Skeletal remains of the extinct mountain goat Oreamnos harringtoni and Marmota (marmot), an extralimital species, were recovered from Marmot End Alcove along with remains of montane plants that included Pseudotsuga menziesii (Douglas-fir), Picea (spruce), Pinus flexilis (limber pine), and Juniperus communis (common juniper). The alcove is located in Harris Wash, a semiarid tributary in an unstudied portion of the Escalante River Basin on the Colorado Plateau in southern Utah. A Marmota incisor tooth and montane plant needles returned late Pleistocene AMS dates ranging from 12,300 yr BP to 15,600 yr BP.