Horseshoe Crabs

Horseshoe crab belongs to a class called Merostomata, living fossils, or those organisms that haven’t changed in millennia.

Horseshoe Crabs
Table of Contents

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 spawns 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

Q1: What are Arthropods?

These are invertebrates with jointed legs. They make up about 75% of all animals on Earth and have a major role in maintaining ecosystems as pollinators, recyclers of nutrients, scavengers and food for other animals. 

Source: The blue-blooded sea creature on Odisha’s coastline

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