Calappa calappa

Family
   Genus
Calappidae Dana,1852
Calappa

Species Name : Calappa calappa (Linnaeus, 1758)

Identification Key

Length of carapace rather less than half of its extreme width. Edge of clypeiform expansions entire and smooth. Carapace indistinctly tuberculated on anterior half but with wavy beaded lines towards the posterior surface.

Synonymy

Cancer calappa Linnaeus 1758, Syst. Nat. ed. Xii, I. P. 1048
Calappa fronicata

Fabricius 1793, Ent. Syst. Suppl, p. 345

Alcock 1896, J. Asiatic Soc. Bengal, vol. 65(2), p. 142

Calappa calappa

Borradaile 1903, Fauna, Geog. Maldive and Laccadive Archipel.p.436

Sakai 1976, Crabs of japan and Adjacent Seas, p. 129

Galil 1997, Resultats des Campagnes MUSORTOM, vol. 18, p.272




Habitat

Found on the bottoms of rock or broken shells; 10-50 meters deep.

Distribution

This species ranges widely in tropical Indo-Pacific from Zanzibar, Mauritius, Maldives, New Caledonia, New Guinea, Japan and Hawaii.

India

Lakshadweep islands, Andaman & Nicobar islands.

Description

Surface of Carapace nearly smooth anteriorly, marked with transverse wavy beaded lines posteriorly; its antero-lateral borders crenulated. Clypeiform expansions very large, their breadth equal to their edge smoothly moulded posterior border of the carapace. Outer part of the pterygostomian regions densely hairy. Front slightly projecting beyond the level of the orbits, bilobed, its breadth at the tip rather less than the breadth of the orbit. Transverse wing. like expansion near the distal end of the arm with its edge smooth and entire. Outer surface of palm with squamiform tubercles and transverse wavy beaded ridges. Upper margin or crest of palm bluntly dentate.

Remarks

There are two well known colour morphs occur in these crabs one in plain coloured and another spotted.