Molecular phylogeny of New World primates (Platyrrhini) based on beta(2)-microglobulin DNA sequences

Neotropical primates, traditionally grouped in the infraorder Platyrrhini, comprise 16 extant genera. Cladistic analyses based on morphological charac teristics and molecular data resulted in topologic arrangements depicting d isparate phylogenetic relationships, indicating that the evolution of gross morphological characteristics and molecular traits is not necessarily cong ruent. Here we present a phylogenetic arrangement for all neotropical prima te genera obtained from DNA sequence analyses of the beta(2)-microglobulin gene. Parsimony, distance, and maximum likelihood analyses favored two fami lies, Atelidae and Cebidae, each containing 8 genera. Atelids were resolved into atelines and pitheciines. The well-supported ateline clade branched i nto alouattine (Alouatta) and ateline (Ateles, Lagothrix, Brachyteles) clad es, In turn, within the Ateline clade, Lagothrix and Brachyteles were well- supported sister groups. The pitheciines branched into well-supported calli cebine (Callicebus) and pitheciine (Pithecia, Cacajao, Chiropotes) clades. In turn, within the pitheciine clade, Cacajao and Chiropotes were well-supp orted sister groups. The cebids branched into callitrichine (Saguinus, Leon topithecus, Callimico, Callithrix-Cebuella), cebine (Cebus, Saimiri), and a otine (Aotus) clades. While the callitrichine clade and the groupings of sp ecies and genera within this clade were all well supported, the cebine clad e received only modest support, and the position of Aotus could not be clea rly established. Cladistic analyses favored the proposition of 15 rather th an 16 extant genera by including Cebuella pygmaea in the genus Callithrix a s the sister group of the Callithrix argentata species group. These analyse s also favored the sister grouping of Callimico with Callithrix and then of Leontopithecus with the Callithrix-Callimico clade. (C) 1999 Academic Pres s.