Microvertebrate fauna from Gadoufaoua (Niger, Aptian, Early Cretaceous)

• Published in: Comptes Rendus Palevol
• Main Authors: Pochat-Cottilloux, Yohan, Allain, Ronan, Lasseron, Maxime
• Other Authors: Centre de Recherche en Paléontologie - Paris (CR2P), Muséum national d'Histoire naturelle (MNHN)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: Microvertebrates; Cretaceous; Niger; Gadoufaoua; Africa; palaeobiogeography; [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology; South Atlantic Ocean
• Online Access: https://hal.sorbonne-universite.fr/hal-03924689; https://hal.sorbonne-universite.fr/hal-03924689/document; https://hal.sorbonne-universite.fr/hal-03924689/file/final.pdf; https://doi.org/10.5852/cr-palevol2022v21a41

International audience In the palaeogeographical context of the opening of the South Atlantic Ocean at the end of the Early Cretaceous, we document here the first microvertebrate fauna recorded from the Aptian deposits of Gadoufaoua, Niger. A systematic study of the fauna has resulted in a significant expansion of the existing faunal list and increase our knowledge of the palaeobiodiversity of the Gadoufaoua fossil site. Some taxa were previously recorded (lungfishes, crocodilians, chelonians, etc.), but several new taxa are described here for the first time, including the first occurrence of a stem-boreosphenidan mammal in Africa for this time-interval. In addition, chondrichthyans, pterosaurs and lissamphibians are documented. The analysis of taxonomic diversity and preservation of the fossils confirms a floodplain depositional environment (more precisely channel-type), in a higher velocity flow regime than previously thought based on studies of the macrofauna. To confirm the depositional environment inferred by the state of preservation of the fossils, a preliminary comparison with the fauna of similar age from the Santana Formation (Brazil) has been undertaken. The hypothesis of a communication between Africa and South America during the Aptian, as had already been demonstrated based on studies of the macrofauna, is strengthened.