New species and new records of pinnotherid crabs (Crustacea: Decapoda: Brachyura) from the Yellow Sea

Five species belonging to two genera of pinnotherid crabs are reported from the Yellow Sea. Two are new to science, namely: Sakaina glabra sp. nov. and Sakaina granulata sp. nov.; while three species are recorded for the first time from China: Pinnaxodes major Ortmann, 1894, Pinnaxodes mutuensis Sakai, 1939, and Sakaina japonica Serène, 1964. Sakaina glabra can be easily distinguished from congeners by lacking a thick rim of pubescence along the anterolateral margin of the carapace. Sakaina granulata closely resembles S. asiatica ( Sakai, 1933), but differs mainly in having a row of granule-like denticles along the anterolateral margin of its carapace.