Thalassodromeus sebesensis Wasn't a Pterosaur...It was a Turtle

Thalassodromeus sebesensis - a new name for an old turtle. Comment on “Thalassodromeus sebesensis, an out of place and out of time Gondwanan tapejarid pterosaur”, Grellet-Tinner and Codrea

Authors:

Dyke et al

Abstract:

In a recent Gondwana Research article Grellet-Tinner and Codrea (2014) (hereafter “GTC”) describe a single bone (UBB ODA-28, collections of Babeş-Bolyai University, Cluj Napoca, Romania) from the Upper Cretaceous Şard Formation (= middle section of the Sebeş Formation) (Transylvanian Basin, Romania) as a pterosaur premaxillary cranial crest. They assign this fossil to a new species of small pterosaur, Thalassodromeus sebesensis (a name first coined in a conference abstract published in 2013; Grellet-Tinner et al., 2013). GTC build a taxonomic argument on the basis of this single incomplete specimen that posits the presence of a major group of pterosaurs hitherto entirely restricted to the Early Cretaceous of South America - thalassodromines (Kellner and Campos, 2007) or thalassodromids (Witton, 2009) - in the European Late Cretaceous. GTC note that “this important discovery doubles the thalassadromine fossil record and demonstrates a 42 million years temporal displacement between the Romanian species and its older Aptian Gondwanan congener Thalassodromeus sethi”. If GTC are correct, this new fossil represents a remarkably unexpected and potentially very important discovery that could rewrite aspects of pterosaur evolutionary history.

We have assembled a large international team who disagree with the arguments presented by GTC. As we demonstrate, the fossil fragment they describe is misidentified; it is, firstly, not from a pterosaur but is clearly a piece of the shell of the turtle Kallokibotion Nopcsa, 1923 and, secondly, is therefore not the groundbreaking discovery of an ‘anachronistic’ Gondwanan pterosaur in Europe as claimed. Because ODA-28 is not a pterosaur, yet alone a Thalassodromeus, GTC’s conclusions on migration routes and insular dwarfism are also unsupported.

 Original authors stick to their guns, but not nicely.