 With recent molecular evidence, "Lacantunia" has been shown to be the sister group to Claroteidae, an African catfish family.It probably diverged from the claroteids in the Late Cretaceous between 75 and 90 mya.The generic name of the fish reflects its distribution in the Río Lacantún drainage, flowing through the Montes Azules and Selva Lacandona Biosphere Reserves in México into that country's largest river, the Río Usumacinta.