FOSSIL BATS OF THE AMERICAS
The Seaboard LF was collected from the lower Torreya Formation in Tallahassee, Leon County, Florida panhandle. The Seaboard LF is predominantly composed of large mammals, most of which are shared with the early Hemingfordian Thomas Farm LF, including (from Olsen 1964): the horses Parahippus leonensis, Archaeohippus blackbergi, and Anchitherium clarencei, the rhinocerotid Menoceras, and the protoceratid Prosynthetoceras texanus. Although sediments from the Seaboard site were not extensively screenwashed at the time the site was discovered in the early 1960s, two small mammals are known from the site, including an upper molar of a vespertilionid bat and the small heteromyid rodent Proheteromys floridanus. The Seaboard LF also has a significant sample of marine vertebrates, including sharks, rays, and bony fish.
The Seaboard LF and Thomas Farm are very similar in age (early Hemingfordian, 18-19 Ma) based on the joint occurrence of the horses Parahippus leonensis, Archaeohippus blackbergi, and Anchitherium clarencei, the protoceratid Prosynthetoceras texanus, and the rodent Proheteromys floridanus. Strontium isotope geochronology of the oyster Ostrea from the Seaboard LF yielded an age estimate of 18.4 Ma (Bryant et al. 1992), which agrees very closely with the early Hemingfordian age indicated by the mammalian biochronology.