A New Record of Cavernicolous Crab Sesarmoides boholano Ng, 2002 (Brachyura, Sesarmidae) from Ishigaki Island, Southern Ryukyu Islands, Japan

Abstract. Sesarmoides boholano is newly recorded from Ishigaki Island, the southern Ryukyu Islands, Japan. The specimens from Ishigaki Island tend to have larger body size and more slender ambulatory legs than those from topotypic specimens. However the differences of these populations are not very significant, Ishigaki population is regarded as S. boholano. This study records a second distributional area of the species and substantially extends the range north from the Bohol, the Philippines. Key words: Sesarmoides boholano Ng, 2002, cavernicolous crabs, taxonomy, new to Japan, Ryukyu Islands