Additional arvicolines and cricetids from the Fiene local fauna (Irvingtonian) of north-central Kansas

摘要

Two cricetids and three arvicolines are added to the Fiene local fauna (Irvingtonian) of north-central Kansas. Cricetids include the harvest mouse, Reithrodontomys moorei and grasshopper mouse, Onychomys sp. Arvicolines include the muskrat, Ondatra annectens, red-backed vole, Myodes gapperi, and bog lemming, Mictomys kansasensis. The latter two; taxa are extralimital and indicate cooler and wetter summers than at present in the area. Likewise, the record of Myodes represents the earliest occurrence of the taxon on the central Plains. The rarity of Onychomys relative to the previously reported abundant microtids in the Fiene local fauna indicates that the transition from a granivorous diet in the Blancan to a primarily insectivorous diet it has today was completed during Irvingtonian II.