An unusual new sauropod dinosaur from the Late Cretaceous of Mongolia

Abstract

© 2020, © The Trustees of the Natural History Museum, London 2020. All rights reserved. A new sauropod, Abdarainurus barsboldi gen. et sp. nov., is described based on several anterior and one middle caudal vertebrae and chevrons from the Late Cretaceous Alagteeg Formation at Abdrant Nuru, northern Gobi Desert, Mongolia. The new taxon is characterized by 16 unique or rare characters of the caudal skeleton, including opisthocoelous centra, longitudinal ridges on the neural canal walls, postprezygapophyseal processes, a hypertrophied postspinal fossa, mediolaterally constricted neural spines, and a deep pocket-like spinodiapophyseal fossa covered laterally by high postzygodiapophyseal lamina. Our preferred phylogenetic analysis places Abdarainurus as a basal titanosaurian sauropod, but this result could be affected by inadequate knowledge of basal titanosaurs. The new taxon likely represents a highly specialized lineage of Asian macronarian sauropods that was unknown previously. http://zoobank.org/urn:lsid:zoobank.org:pub::87174FD4-0616-4BD6-9209-C40C0455D2DA.