Shen, 1932
Diagnosis: Dactylus of third maxilliped small, attached on basal third of propodus and extended not beyond its extremity. Ambulatory legs hairy, second pair longest. Sixth segment of male abdomen with its lateral margins convex, and folded internally.
Description of female: Carapace anteriorly subquadrilateral, posteriorly suborbicular, a little broader than long. Surface convex, pitted. Regions not defined.
Front deflexed and produced slightly beyond orbit. Its anterior margin almost truncate from its dorsal aspect, but triangular from its anterior, its middle angle longer and larger than lateral.
Orbit small and rounded. Antennulae obliquely placed in deep fossae under front. Antennae small, each situated between antennula and orbital hiatus.
Epistome short, depressed. Anterior margin of buccal cavity triangularly projected between palpi of third maxillipeds.
Third maxillipeds oblique, ischium and merus fused, its outer margin broadly rounded, inner distal angle strong. Palpus large, propodus broadened basally and tapering distally, dactylus attached on basal third of inner margin of propodus and extended not beyond extremity of the former. Propodus and dactylus both bearing long bristle hairs.
Cheliped stout and pubescent. Merus with its margins rounded. Carpus longer than broad from its dorsal aspect. Palm longer than high, its distal portion slightly broader than basal, inner and outer surfaces slightly convex, margins rounded. Fingers nearly horizontal. Movable finger broader and slightly longer than immovable, the former bearing a large tooth at its base, its tip hooked, and the latter bearing a very small one near its middle, its tip nearly straight.
Ambulatory legs thick, somewhat flattened and hairy. Second pair longest. First shorter than third. Fourth shortest. Margins of merus subparallel and those of distal three segments each bearing long and fine hairs, especially those of second and third legs. Carpi of second and third each with an oblique line of hairs on its dorsal surface. Propodus smoothly ridged and hairy on its anterior margin. Dactylus shorter than propodus, strongly curved and sharply pointed.
Abdomen elongate oval. First two segments nearly covering whole surface of sternum between fourth pair of legs. Third segment as long as first two segments taken together, its basal margin narrower than distal. Fourth, fifth and sixth similar in shape but their breadth gradually becoming narrower and the curvature of their distal margins stronger. Seventh with its basal margin convex, distal broadly rounded.
Description of male: Carapace harder. Postfrontal region somewhat depressed. Abdomen with its first segment partly covered by carapace. Second very short, its median length greater than its lateral. Third largest, its basal margin broader than distal and lateral convex. Fourth, fifth and sixth tapering distally. Lateral margins of fourth concave, of fifth straight and of sixth convex medially and slightly constricted distally and folded internally, distal margin of sixth segment concave medially. Seventh broader than long, its distal margin broadly rounded. First pair of male abdominal appendages tapering distally and hairy laterally.
Sexual variations: Male carapace smaller and stronger than female, postfrontal region somewhat depressed. Female abdomen sometimes as narrow as that of male, narrowing regularly from first segment to seventh, its sixth segment folded as in male (not so in normal female abdomen), its first and second segments each bearing a pair of small biramous pleopods. (Shen, 1932: 145)
Type locality: Hsingtsun, Shandong Peninsula, China.
Range: China - Shandong Peninsula (Shen, 1932), southern coast of Shandong Peninsula (Shen, 1937).