Velafrons

''Velafrons'' (meaning "sailed forehead") is a genus of lambeosaurine hadrosaurid dinosaur from the Late Cretaceous of Mexico. It is known from a mostly complete skull and partial skeleton of a juvenile individual, with a bony crest on the forehead. Its fossils were found in the late Campanian-age Cerro del Pueblo Formation (about 72 million years oldLoewen, M.A., Sampson, S.D., Lund, E.K., Farke, A.A., Aguillón-Martínez, M.C., de Leon, C.A., Rodríguez-de la Rosa, R.A., Getty, M.A., Eberth, D.A., 2010, "Horned Dinosaurs (Ornithischia: Ceratopsidae) from the Upper Cretaceous (Campanian) Cerro del Pueblo Formation, Coahuila, Mexico", In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), ''New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium'', Indiana University Press, 656 pp.), near Rincon Colorado, Coahuila, Mexico. The type specimen is CPC-59, and the type species is ''V. coahuilensis''.

History of discovery

Largescale paleontological expeditions of the Cerro del Pueblo Formation in Coahuila began in 1986 with an expedition by the Royal Ontario Museum, which focused on a hadrosaurid bonebed near Presa de San Antonio. Subsequently, Dinamation International Society established multiple quarries around Rincon Colorado, including quarry 7A excavated from 1992 to 2001 where a mostly complete skeleton lacking a skull was found. In 2002 excavations of quarry 7A were restarted by the Utah Museum of Natural History, Royal Tyrrell Museum of Palaeontology and Museo del Desierto, where a disarticulated skull and partial skeleton was found within a calcareous grey mudstone by Hernández-Rivera. From magnetostratigraphy, the Cerro de Pueblo Formation is around 73.5 million years old, with the skeleton from around above the base of the formation. The skeleton and skull, CPC-59, was described in 2007 by American paleontologist Terry Gates and colleagues as the holotype of the new taxon ''Velafrons coahuilensis'', the first new genus of lambeosaurine from North America in over 70 years. The genus name combines the Spanish word ''vela'' and Latin word ''frons'' as "sailed forehead" in reference to the cranial crest, while the species name means "from Coahuila".

Despite being one of the most complete hadrosaurs from Mexico, ''Velafrons'' remains only partially described, with its postcranial skeleton being undescribed. Gates and colleagues interpreted ''Velafrons'' to be a subadult individual based on absolute size and the crest anatomy, comparing it most favourably with the ''Corythosaurus'' specimen CMN 34825. As that specimen is only about 60% of the full adult size of ''Corythosaurus'', that could suggest that ''Velafrons'' would be able to attain much larger sizes than its only known skeleton indicates.

Description

''Velafrons'' was most similar to young specimens of ''Corythosaurus'' and ''Hypacrosaurus'', and was found to be a corythosaurin in the phylogenetic analysis performed by Gates and colleagues in their description of the genus. The skull was large in comparison to skulls from other genera at a similar growth stage, so the crest may have been small in adults or followed a different growth pattern, or it may be that adult ''Velafrons'' were also larger than adults of other lambeosaurine genera. Unusually large size is also seen in the Mexican hadrosaurids ''Kritosaurus'' sp. and '' Magnapaulia laticaudus''. As a hadrosaurid, ''Velafrons'' would have been a herbivore. The animal is known from several disarticulated remains, those being certain cervical vertebrae and a disarticulated skull.

References

{{Taxonbar, from=Q134733

Lambeosaurinae
Dinosaur genera
Campanian dinosaurs
Taxa named by Scott D. Sampson
Taxa named by Lindsay Zanno
Taxa named by James I. Kirkland
Fossil taxa described in 2007
Dinosaurs of Mexico