# Petrolacosauridae

> family of tetrapods that developed two holes (temporal fenestra) in each side of their skulls, about 300 million years ago

**Wikidata**: [Q18577568](https://www.wikidata.org/wiki/Q18577568)  
**Source**: https://4ort.xyz/entity/petrolacosauridae


## References

1. Fossilworks
2. Global Biodiversity Information Facility
3. Interim Register of Marine and Nonmarine Genera
4. Open Tree of Life reference taxonomy version 3.6