A new Cenomanian pterosaur tracksite from north-western Patagonia, Argentina

HEREDIA, ARTURO M.; CIAFFI, ALESSIO; BELLARDINI, FLAVIO; GARRIDO, ALBERTO; MANIEL, IGNACIO J. ; BAIANO, MATTIA A.; WINDHOLZ, GUILLERMO J.; GUEVARA, JAVIER E.; MESSINA, MATTIA Y.

Crato

Simposio; 9th International Symposium on Pterosaurs; 2023

Regional University of Cariri

The ichnological pterosaur record is relatively abundant from North America, Europe, and Asia, poorly known from Africa and South America, and completely unknown from Australia and Antarctica. In particular, the pterosaur track record of South America is limited to the Cenomanian Candeleros Formation and the Campanian Anacleto Formation of the Neuquén Basin, Argentina. New pterosaur tracks from the El Sauce locality, Neuquén Province, north-western Patagonia, Argentina, are here reported. They are well-preserved in coarse-grained sandstones from fluvial deposits of the Cenomanian (Upper Cretaceous) Candeleros Formation. Most of the tracks have been found in dislodged blocks but close to the track levels, they are preserved as concave epirelief and a few as a concave hyporelief. Manus tracks are tridactyl, longer than wide (average 10.5 cm long, 5.3 cm wide), and strongly asymmetrical. Pes tracks are longer than wide, and two morphologies can be distinguished, one track is trapezoidal displaying three-digit impressions (12.0 cm long, 4.0 cm wide), whereas the other one is subtriangular showing four-digit impressions (15.5 cm long, 9.0 cm wide). Furthermore, pterosaur tracks associated with small tridactyl dinosaur tracks have been found in at least one block, including a pterosaur manus overprinting a dinosaur track. The morphology of the pterosaur manus tracks is similar to Pteraichnus ichnogenus. Despite both new pes track morphologies seem to be different to any other ichnotaxa, further findings are needed to discern clear diagnostic features and determine whether they belong to a new ichnotaxa. Considering that two such different pes track morphologies have been found, it is likely that they were produced by different groups of pterodactyloid pterosaurs. The new findings from El Sauce improve not only our knowledge on the flying reptile diversification of north-western Patagonia, but also the poorly pterosaur track record of Gondwana.