Discriminating between medium-sized Tridactyl Trackmakers: tracking Ornithopod tracks in the base of the Cretaceous (Berriasian, Spain)

PLoS One. 2013 Nov 26;8(11):e81830. doi: 10.1371/journal.pone.0081830. eCollection 2013.

Abstract

Background: Recent work on the Jurassic-Cretaceous transition of the Iberian Range (Spain) has opened a new window onto the interpretation of the trackmakers of some medium-sized tridactyl tracks. The ichnotaxon Therangospodus oncalensis has been described in the Huérteles Formation (Berriasian) and is one of the classical tracks from the area assigned to medium-sized theropods.

Methodology/principal findings: A review of the type locality of Therangospodus oncalensis (Fuentesalvo tracksite) and other tracksites from the Huérteles Formation (Berriasian) has yielded new information on the morphology, gait and trackmaker identity of the aforementioned ichnospecies. The new data suggest that the trackmaker is an ornithopod rather than a theropod on the basis of the length/width ratio, the anterior triangle length-width ratio, the short steps, the round to quadrangular heel pad impression and the probable manus impressions.

Conclusions/significance: T. oncalensis shows similarities with various tracks from the Berriasian of Europe assigned to Iguanodontipus. The ichnotaxonomical status of this ichnospecies is here considered as Iguanodontipus? oncalensis due to the current state of knowledge of the ichnotaxonomy of medium-sized ornithopod tracks. This reassessment of I? oncalensis also has two significant implications for the palaeoecology of the faunas during the deposition of the Huérteles Formation: 1- the high number and percentage of theropod tracks would be lower than previous papers have suggested. 2- the gregarious behaviour described in the type locality (Fuentesalvo) would be among ornithopods instead of theropods.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dinosaurs*
  • Paleontology*
  • Spain

Grants and funding

This paper is a contribution to the projects CGL2011-30069-C02-01 and CGL2010-16447, subsidized by the Ministerio de Ciencia e Innovación of Spain, the European Regional Development Fund, the Government of Aragón (“Grupos Consolidados”). DC is the beneficiary of a grant from the Ministry of Education (AP2008-01340). BV acknowledges support from the Ministry of Science and Innovation (Subprograma Juan de la Cierva (MICINN-JDC) 2011). NLR is the beneficiary of a grant from the project CGL2011-30069-C02-01. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.