Diversity and Distribution of Mangrove Associated Crabs (Infraorder: Brachyura) of India and the Relationship Between Mangroves and Crabs

India's long coastline harbours an extensive mangrove cover, supporting rich biodiversity. Brachyuran crabs constitute one of the most diverse invertebrate groups in the mangrove ecosystem. In the present study, we have compiled a checklist of 184 brachyuran crabs belonging to 99 genera and 29 families, reported to date from mangroves of India. Mangroves on the East coast of India host 127 species, those on the West coast 83 species, and those on the Islands 54 species. The crabs of mangrove ecosystem form 20% of all the brachyuran crabs reported from various other habitats of India. Two species of crabs, Nanosesarma sarii Naderloo and Turkay 2009 and Neosarmatium malabaricum (Henderson, 1893) were recorded for the first time during field surveys conducted in the mangroves of Maharashtra. The crab species richness of different coastal states of India showed a positive correlation with mangrove species richness (R = 0.63, R2 = 0.40, p = 0.03) and with mangrove cover (R = 0.73, R-2 = 0.53, p = 0.01). The present study revealed a high diversity of brachyuran crabs associated with Indian mangroves and also the findings emphasize the importance of mangroves for their existence.