Petrustitan

Petrustitan was a dwarf titanosaurian sauropod that inhabited the ancient Hateg Island of modern Romania during the Late Cretaceous epoch, around 70 million years ago. For almost a century its fossils were classified under the name Magyarosaurus hungaricus until detailed anatomical reappraisals revealed it represented a distinct genus. Measuring roughly six metres in length and weighing over a tonne, it was remarkably small for a sauropod, having evolved diminished body proportions through insular dwarfism in response to the limited resources of its island home. Like its close relatives, Petrustitan walked on all fours and browsed low to medium vegetation using peg-like teeth. The discovery and eventual separation of Petrustitan highlight the surprising diversity of small sauropods that flourished in the prehistoric archipelagos of Late Cretaceous Europe.

Named in 2025 for Transylvanian fossils previously lumped into Magyarosaurus hungaricus.

Where and when

Petrustitan lived in the Late Cretaceous, from 72.1 to 66 million years ago (Maastrichtian age). Its remains come from Romania, in the Sânpetru Formation.

The numbers

Length 6 m (estimates run from 5 to 7 m). Mass about 1.3 t. Hip height about 1.5 m. That is 3.5 human-lengths, or 0.54 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, hip height.

Compare Petrustitan with a bus Place on the timeline