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Trachypithecus, which currently contains 20 species divided into four groups, is the most speciose and geographically dispersed genus among Asian colobines. Despite several morphological and molecular studies, however, its evolutionary history and phylogeography remain poorly understood. Phayre’s langur (Trachypithecus phayrei) is one of the most widespread members of the genus, but details on its actual distribution and intraspecific taxonomy are limited and controversial. Thus, to elucidate the evolutionary history of Trachypithecus and to clarify the intraspecific taxonomy and distribution of T. phayrei, we sequenced 41 mitochondrial genomes from georeferenced fecal samples and museum specimens, including two holotypes. Phylogenetic analyses revealed a robustly supported phylogeny of Trachypithecus, suggesting that the T. pileatus group branched first, followed by the T. francoisi group, and the T. cristatus and T. obscurus groups most recently. The four species groups diverged from each other 4.5–3.1 million years ago (Ma), while speciation events within these groups occurred much more recently (1.6–0.3 Ma). Within T. phayrei, we found three clades that diverged 1.0–0.9 Ma, indicating the existence of three rather than two taxa. Following the phylogenetic species concept and based on genetic, morphological, and ecological differences, we elevate the T. phayrei subspecies to species level, describe a new species from central Myanmar, and refine the distribution of the three taxa. Overall, our study highlights the importance of museum specimens and provides new insights not only into the evolutionary history of T. phayrei but the entire Trachypithecus genus as well. [ABSTRACT FROM AUTHOR]

Twelve generic names have been ascribed to the New World tamarins but all are currently placed in just one: Saguinus Hoffmannsegg, 1807. Based on geographical distributions, morphology, and pelage patterns and coloration, they have been divided into six species groups: (1) nigricollis, (2) mystax, (3) midas, (4) inustus, (5) bicolor and (6) oedipus. Molecular phylogenetic studies have validated five of these groups; each are distinct clades. Saguinus inustus is embedded in the mystax group. Genetic studies show that tamarins are sister to all other callitrichids, diverging 15−13 Ma. The small-bodied nigricollis group diverged from the remaining, larger tamarins 11−8 Ma, and the mystax group diverged 7−6 Ma; these radiations are older than those of the marmosets ( Callithrix, Cebuella, Mico), which began to diversify 6−5 Ma. The oedipus group diverged from the midas and bicolor groups 5−4 Ma. We review recent taxonomic changes and summarize the history of the generic names. Taking into account the Late Miocene divergence time (11−8 Ma) between the large- and small-bodied tamarin lineages, the small size of the nigricollis group species when compared with other tamarins, and the sympatry of the nigricollis group species with the larger mystax group species, we argue that the nigricollis group be recognized as a distinct genus: Leontocebus Wagner, 1839. [ABSTRACT FROM AUTHOR]

Tamarins of the genus Saguinus, subfamily Callitrichinae, represent one of the most diverse primate radiations. So far, about 35 taxa have been described, but detailed information about their taxonomy and phylogeny is still lacking. To further elucidate the phylogenetic relationships and the biogeographic history within the genus, and to contribute to a more reliable classification of its taxa, we sequenced the complete mitochondrial cytochrome b gene and the hypervariable region I of the D-loop. Therefore, we mainly used fecal samples from wild tamarins collected during two expeditions to the Peruvian Amazon, an area of high tamarin diversity. Our data suggest that the numerous taxa of the S. nigricollis species group are derived from a common ancestor that separated from the other representatives of the genus ∼10 mya. Most taxa of the S. nigricollis group form monophyletic clusters, which mainly originated in a single rapid radiation ∼2.9 mya. S. fuscicollis and S. nigricollis appear as polyphyletic taxa, but we could identify various clusters, which are mainly consistent with differences in coat coloration. We could confirm most of the existing taxa as distinct entities and suggest species status for fuscicollis, illigeri, lagonotus, leucogenys, nigricollis, nigrifrons, tripartitus, and weddelli. Our genetic data do not support a separate status for melanoleucus and graellsi, but due to differences in fur coloration, we give them subspecies status. The species group most likely originated in western Amazonia and diversified during the decline of the Acre wetland and the formation of the Amazonian river system. Am J Phys Anthropol, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]