Presence du genre Gagaria (Echinide regulier Temnopleuride) dans l'Eocene moyen de la vallee du Senegal

The genus Gagaria, known in the Eocene of the Indian peninsula, is noted for the first time in the lower Lutetian of the Senegal-Mauritania sedimentary basin. It is represented by G. foutatoroensis n. sp., whose mode of occurrence is defined. Comments on the associated fauna and on the environment where this species must have lived are given. G. foutatoroensis is interesting because of its relationships with several genera (Thylechinus, Orthechinus, Triplacidia) existing at the same time, especially in Senegal and Egypt.