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Horseshoe Crab

Limulidae

Horseshoe crabs are marine arthropods (family Limulidae) that live mainly in shallow coastal waters and estuaries on sandy or muddy bottoms, and they come ashore on beaches to spawn, often in large groups. Despite their name, they are not true crabs/crustaceans); they are chelicerates, more closely related to spiders and scorpions. They’re often called “living fossils” because their lineage can be traced in the geologic record to around 445 million years ago. Populations have declined in some regions due to habitat loss and harvesting pressures.

Horseshoe crabs are marine arthropods (family Limulidae) that live mainly in shallow coastal waters and estuaries on sandy or muddy bottoms, and they come ashore on beaches to spawn, often in large groups. Despite their name, they are not true crabs/crustaceans); they are chelicerates, more closely related to spiders and scorpions. They’re often called “living fossils” because their lineage can be traced in the geologic record to around 445 million years ago. Populations have declined in some regions due to habitat loss and harvesting pressures.