Cricosaurus (Thalattosuchia, Metriorhynchidae) survival across the J/K boundary in the High Andes (Mendoza Province, Argentina)

HERRERA, YANINA; FERNÁNDEZ, MARTA S.; VENNARI, VERÓNICA V.

CRETACEOUS RESEARCH (PRINT)

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Año: 2021 vol. 118

0195-6671

Metriorhynchidae is an extinct group of JurassiceCretaceous crocodylomorphs that developed a fully pelagic lifestyle. Its Jurassic record is outstanding (it includes around 40 nominal species), while the records that can be restricted to the Cretaceous are particularly sparse. Here we describe a partial skull of a new species of Cricosaurus, Cricosaurus puelchorum sp. nov., from the lower Berriasian of the Vaca Muerta Formation (Neuquen Basin, Argentina). The description of the specimen reveals a series of autapomorphies and a unique combination of characters that justify the creation of a new species. Phylogenetic analysis places Cricosaurus puelchorum sp. nov. closer to three upper Kimmeridgiane lower Tithonian species of southern Germany. The new taxon was recovered in connection with an accurate ammonoid-based biostratigraphic control and allows confirming the survival of Cricosaurus across the J/K boundary at the southeastern Pacific.