Earliest known lepisosteoid extends the range of anatomically modern gars to the Late Jurassic

• Published in: Scientific Reports
• Main Authors: Brito, Paulo, Alvarado-Ortega, Jesus, Meunier, François J.
• Other Authors: Universidade do Estado do Rio de Janeiro Brasil = Rio de Janeiro State University Brazil = Université d'État de Rio de Janeiro Brésil (UERJ), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology; [SDV.BID]Life Sciences [q-bio]/Biodiversity; Antarc*; Antarctica
• Online Access: https://hal.sorbonne-universite.fr/hal-01678588; https://hal.sorbonne-universite.fr/hal-01678588/document; https://hal.sorbonne-universite.fr/hal-01678588/file/s41598-017-17984-w.pdf; https://doi.org/10.1038/s41598-017-17984-w

International audience Lepisosteoids are known for their evolutionary conservatism, and their body plan can be traced at least as far back as the Early Cretaceous, by which point two families had diverged: Lepisosteidae, known since the Late Cretaceous and including all living species and various fossils from all continents, except Antarctica and Australia, and Obaichthyidae, restricted to the Cretaceous of northeastern Brazil and Morocco. Until now, the oldest known lepisosteoids were the obaichthyids, which show general neopterygian features lost or transformed in lepisosteids. Here we describe the earliest known lepisosteoid (Nhanulepisosteus mexicanus gen. and sp. nov.) from the Upper Jurassic (Kimmeridgian – about 157 Myr), of the Tlaxiaco Basin, Mexico. The new taxon is based on disarticulated cranial pieces, preserved three-dimensionally, as well as on scales. Nhanulepisosteus is recovered as the sister taxon of the rest of the Lepisosteidae. This extends the chronological range of lepisosteoids by about 46 Myr and of the lepisosteids by about 57 Myr, and fills a major morphological gap in current understanding the early diversification of this group.