Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

Journal of Paleontology

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by HOPKINS, S. S. B. Search for Related Content GeoRef GeoRef Citation

PHYLOGENY AND BIOGEOGRAPHY OF THE GENUS ANSOMYS QIU, 1987 (MAMMALIA: RODENTIA: APLODONTIDAE) AND DESCRIPTION OF A NEW SPECIES FROM THE BARSTOVIAN (MID-MIOCENE) OF MONTANA

¹ Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley 94720, <shopkins{at}socrates.berkeley.edu>

New aplodontid material recovered from Hepburn's Mesa, Montana, stimulated reexamination of Ansomys, a genus of aplodontid previously known only from Asia. A cladistic analysis of the known species of Ansomys, as well as new material from Hepburn's Mesa and a few other morphologically similar species, prompted reconstruction of the biogeographic history of the genus. One new species, A. hepburnensis, from the Barstovian of Montana, is described, and two other species, A. nexodens and A. descendens, are placed in Ansomys rather than in Pseudallomys and Plesispermophilus, respectively. Addition of these three species to Ansomys extends its distribution throughout the Holarctic in the mid-Miocene. Stratigraphic ranges combined with phylogenetic relationships between species suggest this wide distribution as early as the late Oligocene, which is unique among aplodontid genera. The distribution, the rarity, the unusually small size, and the complex cusp morphology of Ansomys suggest a very specialized ecology for members of this clade.