THE OSTEOLOGY AND PALEOECOLOGY OF THE GIANT OTTER ENHYDRITHERIUM-TERRAENOVAE

The giant otter Enhydritherium terraenovae, a New World taxon thought to be related to both the Old World otter Enhydriodon and the extant s ea otter Enhydra, was originally described on the basis of relatively limited material, mostly dental. However, an incomplete skeleton of E. terraenovae recovered from the early Hemphillian Moss Acres Racetrack site in northern Florida includes a skull, mandible, part of the axia l skeleton, and most of both the fore- and hindlimbs, adding greatly t o knowledge of this animal. On the basis of this new material, the ost eology of this species is described in detail for the first time, with its diagnosis revised accordingly. This new osteological information, along with information about the nature of the Moss Acres Racetrack s ite, allows such paleoecological and functional aspects of E. terraeno vae as habitat preference, mode of swimming, and diet to be inferred o r interpreted in a detail previously impossible. E. terraenovae: 1) wa s a habitat generalist rather than a marine specialist, as previously thought; 2) was reasonably competent for terrestrial locomotion; 3) ex tensively used its forelimbs during swimming like living otariid seals , in contrast to the hindlimb-specialized Enhydra; and 4) had a genera lized diet, potentially including soft items such as fish, as well as hard items, such as thick-shelled molluscs.