Presentamos un caso de desorden cromático observado en un ejemplar de Trachops cirrhosus proveniente de bosques de tierras bajas de la Amazonía ecuatoriana. Durante el trabajo de campo, seis individuos de esta especie fueron capturados con redes de niebla en un hábitat intervenido, de los cuales, un ejemplar macho juvenil fue distinguible del resto de individuos debido a la presencia manchas blanquecinas en la región ventral, en el pecho y abdomen. Discutimos sobre los reportes previos de este tipo de trastornos pigmentarios en murciélagos de Ecuador, y en el Neotrópico, documentando el primer registro de esta especie con esta condición para el país.

Basic diversity studies of small non-volant mammals are scarce in western Ecuador, evidencing a knowledge gap regarding the mammalian fauna in the region. These organisms play key roles in important ecological processes and may be affected by several anthropogenic factors. Herein we report the results of a rapid assessment of marsupials and rodents of Bosque Protector Cerro Blanco (Guayas province), a fragment of dry forest surrounded by urban development. Between October 2016 and March 2017, we trapped rodents and marsupials with Sherman and Tomahawk live traps; also, we conducted direct observations and searched for skeletal remains. We recorded nine species of small non-volant mammals, seven native and two invasive. The marsupial Marmosa simonsi was the most frequently captured species. We reported three previously unrecorded species for this reserve: Sigmodon peruanus, Aegialomys baroni, and Rhipidomys latimanus. We recommend continued monitoring of the mammalian fauna of Cerro Blanco using alternative techniques such as pitfall traps, canopy live traps, and analysis of owl pellets. These efforts will permit a better understanding of the marsupial and rodent assemblage in this important site for biodiversity conservation in coastal Ecuador, a region that unfortunately faces intense human pressure.