The Devonian of the Hodh area (Islamic Republic of Mauritania): Paleontology and stratigraphy

Paleontological study of 16 samples from four sections through the Silurian-Devonian marine deposits of the Hodh region establishes the development of the Middle Devonìan and adds to our knowledge of the Paleozoic sequence in the West African platform. Above Silurian deposits locally dated by graptolites from the Llandovery, Devonian shales yield an abundant although low diversity benthic fauna, which is assigned to a Givetian age. The brachiopod fauna shows strong affinity with the NE Americas Realm. Two new species are described, Arcuaminetes deynouxi and Eleutherokomma monodi. The revision of the Devonian fauna of the Hodh area supports: 1) the apparent lack of Lower Devonian deposits; 2) the Givetian age of the Devonian succession; and 3) the strong eastern Americas Realm affinity of the fauna, as previously established for the Mauritanian Adrar area.