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Horseshoe crab

Limulus polyphemus


The horseshoe crab has the appearance of a prehistoric creature. It has been around for over 300 million years. They are completely harmless and serve great economic importance to our medical society. The blood of the horseshoe crab is copper based instead of iron based like human blood. Scientists discovered that horseshoe blood will gel when it comes in contact with bacteria. As a result, the biomedical companies have developed a way to extract the agent from their blood. They use this to test injectable medication for gram negative bacteria. So thank the horseshoe crab the next time you get your flu shot.


They live on the sandy ocean floor in the Atlantic Ocean and the Gulf of Mexico. They do migrate to the beaches in May and June to lay their eggs on the beach.

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1 Comment

Interesting spotting michelle.rhodes.9619,nice info,thanks for sharing and welcome to Project Noah.
I hope you like the community as much we do,you can also explore many other features,like the chats for questions and comments on your's and other's spottings and to elp you in the ID process.
there are also a blog, wich link is in the base of the page,there you can find many interesting articles and news writen by our better specialists in the several fields.
Enjoy yourself,see you arround :)

Maryland, USA

Spotted on Sep 18, 2011
Submitted on Oct 25, 2012

Spotted for Mission

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