Eusuchia

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Eusuchia
Temporal range: Early Cretaceous - Recent, 130–0Ma
Three species of living eusuchian: Gharial (left), American Alligator (center), and American Crocodile (right).
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Crocodylomorpha
Clade: Neosuchia
Clade: Eusuchia
Huxley, 1875

The Eusuchia ("true crocodiles") are a clade of crocodylomorphs that first appears in the Early Cretaceous with Hylaeochampsa.[1] All living crocodilian species are eusuchians, as are many extinct forms.

Description[edit]

Unlike primitive crocodylomorphs, crocodyliforms have secondary bony palates. This feature enables living crocodylians to safely breathe in through their nostrils while the rest of the head (including the mouth) remains submerged. This structure reaches its greatest elaboration among eusuchians, in which the internal nares are completely surrounded by the pterygoid bones.

Phylogeny[edit]

Cladogram after Holliday and Gardner, 2012:[2]

Eusuchia

Isisfordia




Hylaeochampsa




Aegyptosuchidae


Crocodylia

Borealosuchus



Gavialoidea



Brevirostres (alligators, crocodiles and relatives)






Below is a cladogram after Puértolas, Canudo and Cruzado-Caballero, 2011:[3]

Eusuchia

Isisfordia




Hylaeochampsa


Crocodylia


Borealosuchus



Gavialoidea





Allodaposuchus




Pristichampsus



Brevirostres (alligators, crocodiles and relatives)







References[edit]

  1. ^ Benton, Michael J.; Sibbick, John (2000). Vertebrate Palaeontology. Blackwell Publishing. p. 233. ISBN 0-632-05614-2. 
  2. ^ Casey M. Holliday and Nicholas M. Gardner (2012). "A New Eusuchian Crocodyliform with Novel Cranial Integument and Its Significance for the Origin and Evolution of Crocodylia". PLoS ONE 7 (1): e30471. doi:10.1371/journal.pone.0030471. PMC 3269432. PMID 22303441. 
  3. ^ Eduardo Puértolas, José I. Canudo and Penélope Cruzado-Caballero (2011). "A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids". PLoS ONE 6 (6): e20011. doi:10.1371/journal.pone.0020011.