Occurrence of a rare species of red crab, Ranina ranina (Linnaeus 1758)along Chennai coast

The red frog crab otherwise called spanner crab is a coastal water species and single representative of genus Ranina under family Raninidea. They prefer to inhabit in bare sandy areas of intertidal and coastal waters of more than 100m depth. Distribution of this crab is confined to tropical and sub topical coastal waters of Indian and Pacific oceans, from the coast of South Africa to Hawaii and the Great Barrier Reef. Occurrence of this species is very sparse in Indian waters and has been recorded once in Gulf of Mannar (Kasinathan et al., 2007).