Osteology of Ornithopod Macrogryphosaurus gondwanicus (Dinosauria, Ornithischia) from the Upper Cretaceous of Patagonia, Argentina
Registro en:
Rozadilla, S., Cruzado Caballero, P., & Calvo, J. O. (2020). Osteology of Ornithopod Macrogryphosaurus gondwanicus (Dinosauria, Ornithischia) from the Upper Cretaceous of Patagonia, Argentina. Cretaceous Research; 108; 104311.
0195-6671
Autor
Rozadilla, Sebastián
Cruzado Caballero, Penélope
Calvo, Jorge O.
Institución
Resumen
Fil: Rozadilla, Sebastián. Laboratorio de Anatomía Comparada y Evolución de Los Vertebrados, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina. Fil: Cruzado Caballero, Penélope. CONICET e Instituto de Investigación en Paleobiología y Geología, Sede Alto Valle-Valle Medio-Universidad Nacional de Río Negro; Argentina. Fil: Calvo, Jorge O. Grupo de Transferencia Proyecto Dino. Facultad de Ingeniería, Universidad Nacional del Comahue. Parque Natural Geo-Paleontologico Proyecto Dino; Argentina. Fil: Cruzado Caballero, Penélope. Universidad Nacional de Río Negro. Instituto de Investigación en Paleobiología y Geología. Río Negro, Argentina. Macrogryphosaurus gondwanicus is the largest Elasmaria (Dinosauria, Ornithischia) known up to the date,
from the Upper Cretaceous of Patagonia. The present contribution provides a detailed description of
Macrogryphosaurus anatomy based on the holotype and only known specimen. This dinosaur presents
several unique features along its vertebral column that distinguishes it from other ornithopods: the neck
is notably elongated by the acquisition of an additional cervical vertebra, having 10 cervical plus 14 dorsal
vertebrae, being the number of dorsals minor than in other taxa, which usually have 16. This implies that
Macrogryphosaurus represents a new ornithopod morphotype, with long neck and short thorax. Moreover, three autapomorphies are here added to the original diagnosis of Macrogryphosaurus: presence of
poorly developed diapophyses in the cervical vertebrae, anterior and posterior processes on the boatshaped haemal arches, and a pubic foot in the postpubic process. The dorsoventral length of haemal
arches indicate the ventral limit of the M. caudofemoralis longus and their posterior tapering so as the
dorsal limit of the M. ilio-ischiocaudalis and its posterior ascension and dominance in the posterior-most
portion of tail, resembling to the tail of some coelurosaur dinosaurs true -