EXPLORE > ANIMALS > INVERTEBRATES
Limulus polyphemus
Horseshoe crabs are found in the fossil record as far back as 300 million years. They are not true crabs but more closely related to scorpions and spiders.
As the name implies, the crab has a curved U-shaped carapace (shell) reminiscent of a horseshoe which protects the entire body. The crab has several sets (and types) of eyes on both the top and bottom of its body. The legs, gills and mouth are all located on the underside of the body where they are protected by the carapace.
These crabs will move between ecosystems depending on the stage of their lifecycle. Females will lay their eggs on sandy beaches during the spring and summer, and the newly hatched offspring will quickly migrate into tidal flats or the sandy ocean floor where there are more food sources and better protection from predators. Adult crabs will venture into the deeper ocean to feed, then return to the beaches to breed.
Although they are eaten or used for other purposes around the world, there is not a major fishery for the horseshoe crab.
Range and Habitat
Limulus polyphemus is the North American species of horseshoe crab. It is found along Atlantic and Gulf of Mexico coasts, primarily on sandy beaches and ocean bottoms. Additional species of horseshoe crab are found in the Indian Ocean and the western Pacific Ocean.
Conservation Status
Common. However, human development of beaches, ocean acidification, warming seas and pollution all threaten this species status. In some parts of the United States, especially where the crab is considered a keystone species, they cannot be harvested.
Limulus polyphemus
Horseshoe crabs are found in the fossil record as far back as 300 million years. They are not true crabs but more closely related to scorpions and spiders.
As the name implies, the crab has a curved U-shaped carapace (shell) reminiscent of a horseshoe which protects the entire body. The crab has several sets (and types) of eyes on both the top and bottom of its body. The legs, gills and mouth are all located on the underside of the body where they are protected by the carapace.
These crabs will move between ecosystems depending on the stage of their lifecycle. Females will lay their eggs on sandy beaches during the spring and summer, and the newly hatched offspring will quickly migrate into tidal flats or the sandy ocean floor where there are more food sources and better protection from predators. Adult crabs will venture into the deeper ocean to feed, then return to the beaches to breed.
Although they are eaten or used for other purposes around the world, there is not a major fishery for the horseshoe crab.
Range and Habitat
Limulus polyphemus is the North American species of horseshoe crab. It is found along Atlantic and Gulf of Mexico coasts, primarily on sandy beaches and ocean bottoms. Additional species of horseshoe crab are found in the Indian Ocean and the western Pacific Ocean.
Conservation Status
Common. However, human development of beaches, ocean acidification, warming seas and pollution all threaten this species status. In some parts of the United States, especially where the crab is considered a keystone species, they cannot be harvested.