Rastodon

Rastodon Temporal range: Permian
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Order:	Therapsida
Infraorder:	†Dicynodontia
Stem group:	†Bidentalia
Genus:	†Rastodon Boos et al., 2016
Species
R. procurvidens Boos et al., 2016 (type)

Rastodon is an extinct genus of anomodonts. It is the oldest and most basal known genus of bidentalian dicynodonts. Uniquely among dicynodonts, its tusks curve forward.^[1] The type and only species is R. procurvidens.

Etymology

Rastodon is derived from the Rio do Rasto Formation, whence its remains came, and the Greek word for "tooth". The species name, R. procurvidens, means "curved forward tooth" and describes its uniquely shaped teeth.

Provenance

Only a single specimen of Rastodon has been discovered so far. It comes from the Rio do Rasto Formation, of the Guadalupian of Brazil.

Description

Rastodon is a fairly typical dicynodont. It bore a beaked head with a single pair of tusks and a keratin-covered nasal boss. However, it does possess several distinctive traits, of which its anteriorly-curved tusks are the most distinctive. Furthermore, its skull is relatively long and shallow compared to its close relatives. Its tusks contacted the lower jaw during propalinal mastication.

Classification

Rastodon is most parsimoniously placed as the basalmost bidental dicynodont, although it may be slightly more derived within Bidentalia.

See also

• List of synapsids

References