The fish supergroup Otophysi, known for their enhanced hearing, comprises two-thirds of living freshwater fish species. Previously, they were thought to have originated in freshwater before the breakup of the supercontinent Pangea, implying a nearly 80-million-year gap between the origin and oldest known fossil. However, the discovery of Acronichthys maccognoi — a newly-described freshwater otophysan species that lived during the Late Cretaceous...
