Late Triassic

Bull Canyon Formation

San Miguel County, New Mexico, USA

Fine 0.6 inch tooth

Reptile, Phytosaur.

Rutiodon is a genus of phytosaur, a group of crocodile-like archosaurs.  It lived in parts of North America during the latter part of the Triassic Period.   Some individuals were larger than any crocodile living today, exceeding 25 feet in length.

Phytosaurs died out during the end-Triassic mass extinction.  The earliest true crocodilians had appeared by that time but they were small, minor elements of the reptile fauna at the time.  For whatever reason they survived the extinction event while many more formidable animals did not.

This is a tooth towards the back of the jaw.