[2] This fish is found in Panama, Venezuela, and Colombia, where it lives in shallow waters in the basins of the Lebrija, Magdalena, Cauca and other rivers.

This fish is a very tolerant species, able to withstand considerable variations in temperature and salinity, as well as low levels of oxygen.

[2] An omnivore, P. caucana feeds on algae, on mosquito larvae and on insects that fall onto the water surface.

[2] Proposals have been made to use this species, as well as the closely related guppy (Poecilia reticulata),[5] in biological pest control of mosquitoes.

[6] The Cauca molly is a livebearer; the female produces a batch of ten to twenty-five live young after a gestation period of about four weeks.