Guinot, 1976
Carapace moderately wide. Dorsal surface distinctly areolated in prominent areas, entirely covered by tubercles very coalescent and forming a paving, facetted, petaloid (a large raised central granule surrounded by a crown of conical granules), and perforated, with many pores on their circumferences. Front with two lobes separated by a distinct median notch. Spinose tubercles on the antero-lateral and frontal borders. Sternal plastron nearly smooth in front of the sternite 4, elsewhere with facetted tubercles, small but numerous; the same tubercles on the male abdomen. Male chelipeds with the black colouration on the fixed finger not extending onto the palm. The same ornamentation of petaloid tubercles on the outer surface of carpus and palm, becoming spiniform on the margins. On the ambulatory legs, numerous same tubercles, which show a more spinose appearance on the margins, more noticeably on the propodus and dactylus. (Guinot 1998)
Type locality: Japan.
Range: Japan - (Guinot, 1976), Sagami Bay (Ortmann, 1893), Sagami Bay and Nagasaki (Balss, 1922c), Inubo-zaki (Yokoya, 1933), south-west of Goto-retto and Sagami Bay (Odhner, 1925), Nagasaki (Sakai, 1934a), Shimoda (Sakai, 1935), Tateyama Bay, Misaki, Shimoda and Nagasaki (Sakai, 1939), Hachijo-jima (Sakai, 1954), Ariake-kai (Miyake, 1961), Sagami Bay (Sakai, 1965b), from Boso Peninsula to Okinawa (Sakai, 1976a), Amakusa (Yamaguchi et al., 1976), Yamagata Prefecture (Suzuki S., 1979), Nanki Shirahama (Miyake, 1983), Yokohama, Tokyo Bay, off Hayama, Manazuru, Sagami Bay, Kii Nagashima, Kii Minabe, Kushimoto, Tosa Bay, Nagasaki, and Okinoerabu-jima (Muraoka, 1998); Korea - Keisho-nando and Ullung do (Kamita, 1941), Namhae Island (Kim, 1973), Cheju-do (Kim & Chang, 1985); East China Sea (Takeda & Miyake, 1968c).