Article révisé par les pairs
Résumé : Fifty ostracod species, of which 44 are figured herein, have been identified in the Givetian of the Ain Khira section located in the NW Meseta of Morocco. These species belong to the Eifelian ecotype and are indicative of a well oxygenated shallow marine environment near fair-weather wave base and temporary, in the upper part of the section, near storm wave base. Assemblages rich in Coeloenellina POLENOVA, 1952. are indicative of semi-restricted water conditions on the inner ramp. The study of ostracods don't prove the existence of lagoonal water conditions unlike the sedimentological study. However the occurrence of marine ostracods in lagoonal environments can be explained by sea incursions during exceptional events as storms or spring tides. The occurrence of Polyzygia beckmanni beckmanni KRÖMMELBEIN, 1954, in the upper part of the section proves that a large part of the Givetian is present at Ain Khira.