Scylla serrata and Scylla tranquebarica are the common mud crabs occurring in the estuarine and mangrove areas along the East coast of India. Scylla serrata is commonly called as “red crab” and it prefers to live in low saline waters, whereas S. tranquebarica, the “green crab” lives in high saline waters. Male crabs of S. serrata grow to 700 to 800 gm at the maximum, whereas S. tranquebarica grows up to 3 kg. The export size of the crab is 500 g and above for males and 250 g and above for females.