A new karyotype of an endangered primate species (Callicebus personatus) from the Brazilian Atlantic forests.

The genus Callicebus has 28 species arranged in five groups: donacophilus, torquatus, moloch, cupreus and personatus. The personatus group occurs in the Brazilian Atlantic forests where it is isolated from the other Callicebus groups. The present paper is the first report on the karyotype of Callicebuspersonatus. We compared the karyotypes of C. personatus and C. nigrifrons utilizing the following classic banding techniques: G-, C-, NOR banding, G/C- and G/NOR sequential banding. The karyotype of C. personatus has 2n=44, while C. nigrifrons presented 2n=42. Both the species diverge in the diploid number in consequence of a rearrangement type centric fusion/fission. Our results support personatus as a valid group and the specific status for C. personatus and C. nigrifrons.