It is being reported, for the first time, in South Brazil and South cone of South America, a rust occurrence on leaves of Black wattle (Acacia mearnsii). This rust has been morphologically identified as the uredinial state of Uromycladium alpinum. The occurrence of this rust on the black wattle plantations of Rio Grande do Sul State has brought light damage. Until now, there are none report about this rust on A. mearnsii in South America.
