(Heller, 1862)
Diagnosis:
Large spines of carapace broad and flattened, about as wide as long, much larger than the small spines. Sculpturation of abdomen wide, relatively few squamae, with extensive smooth area on anterior part of each somite. First and following abdominal somites with transverse row of squamiform sculpturation behind transverse groove.
Frontal horns almost equilaterally triangular, shorter and broader than in J. tristani. Squamiform sculpturation of the abdomen with the squamae narrower and more numerous than in J. tristani.
Type:
Type locality: "St. Paul", [ = St. Paul Island in the southern part of the Western Indian Ocean, at 38°44'S 77°30'E]. Syntypes in NMW.
Geographical Distribution:
The species is restricted to St. Paul and Amsterdam Islands in the southern Indian Ocean. A report of the catch of a single lobster in Kerguelen Islands by Aubert de la Rüe (1954:119) seems very reliable and is well documented (the specimen was brought up with algae entangled in the anchor of the ship "Lozère", a catch witnessed by A. Berland); but this evidently is a freak occurrence, as no lobster catches have been reported from the Kerguelen either before or after this event.
Habitat and Biology:
The species lives at depths between 0 and 60 m, on rocky or gravel bottom, being most numerous in the kelp zone between 10 and 35 m. Egg-laying starts in May, and ovigerous females have been observed until November, or exceptionally early December. Females are caught from May to October, while males dominate in most catches from November to April. The animals are nocturnal and feed on plants and (dead) animal matter.
Size:
The largest specimen ever recorded had a total body length of 37 cm. Males have been reported to attain total body lengths of 14 to 34 cm (carapace length 6 to 13 cm), and females, total body lengths of 9 to 24 cm (carapace lengths 4 to 9 cm). The average sizes are 21 to 28 cm (males), 19 to 21 cm (females). The specimes from Amsterdam Island on the average are slightly smaller than those from St. Paul Island.
Interest to Fisheries:
The fishing grounds are restricted to the islands of St. Paul and Amsterdam, the shorelines of which are respectively 12 and 27 km long, and the area in which the species can be fished is less than 1 km wide. Early visitors of the then uninhabited islands caught the lobsters by hand in very shallow water. In the crater lake of St. Paul, which is a bay opening to the sea, the lobsters could be brought to the hot springs in the crater bottom without taking them out of the water, and cooked there. In 1928, a rather large fishing enterprise was started with lobster pots. The settlement on St. Paul consisted of a canning factory and the houses for the fishermen and employees of the factory, about 120 people in all. In 1931, the project was abandoned because of health conditions (a beri-beri epidemic). Later attempts (1938-1939, 1948-1949, 1949-1950) with factory ships were also unsuccessful. In 1950, a new French factory ship, the SAPMER, equipped with deepfreeze installations, operated near the islands. The lobsters were headed, washed and frozen on board. Six "campagnes" were carried out between 1950 and 1956, each providing between 214 and 255 tons of lobster tails (the equivalent of 5000 tons of whole lobsters) Fear for overfishing made that several protective measures have been suggested.