Caseasauria

Caseasauria
Life picture of Cotylorhynchus
Temporal occurrence
Upper Carbon to Middle Perm
305 to 265 million years
Locations
Eurasia North America Eurasia
Systematics
Vertebrates (vertebrata) Meat finisher (Sarcopterygia) Land vertebrates (Tetrapoda) Amniotes (Amniota) Synapsids (Synapsida) Caseasauria
Scientific name
Caseasauria
Williston , 1912

The caseasauria are mainly from the early Permian known taxon of synapsids from the group of " pelycosaur ".

They divide into two different families, the small, insect- or carnivorous Eothyrididae and the large, herbivorous Caseidae .

The common features of the Caseasauria are the enlarged nostrils (nares) and a pointed snout, which is formed by the intermaxillary bone. The skull is wide, the temporomandibular joint was low on the head. The teeth of the Caseidae were uniform (homodont) and blunt, the Eothyrididae had two enlarged canine-like teeth in the upper jaw.

The Caseasauria lived from the Upper Carboniferous to the Middle Permian. While the Eothyrididae are only known from the Upper Carboniferous / Lower Permian from North America , remains of the Caseidae have also been found in Eurasia ; this group is documented up to the Upper Permian and probably died out in the mass extinction at the end of this epoch.

The Caseasauria systematically form the basal representatives of the synapsids and form the sister group of the Eupelycosauria , from which the therapsids ("mammal-like reptiles") and finally the mammals have developed. The following cladogram illustrates this:

Synapsida	Caseasauria    Eothyrididae   Eothyris     Oedaleops  Caseidae '  Eocasea     unwritten caseid from Bromacker     Oromycter     Casea     Ennatosaurus     Cotylorhynchus     Angelosaurus   Eupelycosauria   Varanopidae     Ophiacodontidae     Edaphosauridae   Sphenacodontia   Sphenacodontidae     Therapsida (including mammals )

literature

• TS Kemp: The Origin & Evolution of Mammals. Oxford University Press, Oxford 2005, ISBN 0-19-850761-5 .

Individual evidence

1. ↑ Maddin et al.: Cranial anatomy of "Ennatosaurus tecton" (Synapsida: Caseidae) from the middle permian of russia and the evolutionary relationships of Caseidae (PDF; 3.2 MB), 2008, p. 173.
2. ^ Reisz RR, Fröbisch J (2014) The Oldest Caseid Synapsid from the Late Pennsylvanian of Kansas, and the Evolution of Herbivory in Terrestrial Vertebrates. PLoS ONE 9 (4): e94518. doi: 10.1371 / journal.pone.0094518

Web links

• Caseasauria on Palaeos.com
• Caseasauria on Tolweb.org