Horseshoe crab

About Horseshoe crab:

• It belongs to a class called Merostomata, living fossils, or those organisms that haven’t changed in millennia. 
• It is a marine chelicerate arthropod. The Chelicerata is a division within the Arthropoda, containing animals such as spiders, scorpions, harvestmen, mites and ticks. 
• Like all arthropods, they have a segmented body and segmented limbs and a thick chitinous cuticle called an exoskeleton.
• Habitat: They are living in shallow coastal waters on soft sandy or muddy bottoms and spawn mostly on intertidal beaches at summer-spring high tides. 
• There are four extant horseshoe crab species:

• The American horseshoe crab (Limulus polyphemus) along the eastern coast of the USA and in the Gulf of Mexico,
• The tri-spine horseshoe crab (Tachypleus tridentatus),
• The coastal horseshoe crab (Tachypleus gigas) 
• The mangrove horseshoe crab (Carcinoscorpius rotundicauda) 

• The last three are Indo-Pacific species found mainly in the coastal waters of India, Southeast Asia, China and Japan.    
• In India, Odisha is the largest habitat of horseshoe crabs. 
• Conservation status in India

• Wildlife Protection Act 1972: Schedule IV

• IUCN Status

• American horseshoe crab: Vulnerable
• Tri-spine horseshoe crab: Endangered
• The two other species are not listed yet