(Von Siebold, 1824)
Diagnosis:
Submarginal posterior groove of carapace as wide medially as laterally. Epistomal ridges feebly granulated, with an acute well developed anterior tooth. No pleopods on 1st abdominal segment of female. Chitinous margin of male genital aperture toothed throughout its length.
Type:
Type locality: Japan, possibly neighbourhood of Nagasaki; restricted to Omura Bay near Nagasaki, Kyushu, Japan, by Holthuis(1966: 265-266). Lectotype in RMNH, no. D 5611 (dry, condition good, paralectotypes in RMNH, BM, USNM).
Geographical Distribution:
Indo-West Pacific region: Japan, Korea, China, Taiwan, Philippines, eastern and western Australia.
Habitat and Biology:
The species has been reported from depths between 30 and 318 m. The substrate on which it is caught is described as sand or mud, sometimes with shells; some older records indicate rocky environments.
Size:
Maximum total length 47 cm; carapace length 8 to 18 cm.
Interest to Fisheries:
Already H. Burger around 1830, said that the species is scarce in Japan, but when caught, is used as food (Holthuis, 1966: 266). Also in Korea and China the species is sold on the markets as food, but is nowhere plentiful. Chang (1964: 11) remarked that it is very scarce in Taiwan and on the markets it is priced cheaper than the other spiny lobsters because of its coarseflesh and thick shell. Motoh and Kuronuma (1980: 56) reported that in the Philippines the species" is rarely offered for sale in the market", and that it is caught there by commercial trawlers. George (1983: 17) remarked that in Western Australia, off Port Hedland, Linuparus trigonus was trawled with deepwater Engel trawls in 200m of water "in sufficient quantities to provide occasional excellent meals for the crew and that in Japan this same species is the basis for a small commercial enterprise". Off Townsville, Queensland, Australia, the species "occurs in densities high enough to support an occasional fishery. The fishery is confined to a small, well-defined area of the continental slope, about 70 km by 20 km, in depths of 200 to 250 m. Here L. trigonus is taken mainly by prawn trawlers during their off-season" (T.J. Ward, in press).