Merostomata
From Wikipedia, the free encyclopedia
 |
||||||||
|---|---|---|---|---|---|---|---|---|
 |
||||||||
| Scientific classification | ||||||||
|
||||||||
|
|
||||||||
|
Merostomata is a class of marine Chelicerata which includes horseshoe crabs and eurypterids. It includes only four living species but dozens of fossil species mainly from the Paleozoic. The class Merostomata is slowly being abandoned in favour of splitting it into two classes, Xiphosura and Eurypterida. This is because Merostomata is thought to be paraphyletic, with the Eurypterida more closely related to the Arachnida, forming the group Cryptopneustida (Boudreaux, 1979). Inertia, however, has prevented this change from being incorporated in textbooks, which continue to use the traditional "Merostomata".
The Merostomata are the only chelicerates to possess compound eyes; the arachnids have lost the ancestral arthropods' fully developed latero-anterior compound eyes.
[edit] References
- Boudreaux H. B., 1979. Arthropod phylogeny with special reference to insects. John Willey & sons, New York, Chichester, Brisbane, Toronto. 320 pp.
