Horseshoe Crab --- Arthropods

Limulus polyphemus

Million of year ago, the oceans were filled with many different types of horseshoe crabs. Today there are only 5 species left. Limulus polyphemus live at the edge of the ocean, along the Atlantic coast from Canada to the Gulf of Mexico. It is the only horseshoe crab in the Atlantic Ocean. The others live off the coast of Asia.

The horseshoe crab has a thick body shell shaped like a horseshoe like a horseshoe. It also has a long tail that trails behind it. From below you can see 5 pair of legs ending in little claws. It is called the horseshoe crab because it has a general body shape similar to the crab. But it isn’t crab at all! In fact, it’s more closely related to scorpions and spiders.

The animal usually stays in the sand on beaches. There, it uses its legs to bury itself. It finds its food--- molluscs and worms--- in the sand. When it has to move, its long tail works like a lever to help push it out of the sand. The tail also helps it put itself back on its legs when it has been turned over by a large wave. In the water, the horseshoe crab swims easily on its back.

When it’s time to lay their eggs, males and females cross the sand to get to the highest part of the beach. The female digs a hole and lays up to 10,000 eggs. The eggs hatch in about 2 weeks and young horseshoe crabs reach the sea with the help of the rising tide.

PHYLUM: Joint-legged animals

ORDER: Horseshoe crabs

FAMILY: Living horseshoe crabs

LENGTH: up to 24 inches

DIET: molluscs, worms, and algae

NUMBER OF EGGS: up to 10,000

HOME: Atlantic Ocean off east coast of North America.