New data on sauropod palaeobiodiversity at the Jurassic‑Cretaceous transition of Spain (Burgos)
An article on a sauropod humerus recovered from the Torrelara site (Burgos) has just been published in the Journal Iberian of Geology. The authors of the study are Fidel Torcida Fernández-Baldor, director of the Dinosaur Museum and director of the dinosaur excavations of the Sierra de la Demanda and CAS, Pedro Huerta Hurtado of the Scientific Committee of the Dinosaur Museum, of the Archaeological and Paleontological Collective of Salas and from the University of Salamanca and José Ignacio Canudo Sanagustín from Grupo Aragosaurus ‑ IUCA, Paleontology, Faculty of Sciences, University of Zaragoza.
The present paper studies a humerus (MDS-VPCR, 214) recovered from the site of Valdepalazuelos-Tenadas del Carrascal (Burgos, Spain). Geologically, it is located at the base of the Rupelo Formation (Cameros Basin), which is Tithonian-Berriasian in age. This formation is interpreted as shallow lacustrine/palustrine deposits with low-gradient margins and periodic changes in the water level. MDS-VPCR, 214 is gracile and straight, and has a larger mediolateral expansion at its proximal end than at the distal end. The deltopectoral crest is well expanded anteroposteriorly and extends towards the midline of the shaft. The distal articular head has radial and ulnar condyles similar in degree of development and there is a narrow groove between them. The distal articular surface is not divided between the ulnar and radial condyles; this surface extends towards the anterior and posterior surfaces of the humerus. MDS-VPCR, 214 shows significant morphological differences with respect to the humeri of the Iberian sauropods of the Jurassic-Cretaceous transition such as the turiasaurians Losillasaurus, Zby and Turiasaurus, the basal macronarians Lourinhasaurus and Aragosaurus, and the titanosauriforms Lusotitan, Galvesaurus.A phylogenetic analysis of MDS-VPCR, 214 relates it to Titanosauriformes probably a basal brachiosaurid related with the english genus of Kimmeridgian Duriatitan. Therefore MDS-VPCR, 214 is assigned provisionally to aff. Duriatitan.