Bastetodon


Bastetodon is an extinct genus of carnivorous hyaenodont mammal from the Early Oligocene Jebel Qatrani Formation of Egypt. The genus contains single species, B. syrtos, which was originally assigned to the genus Pterodon. It was a medium-sized hyaenodont, with an estimated body mass ranging around.

Discovery and naming

In 1999, paleontologist Patricia A. Holroyd described a partial right maxilla from 'Quarry M' of the Jebel Qatrani Formation near the Faiyum Oasis of Egypt as belonging to a new species of Pterodon, P. syrtos. The specific name, syrtos, is a Greek word meaning "carried along by a stream", referencing the preservation of the holotype in a point bar depositional environment.
In 2025, Al-Ashqar and colleagues revised the record of African species assigned to Pterodon, a historic wastebasket taxon. As in previous analyses, they observed that the species referred to this genus form a polyphyletic assemblage. Based on a more recently-collected complete skull from 'Quarry I', they established a new genus, Bastetodon, for "P." syrtos. The generic name combines a reference to Bastet—a cat-headed goddess from Ancient Egyptian mythology associated with protection, pleasure, and good health—with the Greek suffix "-odon", meaning "tooth". The authors' intended translation is "teeth like the cat-headed goddess".

Classification

Using an expanded matrix from previous phylogenetic analyses, Al-Ashqar et al. recovered "P." syrtos as the sister taxon to the smaller and roughly coeval Falcatodon within the hyaenodontan subfamily Hyainailourinae. Their results are displayed in the cladogram below:

Description

Size

The body mass of hyaenodonts is problematic as the sister-taxon of the order remains unresolved. The body mass of Bastetodon was based on Van Valkenburgh regression of total skull length and the distance from the orbital condyles to the anterior orbit. Based on the regressions, Bastetodon could’ve weighed, based on OOL and SKL respectively, with a mean body mass of.

Skull

The skull of Bastetodon was not only the most complete of any hyaenodont from the Jebel Qatrani Formation, but also the most best preserved of any Paleogene Afro-Arabian hypercarnivore.

Paleobiology and paleoecology

Predatory behavior

The long, shearing metastyles and the reduced and mesially shifted protocones suggests Bastetodon had a hypercarnivorous diet. The loss of P1 and M3 suggests Bastetodon also had a powerful bite force.

Paleoecology

Bastetodon was found within the Jebel Qatrani Formation of Egypt of the Early Oligocene. It was thought to have been a subtropical to tropical swamp being comparable to that of freshwater habitats in Central Africa. Based on sediments, there was likely a river system of channels that emptied west towards the Tethys. The climate was likely seasonal, and potentially monsoonal.