Agriodontosaurus (meaning fierce-toothed lizard) is an extinct genus of early rhynchocephalian reptile that lived in Middle Triassic of England. The type species is Agriodontosaurus helsbypetrae.
Discovery and Naming[]
The holotype (BRSUG 29950-14) was discovered by Robert A. Coram in 2015 in a sandstone bed in Helsby Sandstone Formation. In 2025, it was described by a group of scientists. The generic name combines Agrionius, Donto, and Sauros, while the specific name is named after the formation where it was discovered, combined with Greek word Petra.
Description[]
It is one of the smallest rhynchocephalians, with a body around 10 centmeters (3.9 in) long. The specimen is fragmented, but well-preserved. the specimen comprises much of the skull, mandible, eight neck vertebrae, and few back vertebrae. It has robust teeth at the front of the upper and lower jaws, which become more triangular towards the further back. It lacks a complete temporal bar connecting the jugal bone with the quadrate bone. The preparation revealed much of the anatomy, as some of them were clearly visible when it was excavated. It is probably an insectivore.
Classification[]
It is classified as a member of Acrosphenodontia inside the clade Rhynchocephalia.
Gallery[]
