Pistosauroidea

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Pistosauroidea
Temporal range: Early Triassic - Late Cretaceous
Augustasaurus BW.jpg
Life restoration of Augustasaurus hagdorni
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Sauropterygia
Clade: Eosauropterygia
Clade: Pistosauroidea
Baur, 1887-90
Subgroups

Pistosauroidea is a group of marine reptiles within the superorder Sauropterygia that first appeared in the latter part of the Early Triassic and were the ancestors of plesiosaurs. Pistosauroids are rare in Triassic marine assemblages, and are represented by only a few fossils from central Europe, the United States, and China.[1] Recent phylogenetic analyses consider the Triassic pistosauroids to be a paraphyletic grouping, meaning that they do not form a true clade. Plesiosauria is now placed within Pistosauroidea, while the traditional pistosauroids are successively more basal, or primitive, sauropterygians.[2]

Below is a cladogram of pistosauroid relationships from Cheng et al. (2006):[1]

Sauropterygia 

Placodontia




Pachypleurosauria



Nothosauria


 Pistosauroidea 

Corosaurus



Cymatosaurus




Pistosaurus




Yunguisaurus




Augustasaurus



Plesiosauria








Below is a cladogram of pistosauroid relationships from Ketchum & Benson, 2011:[3]

Pistosauroidea 

Cymatosaurus


 Pistosauria 

"Pistosaurus postcranium"




Bobosaurus



Pistosaurus



Yunguisaurus




Augustasaurus



Plesiosauria






References[edit]

  1. ^ a b Cheng, Y.-N.; Sato, T.; Wu, X.-C.; Li, C. (2006). "First complete pistosauroid from the Triassic of China" (PDF). Journal of Vertebrate Paleontology. 26 (2): 501–503. doi:10.1671/0272-4634(2006)26[501:fcpftt]2.0.co;2. 
  2. ^ Rieppel, O.; Sander, P.M.; Storrs, G.W. (2002). "The skull of the pistosaur Augustasaurus from the Middle Triassic of northwestern Nevada" (PDF). Journal of Vertebrate Paleontology. 22 (3): 577–592. doi:10.1671/0272-4634(2002)022[0577:tsotpa]2.0.co;2. 
  3. ^ Hilary F. Ketchum and Roger B. J. Benson (2011). "A new pliosaurid (Sauropterygia, Plesiosauria) from the Oxford Clay Formation (Middle Jurassic, Callovian) of England: evidence for a gracile, longirostrine grade of Early-Middle Jurassic pliosaurids". Special Papers in Palaeontology. 86: 109–129. doi:10.1111/j.1475-4983.2011.01083.x.