Lower Cretaceous ammonites from the Neuquén Basin, Argentina: A new heteromorph fauna from the uppermost Agrio Formation

► A completely new heteromorph ammonite fauna discovered in Argentina. ► It occurs in the topmost beds of the Agrio Formation over the northern Neuquén Basin. ► Three genera are identified, Sabaudiella, Hamulinites? and Curacoites, the last new. ► The ammonite fauna is dated as encompassing the Hautevian-Barremian boundary.