An Updated Review of the Avian Footprint Record from the Yacoraite Formation (Maastrichtian-Danian), Northwestern Argentina

Abstract

The Yacoraite Formation (Maastrichtian–Danian; Balbuena Subgroup; Salta Group), from Northwestern Argentina, represents a shallow epeiric unit which is the result of transgressions in the Andean basin of South America. Herein, we study the avian footprints from the Maimará locality, Jujuy province, and Quebrada del Tapón ichnosite, Salta province. The avian footprints from the Maimará locality is less diverse, made up: cf. Alaripeda isp., Avipeda isp., cf. Gruipeda filiportatis, and cf. Gruipeda isp. The avian track record from the Quebrada del Tapón ichnosite is composed of: cf. Alaripeda isp., Ardeipeda cf. egretta., Gruipeda filiportatis (=Yacoraitichnus avis) and others Gruipeda or compared to this ichnogenus, cf. Uhangrichnus isp., and several indetermined avian footprints. Both ichnological assemblages have tracks assigned to shorebirds or Charadriiformes. The facies distribution of trace fossils reinforces the overall model of a shorebird tracks dominance in moderate to low energy settings. This distribution can be divided into three sub-environments: (1) a moderate to high energy shoreline under wave action, (2) a supratidal body of ephemeral ponds, far away from direct wave influence and (3) a landward position, beyond the ephemeral ponds system. We have included all the ichnoassemblages within the shorebird ichnosubfacies as a subset of the Scoyenia Ichnofacies.

Keywords:

• Avian footprints
• Yacoraite Formation
• Cretaceous
• Gondwana

Acknowledgements

We are grateful to colleagues P. Herrera, P. Machuca, D. Lizarraga and M. Griffin for their help in different stages of the fieldwork. We are also very grateful to the CNEA and the people working on Mina Don Otto for their invaluable help in the fieldwork, especially to S. Gorustovich and A. Zelaya, who have invited us to study the Valle del Tonco locality and provided valuable geological information and support. We wish to thank the editors M. Gingras and H. Klein for the accompaniment in the editorial paths of the journal, and the reviewers I. Díaz-Martínez and L. G. Buckley for their great job, which finally managed to improve our manuscript.

Additional information

Funding

This research was supported by grants PICT 1665 (C. Cónsole-Gonella) and PICT 2057 (C. Cónsole-Gonella and S. de Valais) from the Agencia Nacional de Promoción Científica y Técnica, and PIUNRN 40-A-402 (S. de Valais) from Universidad Nacional de Río Negro.