Morphology, Taxonomic Status and Affinities of the Lion Tamarins, Leontopithecus (Callitrichinae, Cebidae)

Abstract

A survey of craniodental variability of the three allopatric populations of Leontopithecus reveals that they are morphologically heterogeneous and individually distinctive, with a nonclinal distribution of characters and pattern similarities. These observations correspond with their better known, starkly different coat coloration, and imply important ecological-adaptive differences. Leontopithecus chrysomelas contrasts markedly in its robust physique, relatively massive and anatomically modified incisors, comparatively small cheek teeth and unique cranial shape. Leontopithecus rosalia is smallest and most gracile, with a highly abbreviated premaxilla and reduced anterior dentition. Leontopithecus chrysopygus is quite the largest in most bodily and cranial dimensions yet is more similar to Leontopithecus rosalia in anterior tooth size and proportions, and has a massively built face. Phyletically, Leontopithecus is most closely related to Callithrix (incl. Cebuella) among the callitrichines. Protection of their habitats is urged for there are three times as many species of endangered Lion Tamarins as we had thought.