Majid Crabs of the Arabian Sea

Abstract

The present study makes a part of the major and broad program undertaken to explore the decapod crustacean fauna of Pakistan coast. The work is basically of taxonomic nature. The Order Decapoda, of which about 8,000 species are known, contains the largest and probably the most familiar crustaceans (prawns and crabs) occurring along sea coasts of Pakistan. The decapod treated here are the true crabs belonging to Section Brachyura. This is the largest and most specialized group and contains more than a sixth of all crustacean species, the estimated number being 4,500. For present study majid crabs are selected for their strange behaviour, lack of systematic knowledge and also because they make an interesting group and form the second largest family of crabs over 600 species. Provenzano & Brownell extimate 900 species. In the account that follows, diagnostic features and introductions to Family Majidea is given, local species are illustrated and described. Notes on collection, preservation, natural history particularly masking and economic importance are also included. Full account of twenty-two species is prepared including synonymies, distribution, remarks and individual variation. Doubtful species were confirmed through correspondence with Dr.D.J.G. Griffin, director, Australian Museum, Sidney. Since it is not possible to give the account of all the species in the present report, full description of only three species is given; Schizophrys aspera, Simocarcinus simplex, and Doclea muricata. A schematic drawing for majidae is given for the terms used in the text. (Fig. 1 & 2). Carcinologist, like Gordon has directed attention to the importance of studying the abdominal appendages of male (Chopra, 1935) in view of their providing characters of considerable systematic values, as such special attention is paid to the study of these appendages. All the illustrations are original and completed in Indian ink, unless mentioned otherwise. Several specimen were kept under laboratory conditions and their behaviour was carefully noted. Phenomenon of masking in Camposcia retusa and Schizophrys aspera was observed and photographed.