The first Late Cretaceous dinosaur tracksite recorded from Arizona, preserving over 100 footprints, also preserves sinuous grooves here interpreted to be impressions left by the tail of a large vertebrate as it dragged through sediment now assigned to the Toreva Formation. Although no footprints are preserved that can be referred unambiguously to the individual or individuals that produced the tail-drag marks, the dynamic nature of the surface upon which the tracks were made, likely a river or stream shoreline, could have easily resulted in their disturbance or obliteration. As best as can be determined on the basis of a depauperate marine fauna from the lower part of the unit, and on the basis of a substantial hiatus that separates the lower and upper parts, the site is probably middle Coniacian in age. These tracks and drag marks add significantly to the exceptionally rare record of terrestrial vertebrates known from the Toreva Formation.

You do not currently have access to this article.