Leucism in a Brazilian guinea pig Cavia aperea Erxleben, 1777 population

Abstract

Fur coloration serves several functions, including crypsis or background matching, an important feature to reduce predation. A dimorphic population, with rare light-colored guinea pigs is reported here at Colonia Pellegrini, Corrientes, Argentina. In May 2025, two Brazilian guinea pigs separated by a distance of 900-1000 m were observed grazing alongside normal-colored individuals. Multiple observations of this light morph have been consistently recorded since 2008 by a local resident. Although the frequency of the light morph in this population remains low, its persistent and widespread presence suggests that it has not experienced extremely high selection pressure.