Austrolebias is a genus of killifish in the family Rivulidae.

These annual killifish live in temporary pools, swamps and streams in the Río de la Plata, Patos–Mirim and Mamoré basins in South America.

[3][4] Most species are small, less than 10 cm (3.9 in) in total length, but a few reach 15–22 cm (5.9–8.7 in), making them some of the largest killifish (only a few Fundulus, Moema and Orestias reach a similar or larger size).

[3][5] There are currently 46 recognized species in this genus:[5]