Abstract
During a taxonomic revision of the genus Croton from the Pampas grasslands, some necessary taxonomic adjustments were identified and are here presented. The study was based on new collections, field work and analyses of protologues and type specimens. We treat C. allemii as a synonym of C. triqueter, C. stenotrichus as a synonym of C. hilarii, and we designate a lectotype for C. stenotrichus. Croton lombardianus is newly reported for Brazil and C. macrobothrys as a new record for the Atlantic Moist Forest in the state of Rio Grande do Sul. Updated information on the geographic distributions of these species is also provided.