THE FOSSIL RECORD OF CALLITRICHINE PRIMATES

Six out of the 16 recognized species of fossil New World monkeys have been discussed as possible relatives of the modern callitrichines. The dental evidence for these views is examined, with emphasis on the homologies and polarities of the relevant characteristics. We conclude that there is no support for the idea that eitherXenothrix or"Saimiri" bernensis are related to callitrichines, thus leaving unconfirmed the interpretation that some subfossil postcrania from the Caribbean pertain to the group. The middle Miocene La Venta formsMicodon andMohanamico (shown not to be synonymous withAotus dindensis) appear to be callitrichines; the first, largely on account of its very small size; and the second, by the morphology of the lower canine and canine/premolar complex. Potentially derived features shared by callitrichines andSoriacebus, an older form from Patagonia, are convergent, however,Soriacebus is referred to a new higher taxon of the Tribe Pitheciini (Subfamily Pitheciinae), Subtribe Soriacebina, distinguished from its sister-group, the monophyletic Subtribe Pitheciina, by exhibiting a more primitive morphology than the characteristic sakiuakari dentition. The La VentaNeosaimiri, an alleged intermediate between callitrichines and other platyrrhines, is autapomorphically linked with squirrel monkeys, as is another cebine from the early Miocene,Dolichocebus, once classified as a callitrichine. The fossil record thus indicates that callitrichines were in existence by the middle Miocene, but their rarity as fossils reveals little of their broader phylogenetic ties or adaptive history. © 1989 Academic Press Limited.