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.
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