First Record of Theropod and Ornithopod Tracks and Detailed Description of Sauropod Trackways from the Tacuarembó Formation (Late Jurassic-?Early Cretaceous) of Uruguay

Abstract

The record of dinosaur tracks and trackways from the Tacuarembó Formation (Late Jurassic-?Early Cretaceous) is described in detail: two trackways and four isolated tracks. Ichnites are preserved in sandstones of interdune facies of the Batoví (lower) Member. The interpretation herein presented indicates a sauropod affinity of the trackways, while the isolated prints are considered to have been made by an ornithopod and small theropods. The fossil record for this formation was primarily integrated by fresh-water organisms. The presence of new groups (sauropods and ornithopods) has specially contributed to the reconstruction of the terrestrial fauna, represented up until this time only by theropods.

Keywords:

• Late Jurassic-?Early Cretaceous
• Tacuarembó Formation
• dinosaur tracks
• Sauropods
• Theropods
• Ornithopods

ACKNOWLEDGMENTS

The authors wish to thank the following colleagues for fieldwork support: Pablo Toriño, Gustavo Lecuona, Matías Soto, Andrea Corona, Guillermo Roland, Fernanda Cabrera, Andrés Batista, Lucía Samaniego and Martín Ubilla. The extremely helpful reviews by Hendrik Klein and Matteo Belvedere greatly improved the quality of this manuscript.

Funding

This work is a contribution to Projects FCE 2009 2843 and CSIC C028-348, financed by the ANII (Agencia Nacional de Investigación e Innovación) and the CSIC (Comisión Sectorial de Investigación Científica), respectively.