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Horseshoe crab

Limulus polyphemus


There were many empty shells of these crabs on the beach. These crabs, which can become quite large, live in shallow ocean waters on soft sandy or muddy bottoms. They occasionally come on shore to mate. Behind their legs, they have book gills, which exchange respiratory gases and are also occasionally used for swimming, which is usually done upside down. A true endoskeleton is absent, but the body has an endoskeletal structure with cartilaginous plates that support the book gills.


Huntington Beach State Park

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Maria dB
Maria dB 9 years ago

Zoonerd - wanted to let you know that your comment led me to learn more and encouraged me to write a blog about the horseshoe crabs - thank you!

Maria dB
Maria dB 9 years ago

Thanks for pointing that out, ZooNerd. I just read about it and had no idea that their blood was harvested. This article states that the harvesting may be threatening the populations of crabs.

ZooNerd 9 years ago

Did you know that a lot of our medicine comes with horseshoe crab blood. So we are in debt to these ancient creatures. They are older then the Dinosaurs. I love these creatures. Nice shot.

Maria dB
Spotted by
Maria dB

South Carolina, USA

Spotted on Jan 19, 2015
Submitted on Feb 1, 2015

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