Dvinosauria

Dvinosaurs are one of several new clades of Temnospondyl amphibians named in the phylogenetic review of the group by Yates and Warren 2000. They represent a group of primitive semi-aquatic to completely aquatic amphibians, and are known from the Late Carboniferous to the Early Triassic, being most common in the Permian period. Their distinguishing characteristics are a reduction of the otic notch; the loss of a flange on the rear side of the pterygoid; and 28 or more presacral vertebrae.

Not to be confused with Dinosaur.

Dvinosauria
Temporal range: Late Carboniferous - Early Triassic, 279.5–251.3 Ma
Dvinosaurus primus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Order: †Temnospondyli
Suborder: †Dvinosauria
Yates and Warren, 2000
Subgroups

Trimerorhachidae is the most basal family of dvinosaurs. Most other dvinosaurs are placed in the superfamily Dvinosauroidea. Within Dvinosauroidea are two families, Eobrachyopidae and Tupilakosauridae, as well as dvinosaurs that cannot be placed in either family, such as Dvinosaurus and Kourerpeton. A 2008 phylogenetic analysis found Eobrachyopidae to be paraphyletic, representing a grade of basal dvinosauroids. Below is a cladogram showing the phylogenetic relationships of dvinosaurs from Englehorn et al. (2008):[1]

Dvinosauria 
 Trimerorhachidae 
 

Trimerorhachis

 
 

Neldasaurus

 
 
 
 

Perryella

 
 Dvinosauroidea 
 

Isodectes (Eobrachyopidae)

 
 
 

Acroplous (Eobrachyopidae)

 
 
 

Dvinosauridae

 
 

Kourerpetidae

 
 Tupilakosauridae 
 

Slaugenhopia

 
 

Tupilakosaurus

 
 

Thabanchuia

 
 
 
 
 
 
 

References
  1. Englehorn, J.; Small, B.J.; Huttenlocker, A. (2008). "A redescription of Acroplous vorax (Temnospondyli: Dvinosauria) based on new specimens from the Early Permian of Nebraska and Kansas, U.S.A.". Journal of Vertebrate Paleontology. 28 (2): 291–305. doi:10.1671/0272-4634(2008)28[291:AROAVT]2.0.CO;2.


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.