Horseshoe crab

Definition

Marine arthropods belonging to the class Merostomata, known for their hard, domed carapace and long, spiked tail. Despite the name, they are more closely related to arachnids like spiders and scorpions than to true crabs.

Etymology

The term 'horseshoe crab' comes from the shape of their carapace, which is reminiscent of a horseshoe. The word 'crab' is used due to their superficial resemblance to true crabs.

Example

Horseshoe crabs are often found along the eastern coasts of North America and Asia, playing a crucial role in coastal ecosystems.

Related Terms

• Limulus
• Arthropod
• Carapace
• Chelicerae
• Merostomata

Usage Notes

Horseshoe crabs are often studied for their blue blood, which contains a unique substance called Limulus Amebocyte Lysate used in medical applications to detect bacterial endotoxins.