Story perspectives

Ancient Fossil Challenges Lizard Evolution Theories

9/14/2025

40 3

Summary

Story summary

The 242-million-year-old fossil Agriodontosaurus helsbypetrae from Devon challenges current lizard evolution theories.
This 10-centimeter predator lacks features like hinged skulls and palate teeth.
Its large triangular teeth suggest a unique feeding strategy for piercing insect exoskeletons.
The discovery extends the timeline of lepidosaur evolution by up to 7 million years.
Agriodontosaurus is the most complete Triassic lepidosaur found in Britain, predating dinosaurs.

1 of 1

Story summary

The 242-million-year-old fossil Agriodontosaurus helsbypetrae from Devon challenges current lizard evolution theories.
This 10-centimeter predator lacks features like hinged skulls and palate teeth.
Its large triangular teeth suggest a unique feeding strategy for piercing insect exoskeletons.
The discovery extends the timeline of lepidosaur evolution by up to 7 million years.
Agriodontosaurus is the most complete Triassic lepidosaur found in Britain, predating dinosaurs.