Merostomata

Horseshoe crabs

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IUCN Red List Status: NOT EVALUATED external link Showing: scientific names

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Merostomata

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Limulus-polyphemus
Limulus polyphemus Linnaeus, 1758
Limulus polyphemus Linnaeus, 1758
Tachypleus gigas
Tachypleus tridentatus (Leach, 1819)
Tachypleus tridentatus (Leach, 1819)
Tachypleus tridentatus (Leach, 1819)
Limulus polyphemus
Limulus polyphemus

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Table of Contents

General Description

GeneralDescription

Source and Additional Information
Supplier
Animal Diversity Web external link
Copyright
©1995-2008, The Regents of the University of Michigan and its licensors. Some rights reserved external link
Author
Phil Myers, Museum of Zoology, University of Michigan
Source URL
View original data object external link
Citation
Myers, P. 2001. "Merostomata" (On-line), Animal Diversity Web. Accessed October 25, 2009 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Merostomata.html. 

   

(horseshoe crabs, eurypterids) The Merostomata includes two rather different groups of marine organisms, the eurypterids and the horseshoe crabs. Eurypterids are now extinct; they lived 200 to 500 million years ago. Some were huge, reaching a length of 3 m. Their morphology suggests that they fed on a variety of kinds of foods. Some may have been amphibious, emerging onto land for at least part of their life cycle. The horseshoe crabs are an ancient group, but only 5 species exist today. They feed on small invertebrates. Horseshoe crabs are often used as laboratory animals by physiologists.

 

Members of this class have a large shield that covers the cephalothorax. The compound eyes are reduced. The second pair of appendages, the pedipalps, resemble walking legs. They have a long, spike-like appendage called a telson that projects from the rear of their bodies. Respiration is via book gills.

 
 

Source:

 

Hickman, C.P. and L. S. Roberts. 1994. Animal Diversity. Wm. C. Brown, Dubuque, IA.

 

Brusca, R. C., and G. J. Brusca. Invertebrates. 1990. Sinauer Associates, Sunderland, MA.

 
"Merostomata". Encyclopedia of Life, available from "http://www.eol.org/pages/1919". Accessed 21 Mar 2010.