THE PLEISTOCENE MAMMALS OF COSTA-RICA

Fossil mammals are known from 41 localities of Pleistocene age in Cost a Rica. Most of these mammals are proboscideans referable to the gomph othere Cuvieronius hyodon. One occurrence of Haplomastodon waringi is known, and Mammuthus columbi from Costa Rica is the southernmost recor d of Mammuthus in Central America. Less well documented are occurrence s of megatheriid and mylodontid ground sloths and glyptodonts. Equus i s poorly known from several localities, and the toxodont Mixotoxodon l arensis is well known from a single locality. Canis latrans and Tapiru s sp., cf. T. terrestris are new records for the Pleistocene of Costa Rica. None of the Costa Rican Pleistocene mammals is directly associat ed with human artifacts or remains. No endemic taxa of mammals are kno wn from Costa. Rica; most are of North American origin. The Costa Rica n Pleistocene record is from numerous localities, but consists of one or a few taxa of large mammals and no small mammals at each site, indi cating a probable bias towards preservation in high energy fluvial dep osits, alluvia, ignimbrites, and lahars, and a collecting and/or prese rvational bias toward fossils of large size.