Abstract Based on previous systematic studies of productid, rhynchonellid and spiriferid brachiopods from NW Sahara (Morocco and Algeria), we recognize three successive faunas near the Devonian–Carboniferous boundary. A ‘Lower Fauna’, late Famennian in age [IV(?)-V and lower VI(?) Zones], and an ‘Upper Fauna’, early Tournaisian in age, are present in southern Morocco (Assa, Akka, Zemoul areas) and in Algeria, Timimoun area. A third ‘Intermediate Fauna’, with few taxa, and differing according to the areas, is identified in southern Morocco. Northwards, in Tafilalt–Ma'der basins, rare brachiopods, found above a ‘Hangenberg Black Shale’ equivalent, are in spite of taxonomic differences related to the ‘Upper Fauna’. This important renewal of faunas could be in relation to the main lithological variations.