Les sources du Moyen Atlas et de Rif (Maroc): Faunistique (description de deux espèces nouvelles de Trichoptères), écologie, intérêt biogéographique

Seven springs in the Middle Atlas and five in the Rif have been studied. These show a great diversity of crenal habitats: water temperature ranges from 8.7° to 21°C, and the flow from 1 l/s to 1,800 l/s. Based on hydrologic and thermic characteristics, a spring typology is provided. The invertebrate community consists of 60 species, among which 4, found in the Rif, are new to science: Protonemura sp. (Plecoptera), Obuchovia sp. (Diptera, Simuliidae), Rhyacophila fonticola n. sp., and Philopotamus ketama n. sp. (Trichoptera). The new Trichoptera are both described. Two rare endemic species (the planarian Acromyadenium maroccanum and the coleopteran Elmis atlantis) have been found in a cold-water spring in the Middle Atlas; two black-fly species ( Cnetha carthusiensis and Simulium lamachei), new to North Africa, have been collected in a cold-water spring in the Rif. The cold-water spring community shows a high rate of endemism. Seven endemic cold-stenothermous species constitute a most characteristic crenon fauna in northern Morocco. The fauna of warmer springs (18° ≤ temp. ≤ 21°C) contains potamophilous and thermophilous species, a few of them belonging to the Ethiopian fauna. A comparative study of spring and rhithric communities of Morocco shows that, in the Middle Atlas and the Rif, cold-water springs became refugia for cold-stenothermous, west-palaearctic species; in the past, these species occupied a larger territory which has been reduced after recent climatic and hydrologic changes.