Pauromys and other small Sciuravidae (Mammalia: Rodentia) from the middle Eocene of Texas

ABSTRACT The southernmost Uintan (middle to late middle Eocene) vertebrate faunas in North America occur in Trans-Pecos Texas and in the Texas Gulf Coast province at Laredo. Small rodents, mainly represented by isolated teeth, are among the most abundant faunal elements. These rodent faunas show high endemism and a Uintan refugium in Texas for some forms which fail to persist in the better-known coeval faunas of the Northern Interior. Two new species of Pauromys (P. texensis, sp. nov. and P. simplex, sp. nov.) are described, as well as other small Sciuravidae, extending the known range of Pauromys southward to the Gulf Coast and late into the Uintan. Pauromys was the ecological equivalent of modern Peromyscus or Mus in being small, abundant, and with several syntopic species.

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