New rebbachisaurid remains from the Huincul Formation (Middle Cenomanian–Early Turonian) of the Central Neuquén Basin, Patagonia, Argentina.

BELLARDINI, FLAVIO; FILIPPI, LEONARDO SEBASTIÁN; GARRIDO ALBERTO CARLOS; CARBALLIDO JOSÉ LUIS; BAIANO, MATTIA A

Revista Electrónica de la Asociación Paleontológica Argentina

Asociación Paleontológica Argentina

Lugar: Buenos Aires; Año: 2022 vol. 22 p. 1 - 24

2469-0228

In the central Neuquén Basin, the Huincul Formation comprises thick successions of Upper Cretaceous fluvial deposits widelyexposed at the south and north-west of Huincul High. The vertebrate fossil record from the Huincul Formation is very abundant, especiallyconsidering the saurischian dinosaurs, including several theropod (Mapusaurus, Taurovenator, Aoniraptor, Skorpiovenator, Ilokelesia, Gualicho,Overoraptor, Tralkasaurus, and Huinculsaurus) and sauropod specimens (Choconsaurus, Argentinosaurus, Cathartesaura, Limaysaurus, and theindeterminate rebbachisaurid MMCH-Pv-49). In this contribution, we describe new rebbachisaurid sauropod findings from the El Orejano locality(Neuquén Province, Argentina), where coarse sandstones outcrop referred to the lower section of the Huincul Formation. The new materialincludes three axial elements that we refer to Rebbachisauridae: a partial dorsal neural arch (MAU-Pv-EO-633), an incomplete dorsal vertebra(MAU-Pv-EO-634), and an almost complete caudal vertebra (MAU-Pv-EO-666). These new findings share different features with othermembers of that family, although show some morphological differences with other rebbachisaurid taxa, which suggest a more diversifiedfauna in the central Neuquén Basin than previously known, at least during the Cenomanian/Turonian interval. This record from the newfossiliferous locality of El Orejano allows us to improve our knowledge about the morphological diversity of the Rebbachisauridae during theearly Late Cretaceous. Furthermore, it represents one of the most modern records of the family, adding new information on the last stages ofthe evolutionary history of rebbachisaurids.