Tapinocaninus

Tapinocaninus (Greek for "humble"- tapino, and "canine"- caninus) is an extinct genus of therapsids in the family Tapinocephalidae, of which it is the most basal member.

Air scribe machinery was used to prepare the specimens, along with manual tools such as a hammer and chisel in areas where matrix was more abundant.

When comparing features of Tapinocaninus to those discussed of Tapinoceohalinae through a cladistic analysis, Rubidge et al. (1991) found that a synapomorphy of the two were the expanded heels on the incisor teeth.

[2] With classic regression formulas using the circumference of the humerus and femur bones, researchers approximated that they averaged a body mass of 892.63Kg for the taxon (nearly 2,000lbs).

[5] The skull roof and postorbital bar of Tapinocaninus shows pachyostotic thickening, which is consistent with other tapinocephaline dinocephalians.

The maxilla forms a majority of the lateral area of the face, and it is swollen to allow room for the root of the canine tooth.

[6] The temporal openings are relatively large, and subsequently, Tapinocaninus has a narrow intertemporal region, which is considered a primitive feature of Tapinocephalinae.

[7] Additionally, these taxon have a thin snout, sloping occipital, relatively small quadratojugal, prominent stapedial foramen, and relatively anterior position of the quadrate.

Over half the length of the palate is the pterygoid, and it has lateral flanges that extend ventrally and transversally.

This feature is primitive for therapsids, another ancestral trait for this clade also includes the presence of intercentra in between the cervical vertebrae.

[2] Their vertebral structure suggests that tapinocaninus had very short tails similar to anomodonts, but in contrast to anteosaurids.

[2] The pelvic girdle of the holotype NMQR 2987 is partially preserved, and the other specimens are also lacking of a complete structure.

Their intermediate posture is can be explained by their long bones, in addition to the shape and positioning of the humerus and medially inflected femur.

[2] Additionally, the presence of intercentra only in the anterior dorsal vertebrae and medial directed zygapophyses in Tapinocaninus suggests that they had less undulatory locomotion in when compared to sphenacodonts.

[14] The zone is identified by the existence of Eodicynodon oosthuizeni, a dicynodont, along with Tapinocaninus pamelae and Australosyodon nyaphulii, two types of dinocephalians.

Fossils of tetrapods are rare in this area, however, there are copious impressions of equisetalian and Glossopteris stems and leaves on the mudrock surfaces.