de Haan, 1841
The carapace is subcircular and discoidal, the upper surface being quite smooth and somewhat depressed, the branchio-cardiac grooves alone are fairly distinct. The front is produced beyond the general outline of the carapace and its anterior edge is almost straight, having a shallow median groove. The hepatic facets are distinct, in rear of which the marginal rim of the carapace is beaded with microscopical granules. The anterior boundary of the buccal cavern and also the anterior extremities of the pterygostomial regions are produced beyond the edge of the front. Below the eyes, the edge of the pterygostomial region is deeply cleft.
Chelipeds of the adult male are very long, they are about 2.5 times the length of the carapace. The arm is slightly depressed and its upper basal surface and also the anterior border are covered with distant granules. The wrist smooth, the palm flattish and distally broadened, its inner border is finely milled. The fingers are very thin and broad and are elegantly curved, the cutting edge of the movable finger is entire and fringed with hairs, that of the immovable finger also entire but with no hair. The ambulatory legs are very slender and smooth.
The abdomen of male consists of three pieces; the first and seventh terga are freely movable, while the second tergum is very short and movable only at each side, its median part being fused with the third tergum. The suture line between the fifth and sixth terga is distinct but not movable. The abdomen of female is as in Philyra syndactyla. (Sakai, 1937)
Type locality: Japan.
Range: Mozambique - Delagoa Bay (Barnard, 1947, 1950); South Africa - Zululand (Barnard, 1947, 1950); Pakistan - Karachi (Alcock, 1896, Tirmizi & Kazmi, 1991); Andaman Islands (Alcock, 1896); Mergui Archipelago (Alcock, 1896); Japan - (de Haan, 1841), Shimoda, Nanki Shirahama and Nagasaki (Sakai, 1937a), Amakusa, Sea of Ariake, Tsuyazaki, Tottori, and Toyama (Miyake et al., 1962), Sagami Bay (Sakai, 1965b), Sagami Bay, Kii Nagashima, Kii Minabe, and Nagasaki (Sakai, 1976a), Shiono-misaki (Takeda, 1979a), off Kochi (Miyake, 1983), Oshima Passage, Amami-Oshima (Takeda, 1989); Taiwan - Tingch'ieting (Lin, 1949); Hong Kong (Stimpson, 1907); Gulf of Tongking (Zarenkov, 1990); Philippines; Australia - South Australian coast (Miers, 1886), Cockburn Sound (Tyndale-Biscoe & George, 1962); New Caledonia (A. Milne Edwards, 1874); 35-150 m.