Resumen
Ammonites of the genus Santafecites Etayo-Serna and subgenus Olcostephanus (Viluceras) Aguirre-Urreta and Rawson are described for the first time from Chile. The succession of Olcostephaninae from the Chañarcillo Basin of northern Chile is described in the light of new collections and revision of historical material. The occurrence of mixed Andean and Mediterranean faunas supports the correlations proposed with the ammonite scales of the Neuquén Basin and the Mediterranean Province.