NEWLY ACQUIRED MIOCENE VERTEBRATES FROM WEBSTER COUNTY, SOUTH-CENTRAL NEBRASKA, USA

In June, 2011, the University of Nebraska State Museum (UNSM) was gifted a large number of Miocene vertebrate fossils known as the Fitzgibbon Collection from the Webster County Museum in Red Cloud, Nebraska. Since 1983, Jim Fitzgibbon, a local high school teacher, has monitored known UNSM vertebrate sites, where he salvaged newly exposed materials and actively quarried some sites with student help from throughout the local communities. Through the years over twenty new localities were discovered and several were developed to the point where an astounding array of fossils was collected. There are nearly 6,800 expertly cataloged entries in this collection with the total number probably exceeding 30,000 individual specimens! The collection includes micro- and macrofossils of fish, amphibians, reptiles, birds, and mammals. This new material enhances our knowledge of the Penny Creek local fauna (Ash Hollow Formation, early Clarendonian North American Land Mammal Age) and the Myers Farm local fauna (Valentine Formation, late Barstovian).

Initial studies of the new material verify earlier conclusions that the two local faunae are more closely allied to Gulf Coast sites than they are to age-equivalent northern Nebraska localities with the climate being somewhat warmer in southern Nebraska, perhaps even sub-tropical. In Webster County small, low-crowned artiodactyls are in abundance as are anchitheriine browsing horses, primitive camels with unfused metapodials, and the unusual nasal-horned protoceratids. In addition Alligator is a common constituent of the Myers Farm Local Fauna and only rarely encountered in northern Nebraska. A large and more varied testudine collection is present, with several species of chelydrids and perhaps including a new tortoise and a new giant soft-shelled turtle. Preliminary work indicates the presence of the bizarre long-nosed camelid, Floridatragulus, and a new very large late Barstovian antilocaprid, intermediate in size between Proantilocapra and the extant Antilocapra.