PRELIMINARY REPORT OF TRACK MORPHOLOGIES IN THE AREA OF MARY ANN’S TRACKSITE, FERRON SANDSTONE, CENTRAL UTAH

Tracks from the Turonian portion of the upper Ferron Sandstone in central Utah have been rarely reported. This study reports measurements of 102 tracks from the area of Mary Ann’s Tracksite. The tracks are all tridactyl, preserved largely as molds on Mary Ann’s tracksite and as eroded natural sandstone casts from the three-meter interval immediately above this surface. Tracks range from lengths of 12 – 47 cm (26.7 cm average) and widths of 9.5 – 60 cm (26.1 cm average). Three morphologies are preliminarily distinguished in this area based on tracks displaying well-defined margins. Morphology 1 is comparable to Iguanodontipus with three well-defined digits, wider than long overall morphology, a symmetrical appearance, and blunt terminations. Morphotype 2 is similar in appearance except the interdigital areas are connected, potentially suggesting webbing between toes. This second morphotype is comparable to Amblydactylus. Morphotype 3 is also tridactyl, but has a width decrease, a slightly longer digit III, and sharp digit terminations that are similar to Therangospodus. Initial investigation of this interval indicates that ornithopod tracks (Iguanodontipus and Amblydactylus) are more prevalent, with theropod tracks (potential Therangospodus) being rare. These tracks provide more information on an interval that has been rarely report from and the overwhelming number of ornithopod tracks may eventually provide information on population dynamics or depositional environmental preferences at this site.