Lower Cretaceous Dinosaur Tracks from Puebla, Mexico

Rubén A Rodríguez-De La Rosa,Arturo Ortiz-Ubilla,Enrique Carrillo-Montiel,Víctor M Bravo-Cuevas

doi:10.1155/2012/808729

Abstract

Dinosaur tracks have been identified near San Martín Atexcal, southern Puebla, Mexico, within the sedimentary sequence of the San Juan Raya Formation of Lower Cretaceous (Albian) age. The tracksite, located in the bed of the Magdalena River, reveals six different ichnofossiliferous levels identified within a 9 m thick sedimentary sequence. The inferred environment is that of a tidal (marginal marine) mudflat (Level I). Level I preserves three theropods trackways (?Allosauroidea), additionally, isolated tracks belonging to iguanodontids (Ornithopoda). Level II preserves faint iguanodontid tracks. Levels III to V preserve sauropod tracks. Younger level VI preserves, although morphologically different, a track belonging to Ornithopoda. The dinosaur tracks from San Martín Atexcal support the existence of continental facies within the San Juan Raya Formation; they represent the second record of dinosaur tracks from the Lower Cretaceous of Mexico and are part of an important but little documented record of Lower Cretaceous dinosaurs in Mexico.

Highlights

Since the first report on dinosaur tracks from Mexico, the number of reported localities has increased considerably [1,2,3]
Dinosaur tracks have been identified near San Martın Atexcal, southern Puebla, Mexico, within the sedimentary sequence of the San Juan Raya Formation of Lower Cretaceous (Albian) age
The dinosaur tracks from San Martın Atexcal support the existence of continental facies within the San Juan Raya Formation; they represent the second record of dinosaur tracks from the Lower Cretaceous of Mexico and are part of an important but little documented record of Lower Cretaceous dinosaurs in Mexico

Summary

Introduction

Since the first report on dinosaur tracks from Mexico, the number of reported localities has increased considerably [1,2,3]. The evidence of Mexican dinosaurs of Lower Cretaceous age is restricted to the site reported here (see [3, 4]). This track site is located near the small town of San Martin Atexcal in southern Puebla, central Mexico (Figure 1), and it represents the first known dinosaur track site of this age from Mexico. Recently discovered, reveal more dinosaur tracks within the San Juan Raya Formation; these remain unstudied. The site reported reveals dinosaur tracks in at least six different stratigraphic levels in the upper part of the San Juan Raya Formation. The objective of this paper is to document this dinosaur track site, to comment on the observed ichnofaunal succession, and place the information regarding the tracks in the broader context of the Lower Cretaceous dinosaur paleoichnology

Objectives

Methods

Conclusion