Eriptychiida
Eriptychiida Temporal range: Late Ordovician, 450 Ma | |
---|---|
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | †Pteraspidomorphi |
Subclass: | †Heterostracomorphi |
Order: | †Eriptychiida |
Eriptychiida is an extinct marine taxon of vertebrate in the group Pteraspidomorphi.
The order contains only one genus, Eriptychius, and fossilized specimens from this genus have been found in North America. The group contains only two documented species: Eriptychius americanus and Eriptychius orvigi.
Characteristics
The structure of the dentine of eriptychiids is in many respects closer to that of heterostracans that to that of astraspids. This is the only argument to place them as the closest relatives to heterostracans, among the Ordovician vertebrates. However, eriptychiids differ from all other pteraspidomorphs in having a massively calcified endoskeleton, pervaded by canals for blood vessels.
See also
External links
This article is issued from Wikipedia - version of the Tuesday, April 26, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.