Hadrianus is an extinct genus of tortoise belonging to the Testudinidae[1] found in the United States, the Yolomécatl Formation of Mexico, the Alai Beds of Kyrgyzstan and Spain[citation needed] and believed to be the oldest true tortoise known.

[3] The genus may have evolved in the subtropics of Asia and subsequently migrated to North America and Europe.

[3] Evangelos Vlachos (2018) reassessed the North American species attributed to the genus, and determined only two as accepted namely H. corsoni & H. majusculus.

The remaining species were identified as either junior synonyms, moved to other genera or considered nomen dubium do to incomplete fossils.

This article about a prehistoric turtle is a stub.