Cyrnaonyx is an extinct genus of Lutrinae, otters from the Pleistocene. It was originally described by Helbing based on materials from France and he also attributed material from Corse to it. The latter appeared to belong to another species and genus, Algarolutra majori. The only species of Cyrnaonyx is C. antiqua. It is known from the Pleistocene (Holsteinian to Eemian/Weichselian) of Europe: France, Germany, Netherlands, Southern England and probably Italy.