Aylacostoma

[2] Some species in this genus used to live in areas of white water in the Yacyretá Rapids, Paraná River, feeding on the algae that grow attached to the rocks on the bottom.

[citation needed] Aylacostoma is a parthenogenic species: the population consists of only females, which increase in number by asexual reproduction.

The females give birth to a small number of larvae, no more than three, that are born very well developed, so they have the physical strength needed to attach to a rock and resist the strong current.

[citation needed] With the building in 1993 of the Yacyretá Dam, almost all the suitable habitat for Aylacostoma living in this region was flooded.

[3][4] The captive populations of the last two species are jointly managed by the National University of Misiones and Bernardino Rivadavia Natural Sciences Museum.