THERYA, 2016, Vol. 7 (3): 407-421 DOI: 10.12933/therya-16-412 ISSN 2007-3364 Distribución y estado actual del conocimiento del perezoso de dos dedos de Hofmann (Choloepus hofmanni) en Colombia, con comentarios sobre sus variaciones morfológicas externas Distribution and current state of knowledge of Hofmann’s two-toed sloth ( Choloepus hofmanni ) in Colombia, with comments on the variations of its external morphological traits Tinka Plese 1 *, Nicolás Reyes-Amaya 2 , Leyn Castro-Vásquez 3 , Sebasian Giraldo 1 , Orlando Feliciano 4 . 1 Fundación AIUNAU. Circular Primera, No. 73-20, Medellín, Colombia. E-mail: f.aiunau@gmail.com (TP), sgg148@gmail.com (SG). 2 Unidad Ejecutora Lillo (CONICET-FML). Miguel Lillo 251, San Miguel de Tucumán, Argentina. E-mail: nicolas.reyes2@gmail.com (NRA). 3 Universidad del Atlántico, Facultad de Ciencias Básicas, Programa de Biología. Barranquilla, Colombia. E-mail: leyncastro@gmail. com (LCV). 4 Fundación Bioandina Colombia (FBC). Guasca, Colombia. E-mail: orfelvet@hotmail.com (OF). * Corresponding author Hofmann’s two-toed sloth (Choloepus hofmanni) has been extensively studied since the 1940s in some countries across its distribution range. However, several aspects of its biology remain unexplored or have been described supericially. This study updated the geographic distribution of this sloth species in Colombia, describing external traits of specimens that inhabit diferent areas of the country. Additionally, a revision of the current state of knowledge of this species in Colombia was conducted, with a focus on the identiication of information gaps and the major threats afecting this species. An updated map of the distribution of C. hofmanni in Colombia was elaborated, including the distribution reported by IUCN, the records of specimens received in the Xenarthra center for rescue and rehabilitation (CRRX, for its acronym in Spanish; primary information), the wildlife care centers of the Autonomous Regional Corporations (CARs, for its acronym in Spanish), and records of biological collections available online (secondary information). CRRX specimens were examined externally, and the external morphological characteristics (skull and body shape; pelage color, length and density) were described. A comprehensive literature review was performed, compiling studies conducted over the last two decades on this species in Colombia, analyzing their respective contributions to its knowledge. The records obtained provide localities of occurrence for the species not previously recognized by IUCN, in 54 municipalities of 12 departments of Colombia. There are external morphological patterns deining lowland (interandean valleys and Caribbean region), highland (Colombian Andes) and Colombian Paciic populations. The biggest information gaps regard demography, distribution and genetics. The main threats identiied are habitat loss (infrastructure construction, forest clearance) and removal of specimen (illegal trade). The localities of occurrence obtained conirm the distribution of this species in areas previously suggested at the north and center of the Cordillera Occidental, Cordillera Central and Cauca River valley, besides the north, center and south of the Cordillera Oriental, Piedemonte Llanero, and the southern Magdalena River valley. The external revision of specimens from the CRRX shows that although it is impossible to derive clear taxonomic inferences from the evidence collected, pelage color, length and density are the most representative external traits that diferentiate lowland, highland and Paciic Colombian populations. The prioritization of issues such as the conservation status and threats in the investigation of this species in Colombia during the last twenty years have relegated key aspects such as demography, distribution, taxonomy and genetics, a fact that poses a challenge for the execution of proper management actions in the country. Key words: Choloepus hofmanni; conservation; distribution; population density. El perezoso de dos dedos de Hofmann (Choloepus hofmanni) ha sido ampliamente estudiado desde la década de 1940 en algunos países de su distribución. Sin embargo, aún son varios los aspectos de su biología que permanecen inexplorados o vagamente descritos. En el presente estudio se realiza una actualización de la distribución geográica de este perezoso en Colombia, describiendo caracteres externos de ejemplares para diferentes zonas del país. Adicionalmente se realiza un recuento del estado actual de su conocimiento en Colombia, con un enfoque dirigido hacia la identiicación de vacíos de información y sus principales amenazas. Se realizó un mapa actualizado de la distribución de C. hofmanni en Colombia, incluyendo la realizada por la UICN, los registros de ejemplares recibidos por el Centro de Rescate y Rehabilitación de Xenarthras (CRRX, información primaria), los centros de atención y valoración