The Upper Pliocene Avifauna of Ahl al Oughlam, Morocco. Systematics and Biogeography
Résumé
The locality of Ahl at Oughlam, situated at the southeastern limit of the city of Casablanca (Morocco) at about 34 degrees north, is dated by the biochronology of its rich mammalian fauna to about 2.5 Ma. At the present time it is 6.5 km from the Atlantic Ocean but it was on the seashore when the fossil material was deposited. Among the seabirds are Phoebastria anglica, Phoebastria sp. cf. P. albatrus, Phoebastria sp. cf. P. nigripes, Pelagornis mauretanicus, Calonectris sp. cf. C. diomedea, Morus peninsularis, Morus sp. cf. M. bassanus, Catharacta sp. cf. C. skua, Alca ausonia. Among the landbirds are Struthio asiaticus, Geronticus olsoni n.sp., several anseriforms, Plioperdix africana n.sp., several otidids, Agapornis atlanticus n.sp., Tyto balearica, T. alba, Surnia robusta, and a few Passeriformes. The Recent species of albatrosses Phoebastria albatrus and P. nigripes live in the North Pacific but were also present in the North Atlantic until the Middle Pleistocene. The marine avifauna shows many similarities with that of the Yorktown Formation, in North Carolina. Unlike the mammals, which include many genera in common with the African faunas, the landbirds have more affinities with the Palaearctic region than with the Ethiopian region. They include several extinct genera or species that have been described, or identified, in the Pliocene of the Palaearctic region. The terrestrial avifauna is very different from all those that have been described from the upper Miocene and Pliocene of Africa