We report the youngest radiocarbon determination so far for an identified species of Antillean sloth, 4190 ± 40 yr BP, based on a molariform of Megalocnus rodens from the locality of Solapa de Silex, Lomas de Cacahual, prov. La Habana, Cuba. Together with other recently reported age estimates, the evidence is now secure that at least some Antillean sloth species survived until ca. 4200 yr BP, or approximately 1000 yr later than the first plausible evidence for the presence of humans in the Greater Antilles. The survival of relatively large terrestrial mammals for such a lengthy period after the arrival of Homo sapiens indicates that insular extinctions in the Late Quaternary did not always occur in a “blitzkrieg” manner.