Ololygon cardosoi is a species of frog in the family Hylidae. The specific name cardosoi honors Adão José Cardoso, a Brazilian herpetologist. It is endemic to Brazil. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane forests, and rivers. It is threatened by habitat loss. References cardosoi Endemic fauna of Brazil Amphibians of Brazil Amphibians described in 1991 Taxonomy articles created by Polbot Taxobox binomials not recognized by IUCN