Insectivores, rodents, and carnivores of the Toledo Bend Local Fauna: an Arikareean (earliest Miocene) assemblage from the Texas Coastal Plain

Abstract

ABSTRACT Material representing at least six different species of rodents, one insectivore, and two carnivores was recovered from a submerged paleochannel deposit in the lower part of the Fleming Formation, near the Toledo Bend Dam in easternmost Texas. A “middle” Arikareean Land Mammal Age for this Gulf Coastal Plain fauna is implied by its similarity with other faunas of comparable age in Florida and the northern Great Plains, such as the Buda Local Fauna and the Monroe Creek Fauna, respectively. The rodents from the Toledo Bend Local Fauna include the squirrel Protospermophilus, the castorid “Monosaulax” hesperus, and a possible new genus and species of eomyid or cricetid remarkably similar to the European middle Oligocene cricetid Pseudocricetodon montalbanensis. Two new species of heteromyid, Proheteromys sabinensis and P. toledoensis, are described, and a temporal and spatial range extension is noted for the rare geomyoid Texomys. A tiny “mustelid” tentatively referred to Palaeogale is recorded, as is the first occurrence outside of Florida of the amphicyonid Daphoenodon notionastes.