Sphenacodontoidea

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Sphenacodontoids
Temporal range: Late Carboniferous-Recent, 303.4–0Ma
Ctenospondylus2DB2.jpg
Ctenospondylus
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Sphenacodontia
Clade: Sphenacodontoidea

Sphenacodontoidea is a node-based clade that defined to include the most recent common ancestor of the Sphenacodontidae and the Therapsida and their descendants (including mammals). They are defined according to a number of specialised characteristics concerning proportions of the bones of the skull and the teeth.

The Sphenacodontoidea evolved from earlier Sphenacodontia such as Haptodus via a number of transitional stages of small, unspecialised pelycosaurs.

Taxonomy and Phylogeny[edit]

The following taxonomy follows Fröbisch et al. (2011) and Benson (in press) unless otherwise noted.[1][2]

Class Synapsida

References[edit]

  1. ^ Jörg Fröbisch, Rainer R. Schoch, Johannes Müller, Thomas Schindler and Dieter Schweiss (2011). "A new basal sphenacodontid synapsid from the Late Carboniferous of the Saar-Nahe Basin, Germany". Acta Palaeontologica Polonica 56 (1): 113–120. doi:10.4202/app.2010.0039. 
  2. ^ Benson, R.J. (2012). "Interrelationships of basal synapsids: cranial and postcranial morphological partitions suggest different topologies". Journal of Systematic Paleontology. in press. doi:10.1080/14772019.2011.631042. 

See also[edit]