Sciurus aureogaster Cuvier, 1829 is a sciurid commonly called the red-bellied squirrel. It is a medium-bodied tree squirrel quite variable in color throughout its geographic distribution; partial and complete melanism are common. One of 28 species in the genus, S. aureogaster is endemic to Mexico and Guatemala, and introduced to the Florida Keys, United States. S. aureogaster inhabits a wide variety of ecosystems and plant communities, is diurnal, arboreal, and uses leaf nests and tree cavities for nesting. S. aureogaster feeds primarily on acorns (Quercus) and pine (Pinus) seeds throughout most of its distribution, but individuals are known to damage corn and other plantation crops including cacao. Litter size ranges between 1 and 4 young. S. aureogaster is listed as “Least Concern” by the International Union for Conservation of Nature and Natural Resources.