First records of Casiornis rufus (Vieillot, 1816) (Aves, Tyrannidae) for the state of Rio Grande do Sul, southern Brazil

The Rufous Casiornis, Casiornis rufus (Vielliot, 1916), is widespread in central South America, reaching its southernmost distribution in northern Argentina and Uruguay. Here we present the first nine records of the species for Rio Grande do Sul state, southern Brazil. The records were documented with photographs and consisted mostly of lone individuals observed in riparian forests inserted in a matrix of grasslands and rice fields. The Rufous Casiornis apparently occurs in very low densities in the region. More observations are needed to elucidate its status of occurrence in Rio Grande do Sul.