The giant tapir, Tapirus haysii, from Leisy Shell Pit 1A and other Florida Irvingtonian localities

Abstract

Twelve new records of the giant North American tapir Tapirus haysi, are reported from Alachua, Levy, Citrus, Polk, and Hillsborough counties, Florida. Biochronologic analysis of associated vertebrates indicates T. haysii was limited to the late early-middle Irvingtonian (ca. 1.5-0.6 Ma) in Florida. The sample of T. haysii from the Leisey Shell Pit 1 A site is the most complete yet recovered, and second only to the Port Kennedy Cave population in numbers of measurable teeth. All known cranial features of T. haysii resemble those of T. veroensis, including a low, double-ridged sagittal crest, ontogenetically delayed fusion of the interparietal with adjacent cranial elements, massive mandibular ramus, and relatively short diastema. Phylogenetic analysis of New World Tapirus produces two equally parsimonious cladograms. In both, T. haysii and T. veroensis form one monophyletic clade, and the extant Neotropical species T. pinchaque, T. terrestris, and T. bairdii another. They differ with respect to the position of T. simpsoni, a late Miocene North American species.