For the first time, Glyptograptus (Glyptograptus ?) ojsuensis KOREN & MIKHAILOVA of Ashgillian age is detected on the African continent in the Chirfa area (Djado, Republic of Niger). This occurrence allows a precise dating of the Chirfa Formation to be made and underlines the complexity of the paleogeography near the Ordovician-Silurian boundary of Gondwana, the reconstitution of which should not be influenced by the positions of the existing outcrops.