Sphenosuchus is an extinct genus of crocodylomorph from the Early Jurassic Elliot Formation of South Africa, discovered and described early in the 20th century. The skull is preserved very well but other than elements of the forelimb and isolated parts of the hind limb, the Sphenosuchus material is incomplete. It was probably quadrupedal, but may have been a facultative biped.
Sphenosuchus
Sideview of Sphenosuchus acutes skull as portrayed by the South African Museum
Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. Extinct crocodylomorphs were considerably more ecologically diverse than modern crocodillians. The earliest and most primitive crocodylomorphs are represented by "sphenosuchians", a paraphyletic assemblage containing small-bodied, slender forms with elongated limbs that walked upright, which represents the ancestral morphology of Crocodylomorpha. These forms persisted until the end of the Jurassic. During the Jurassic, crocodylomorphs morphologically diversified into numerous niches, with the subgroups Neosuchia and the extinct Thalattosuchia adapting to aquatic life, while some terrestrial groups adopted herbivorous and omnivorous lifestyles. Terrestrial crocodylomorphs would continue to co-exist alongside aquatic forms until becoming extinct during the Miocene.
Crocodylomorpha
Life restoration of Hesperosuchus