FAO Species Identification Guide for Fishery Purposes Western

1150 Crabs
Gecarcoidea lalandii (H. Milne Edwards, 1837)
Frequent synonyms / misidentifications: Hylaeocarcinus humei Wood Mason, 1873; Pelocarcinus
marchei A. Milne Edwards, 1890; P. cailloti A. Milne Edwards, 1890; Limnocarcinus intermedius De Man,
1879 / None.
FAO name: En - Purple land crab.
Diagnostic characters: Carapace distinctly transversely ovate, swollen, surfaces smooth; orbits relatively
small, eyes slanted obliquely in adults; third maxilliped without any flagellum on exopod. Colour: purplish
brown to purple and reddish purple.
Size: Maximum carapace width 13 cm (males).
Habitat, biology, and fisheries: Fully terrestrial, can be found many kilometres away from the sea. Normally
inhabits shallow burrows or under trees and rocks in undisturbed forests in isolated islands, where they may be
very common. The crabs release their larvae into the sea, which return to land upon completion of their
development. Gecarcoidea lalandii is only occasionally collected for food, much the same as Cardisoma
carnifex. Caught by hand or traps throughout their range, and sold live. Its market value, however, is
comparatively low.
Distribution: Throughout Indo-West Pacific.
Remarks: Another species of the genus occurs in the area, G. natalis (Pocock, 1898), known only from
Christmas and Cocos-Keeling islands. The 2 species are easily distinguished by their coloration: G. lalandii
is purple whereas G. natalis is bright red.