinct regions, the epigastric cristae weak or absent and the front well produced. Additionally, the fingers do not form a gape when closed. Two other species, Pseudograpsus laniger Tesch, 1918, and Pseudograpsus miyakei Nakamura & Takeda, 1972, are also tentatively referred to the genus Scutumara.