Mangrove Horseshoe Crab

The mangrove horseshoe crab is found in tropical marine and brackish waters of India, Bangladesh, and Southeast Asia, and is the smallest of the four living horseshoe crab species, with females averaging 30.5 to 31.5 centimeters and males 28 to 30.5 centimeters long. Its tail is rounded in cross section rather than triangular, distinguishing it from other horseshoe crabs, and it lives close to the bottom of shallow, sandy or muddy brackish waters such as mangroves. Unlike other horseshoe crabs its flesh can contain lethal tetrodotoxin, and poisoning cases have occurred when it is mistaken for the harmless Tachypleus gigas and eaten as a delicacy. It is listed as Data Deficient on the IUCN Red List, though some regional populations such as in Hong Kong have declined sharply over the past decade.