Rostrum a low blunt angle of anterior margin of carapace. Eyes triangular, overreaching rostrum with their full length. Antennal spine absent, antennal angle inconspicuous and blunt. Peduncles of antennula and of antenna of about same length.
Third maxilliped with merus and ischium considerably widened, forming an operculum; the last three segments narrow, about twice as long as wide. Large chela of adult male with a distinct concavity in the anterior margin above the base of the fixed finger; in females and young males this concavity is absent or insignificant. Carpus about as long as palm and about as long as high. Merus of adult males with a distinct rounded, forwards produced lobe in basal half of lower margin, upper margin of merus serrate; in females and young males the lobe is much smaller, more triangular, upper margin of merus smooth or indistinctly serrate.
Telson longer than wide at base, quadrangular in outline, narrowing slightly posteriorly; posterolateral angles rounded. A small denticle present in the middle of the posterior margin, otherwisetelson unarmed. Endopod of uropod broadly quadrangular with rounded corners, slightly longer than telson.
Type locality of C. subterranea japonica: " Japan, Tokiobai"; holotype female, in MZS, preserved in alcohol, condition very poor.
Type locality of C. harmandi: "Japon" ; syntypes ( 1 male, 3 females) in MP, no. Th 80, in alcohol, condition mediocre.
Type locality of C. californiensis japonica (and C. c. bouvieri, which is its replacement name): "Japon"; holotype female in MP, no. Th 70, in alcohol, condition rather good.
Western Pacific region: S.E. Siberia, Korea, N. China and Japan. Also found in fossil state in Japan.
Habitat and Biology:
On intertidal mud flats in protected habitats. The animal makes its burrows in the soft substrate.
Total body length 1.2 to 6 cm, rarely 7 cm. Ovigerous females with a body length of 2.5 to at least 5 cm.
Interest to Fisheries:
Supposedly this species, like most other Callianassa listed here, is used as bait for fishing. The only mention of its economic importance known to me is that by Liu (1955: 63, pl. 23 figs 1-5) who included the species (under the name Callianassa harmandi) in his " Economic Shrimps and Prawns of North China".