Late Kansan Faunas from Central Kansas

Abstract

Fossil molluscs and mammals were studied from four late Kansan faunas (Cedar Bluff Canal, Holzinger, Tobin, Wilson Valley) recovered from alluvial fill deposits along the Saline and Smoky Hill river valleys in central Kansas, for which, primarily, only faunal lists had been published more than 25 years ago. A review of the original collections, plus subsequently collected materials, allows us to add 35 taxa to the faunas (9 to Cedar Bluff Canal, 11 to Holzinger, 6 to Tobin, 9 to Wilson Valley). Paleoclimatic inferences drawn from analysis of the faunas suggests that Kansas enjoyed its coolest climate during the time these faunas lived. In addition the central part of the state enjoyed more effective precipitation than at present. Data from the Trego County faunas, which are superposed, suggests a slight warming trend as Gastrocopta cristata and G. procera are present in the younger fauna (Holzinger), whereas Vertigo modesta is present in the older fauna (Cedar Bluff Canal). This relationship plus the presence of G. procera in the Wilson Valley local faunas and the unsubstantiated report of V. modesta in the Tobin local faunas suggests that although the faunas fall within the late Kansan stage they may differ in absolute age among themselves and from the Cudahy local faunas. In an attempt to extend the faunal sequence established by the late Claude W. Hibbard for southwestern Kansas, individuals and field parties from Fort Hays State University have been exploring the late Cenozoic deposits in central Kansas along and between the Smoky Hill and Saline river valleys. Fossils from this area had been collected by parties from the Kansas Geological Survey in the 1930's, but had been subjected to little detailed study. In the course of this work, additional vertebrate material has been obtained