A new annual fish of the genus (Cyprinodontiformes: Rivulidae) from Rio Camaquã basin, Laguna dos Patos system, Brazilian Pampa.

A new species of Austrolebias is described from the middle course of the Rio Camaquã, Laguna dos Patos system, Rio Grande do Sul, Brazil. The new species belongs to the Austrolebias alexandri species group, which is distinguished from the remaining congeners by the presence of a dark gray pectoral fin with bright blue iridescence in males. The new species is distinguished from all remaining species of the A.

First record of blackfin pearlfish (Regan, 1912 (Cyprinodontiformes, Cynolebiidae) from Brazil.

Austrolebias Costa is a genus of annual fish inhabiting temporary wetlands in the Chaco-Pampasic region of southern Brazil, Uruguay, Paraguay, Bolivia and Argentina (Costa, 2006, Nielsen & Pillet, 2015, Alonso et al., 2016). Currently, about 45 species of Austrolebias are known (Costa, 2006, Volcan et al.