Quick answer
Atlantic Horseshoe Crabs (Limulus polyphemus) are invertebrates found across North America. The ancient living fossil with blue blood. Adults typically weigh roughly 2 kg (4 lb), reach speeds of Slow; crawls and plows through sand, and live Often 20+ years. They feed on omnivore (worms, mollusks, algae, carrion) and are listed as Vulnerable on the IUCN Red List. Shallow coastal waters and beaches of the western Atlantic, along the eastern United States and the Gulf of Mexico.
Key takeaway
Atlantic Horseshoe Crabs (Limulus polyphemus) are invertebrates found across North America. The ancient living fossil with blue blood. Adults typically weigh roughly 2 kg (4 lb), reach speeds of Slow; crawls and plows through sand, and live Often 20+ years. They feed on omnivore (worms, mollusks, algae, carrion) and are listed as Vulnerable on the IUCN Red List. Shallow coastal waters and beaches of the western Atlantic, along the eastern United States and the Gulf of Mexico.
Atlantic Horseshoe Crab overview
Atlantic Horseshoe Crab (Limulus polyphemus) is an invertebrate listed here as Vulnerable. Typical weight about 2 kg; lifespan around Often 20+ years.
Atlantic Horseshoe Crab ecology
Diet: Omnivore (worms, mollusks, algae, carrion). Habitat: Shallow coastal waters and sandy beaches. Movement and social systems reflect those pressures across the native range.
Atlantic Horseshoe Crabs and people
Learn before you travel or keep related pets. Wild atlantic horseshoe crabs are not toys; captive care needs species-specific husbandry.
Status and further reading
Conservation label in our guides: Vulnerable. See the full Atlantic Horseshoe Crab profile for taxonomy, FAQs, and related topic guides on this site.
Range and habitat
Atlantic Horseshoe Crabs inhabit Shallow coastal waters and beaches of the western Atlantic, along the eastern United States and the Gulf of Mexico. Their preferred habitat includes shallow coastal waters and sandy beaches, where they find food, shelter, and breeding sites. Population density varies with prey availability, water access, and human disturbance. Protected areas and intact corridors remain essential for
Physical characteristics and behaviour
Adult atlantic horseshoe crabs typically measure about 0.6 m in length and weigh roughly 2 kg (4 lb). They can sprint at Slow; crawls and plows through sand when hunting or escaping predators. Atlantic Horseshoe Crabs are known for the ancient living fossil with blue blood — social structure, daily activity, and seasonal movements all reflect pressures in their native environment.
Sources
Atlantic Horseshoe Crab FAQs
What are key facts about atlantic horseshoe crabs?
Atlantic Horseshoe Crabs (Limulus polyphemus) are invertebrates found across North America. The ancient living fossil with blue blood. Adults typically weigh roughly 2 kg (4 lb), reach speeds of Slow; crawls and plows through sand, and live Often 20+ years. They feed on omnivore (worms, mollusks, algae, carrion) and are listed as Vulnerable on the IUCN Red List. Shallow coastal waters and beaches of the western Atlantic, along the eastern United States and the Gulf of Mexico.
What is the scientific name of the atlantic horseshoe crab?
Limulus polyphemus — used in research and conservation listings for atlantic horseshoe crabs.
What do atlantic horseshoe crabs eat?
Atlantic Horseshoe Crabs eat worms, mollusks, algae and carrion, with seasonal and regional variation in Shallow coastal waters and sandy beaches.
Where do atlantic horseshoe crabs live?
They are associated with Shallow coastal waters and sandy beaches. Local presence depends on food, cover, and human land use.
What is the conservation status of atlantic horseshoe crabs?
Listed in our guides as Vulnerable. Check the IUCN Red List and national assessments for the latest formal category.