Thalassodromeus sebesensis: A Chronologically & Geographically Unexpected Maastrichtian Cretaceous Tapejarid Pterosaur

Thalassodromeus sebesensis, an out of place and out of time Gondwanan tapejarid pterosaur

Authors:

Grellet-Tinner et al

Abstract:

We report here the first occurrence of a small pterosaur, Thalassodromeus sebesensis from the Maastrichtian Hateg Island. This new species with its significantly expanded premaxillary crest extends the known distribution of this genus from South America to Europe. Furthermore, this important discovery doubles the thalassadromine fossil record and demonstrates a 42 million years temporal displacement from its older Aptian Gondwanan congener Thalassodromeus sethi. Thalassodromeus sebesensis sp. nov. is diagnosed by an unusual expanded premaxillary crest and synapomorphies shared only with its Brazilian congener, T. sethi. Yet, the new specimen displays enough autapomorphic characters to erect a new thalassodromine species. The discovery of Thalassodromeus sebesensis in an exposure known for its diverse angiosperm assemblage lends more support to the tapejarid and flowering plants co-evolution. It also suggests this new small thalassadromine was a forest dweller, as such possibly not competing with the known giant azhdarchid pterosaurs on this island. Moreover, its presence in this insular ecosystem confirms once more the aberrant nature of the Late Cretaceous Hateg island-dwelling endemic fauna.