Colombian Lagothrix: Analysis of their phenotypes and taxonomy

Abstract

Colombian Lagothrix are phenotypically very complex and a clear diagnosis of the two taxa (that classically have been recognized for the country) does not exist. The characteristics used to define one taxon are often found in the other taxon. Only the Lagothrix lugens of the Central Cordillera of the Andes is clearly defined and different from all other populations despite the holotypic description. Lagothrix from the Eastern Cordillera, although generally darker than those found in the greater part of Amazonia (called lagothricha), have many characteristics that can be found also in lagothricha, such as coronal stripe and agouti back and forearms, while some lagothricha are also dark brown and gray like the majority of lugens of the Eastern Cordillera. Since the described taxa are not clearly distinct from each other, it seems more correct to see them as subspecies of a species L. Lagothricha, which often intergrade with one another. Two other subspecies have recently been described from the east of the Eastern Cordillera, although it is not clear whether these newly defined subspecies include other populations of the former lugens from the east of the Andes. Populations called lagothricha and lugens seem to be made up of a mosaic of phenotypes with no clines. Genetic information supports the view of a polytypic, broadly distributed species, L. Lagothricha with various distinctive populations, although further analysis might force us to abandon the subspecies of L. Lagothricha in Colombia altogether.