0 a type of sea creature with a hard rounded shell shaped like a horseshoe or the letter U, five pairs of legs, and a long tail:
Environmentalists say more must be done to protect horseshoe crabs because they provide vital food for migratory shorebirds.
The horseshoe crab uses its ice-pick-like tail to steer in the water and to right itself should it be overturned in the sand.
Prehistoric trilobites looked similar to horseshoe crabs.
