Carapace in adult males strongly swollen. Frontal horns flat, their inner margins forming with anterior margin of carapace a shallowly concave arc. Carpus of first leg without anterodorsal spine. Propodus of first pereiopod of male with anterodorsal spine. Abdominal somites with a single distinct transverse groove. Colour a pink or reddish marbled with white; abdominal somites irregularly marbled. Legs ringed with whitish and pink.
Type locality: (for P. v. inflata and P. v. mauritanicus)" sur toute la côte mauritanienne, du cap Barbas [ = Cabo Barbas, western Sahara, 22°18'N, 46°41 ' W) jusque un peu au nord de Saint-Louis [Sénégal, 16°01'N, 16°30'W], par des fonds de 20 m à 50 m et souvent sur le sable coquillier". Syntypes in MP, no longer extant (not located in 1989).
Type locality of P. thomsoni: "58 mls. W 1\2 N of Blackball Head [S.W. Ireland], 51°20'N., 11°30'W., 212- 229 fms [ = 388-420 m), sand" Holotype male in NMI, no. 104.1916, in good condition in alcohol.
Eastern Atlantic from W. of Ireland (53°N) to southern Senegal (14° N), also in the western Mediterranean, West of about 16°E, not in the Adriatic.
Habitat and Biology:
Depth range from 180 to 600 m. In the westernMediterranean mostly between 400 and 500 m. On rocky and coral substrates, as well as on mud. At times gregarious. Trawl hauls of 200 to 500 specimens have been recorded off N W. Africa.
Maximum total body length 50 cm; a single record of a specimen of 75 cm needs confirmation. Usually the body length ranges between 20 and 40 cm.
Interest to Fisheries:
The main commercial fishery of the species is off N.W. Africa. At its inception, this fishery was mainly operating by trawls, especially after 1954. From 1958 onwards, however, the lobster-pot fishery gradually replaced trawling. In the western Mediterranean, the commercial importance of the species is not very high, but it is regularly taken by deep sea trawlers as a bycatch. It is brought to the markets in Spain and Italy, but it is far from frequent there. Sold mostly fresh, sometimes frozen. Catch statistics are not recorded for this species. However, the figures given for Palinurus spp in the FAO Yearbook of Fishery Statistics most probably correspond to mixed catches of P. elephas and P. mauritanicus (4921 metric tons in 1987 and 7869 tons in 1988).