The bee genus Caupolicana Spinola is most diverse in temperate South America, and poorly represented in Brazil, where only two species (C. gaullei Vachal and C. lugubris Smith) were hitherto known. Here, a third species of the genus (C. rupestris Zama, Ferrari, Coelho and Silveira sp. nov.) in that country, is being described, from the ‘rocky fields’ of Minas Gerais state. Additionally, the male terminalia and the female of C. gaullei are described for the first time. A key to the Brazilian species of Caupolicana is also given.