Osteology of the Late Cretaceous Argentinean sauropod dinosaur Mendozasaurus neguyelap: Implications for basal titanosaur relationships
| Autor: | Stephen John Poropat, Bernardo J. González Riga, Leonardo Daniel Ortiz David, Juan Pedro Coria, Philip D. Mannion |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
0106 biological sciences
Titanosaur 01 natural sciences Ciencias de la Tierra y relacionadas con el Medio Ambiente Mendozasaurus Neuquen Group TITANOSAURIFORMES Neuquén Group Lognkosauria BONITASAURA-SALGADOI Gondwana biology Sierra Barrosa Formation NORTH-AMERICA Bauru Group Cretaceous PATAGONIA SP-NOV Life Sciences & Biomedicine CIENCIAS NATURALES Y EXACTAS SIERRA BARROSA FORMATION 010506 paleontology MENDOZA GIANT SAUROPOD BAURU GROUP 0608 Zoology CENTRAL INDIA 010603 evolutionary biology NEUQUÉN GROUP EVOLUTIONARY HISTORY MESOZOIC Lithostrotia PHYLOGENETIC-RELATIONSHIPS GONDWANA Mendoza LITHOSTROTIA Ecology Evolution Behavior and Systematics 0105 earth and related environmental sciences Evolutionary Biology Science & Technology Osteology LOGNKOSAURIA biology.organism_classification Archaeology Titanosauriformes Animal Science and Zoology Meteorología y Ciencias Atmosféricas Zoology Mesozoic NEUQUEN BASIN |
| Popis: | The titanosaurian sauropod dinosaur Mendozasaurus neguyelap is represented by several partial skeletons from a single locality within the Coniacian (lower Upper Cretaceous) Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina. A detailed revision of Mendozasaurus, including previously undocumented remains from the holotype site, allows us to more firmly establish its position within Titanosauria, as well as enabling an emended diagnosis of this taxon. Autapomorphies include: (1) middle and posterior cervical vertebrae with tall and transversely expanded neural spines that are wider than the centra, formed laterally by spinodiapophyseal laminae that are not connected with the pre- or postzygapophyses; (2) anterior caudal vertebrae (excluding anteriormost) with ventrolateral ridge-like expansion of prezygapophyses; and (3) humerus with divided lateral distal condyle on anterior surface. New remains demonstrate that the presacral vertebrae of Mendozasaurus were not unusually short anteroposteriorly, with this compression instead resulting from taphonomic crushing. Comparative studies of articulated pedes of other taxa allow us to interpret that the pedal formula of Mendozasaurus was 2-2-2-2-0, based on disarticulated bones that form a right hind foot. Mendozasaurus was incorporated into an expanded version of a titanosauriform-focussed phylogenetic data matrix, along with several other contemporaneous South American titanosaurs. The resultant data matrix comprises 84 taxa scored for 423 characters, and our phylogenetic analysis recovers Mendozasaurus as the most basal member of a diverse Lognkosauria, including Futalognkosaurus and the gigantic titanosaurs Argentinosaurus, Notocolossus, Patagotitan and Puertasaurus. Lognkosauria forms a clade with Rinconsauria (Muyelensaurus + Rinconsaurus), with Epachthosaurus and Pitekunsaurus recovered at the base of this grouping. A basal lithostrotian position for this South American clade is well supported, contrasting with some analyses that have placed these taxa outside of Lithostrotia or closer to Saltasauridae. The sister clade to this South American group is composed of an array of near-global taxa and supports the hypothesis that most titanosaurian clades were widespread by the Early-middle Cretaceous. Fil: Gonzalez Riga, Bernardo Javier. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina Fil: Mannion, Philip D.. Imperial College London; Reino Unido Fil: Poropat, Stephen John. Swinburne University of Technology; Australia. Museum of Natural History; Australia Fil: Ortiz David, Leonardo Daniel. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina Fil: Coria, Juan Pedro. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina |
| Databáze: | OpenAIRE |
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