Abstract

The Long Walk Quarry and Tracksite, both situated in the early Cretaceous Cedar Mountain Formation of the San Rafael Swell region, provide important new data on the composition and structure of dinosaur communities during the interval separating well-documented dinosaur faunas of late Jurassic and late Cretaceous age in the Colorado Plateau. At least three different dinosaurs are represented by the remains recovered thus far from the quarry: a juvenile individual referred to the sauropod genus Pleurocoelus, an adult sauropod probably also representing Pleurocoelus, and a large theropod, probably similar to Acrocanthosaurus. The Long Walk Tracksite yields an ichnofauna dominated by medium to large tridactyl impressions. The Long Walk Quarry and Tracksite are born still in the early stages of investigation and will likely produce much more information on the poorly-understood early Cretaceous terrestrial vertebrate fauna of the east-central Utah region.