Re-examination of Arambourg’s collection of Messinian fossil fishes from Oran and the Chelif Basin, Western Algeria and the study of Dr Léopold Geslin’s material collected at Oran-Ravin Blanc (Gambetta-Saint-Eugène) old quarry has allowed an improvement of the paleoecological interpretation of the fish faunas from this region. The importance of upwellings was demonstrated in this locality because myctophids, which have a mesopelagic way of life, are by far the dominant components (62%). At Sig, their influence was less important, although myctophids are still relatively abundant (29%). In contrast, the fish fauna from Oran-Raz-el-Aïn is indicative of a shallow water nearshore environment in which neritic, littoral and pelagic fishes where living together, whereas the occurrence of rather scarce myctophids suggests that a deep sea was present in the vicinity. The study of the fish fauna from Sidi Brahim is based on an abundant material in which more taxa were identified. However, a detailed geological field work would be useful for a better understanding of its paleoecological significance. The same remarks can be applied to the locality called Renault (Sidi M’hamed Ben Ali) which was not sufficiently sampled.
Teleostean fishes, Oran, Algeria, Messinian, paleobiodiversity, paleoenvironments.