Can molecular data place each neotropical monkey in its own branch?

Four different DNA datasets, representative of all extant neotropical prima te genera, were tandemly aligned, comprising some 6,763 base pairs (bp) wit h 2,086 variable characters and 674 informative sites. Maximum Parsimony, M aximum Likelihood and Neighbor-Joining analyses suggested three monophyleti c families (Atelidae, Pitheciidae and Cebidae) that emerged almost at the s ame time during primate radiation. Combined molecular data showed congruent branching inside the atelid clade, placing Alouatta as the most basal line age followed by Ateles and a more derived branch including Brachyteles and Lagothrix as sister groups. In the Pitheciidae, Callicebus was the most bas al lineage with respect to Pithecia and to the more derived sister groups ( Cacajao and Chiropotes). Conjoint analysis strongly supported the monophyly of the Cebidae, grouping Aotus, Cebus and Saimiri with the small callitric hines. Within callitrichines, Cebuella merged with Callithrix, Callimico ap peared as a sister group of Callithrix/Cebuella, Leontopitecus as a sister group of the previous clade, and Saguinus was the earliest callitrichine of fshoot. Two major points remained to be clarified in platyrrhine phylogeny: (i) the exact branching pattern of Aotus, Cebus, Saimiri and the callitric hines, and (ii), which two of these three families (Atelidae, Pitheciidae a nd Cebidae) are more closely related to one another.