[D] Arenysaurus ardevoli [sG] [T]
Pereda-Suberbiola, Canudo, Cruzado-Caballero, Barco, López-Martínez, Oms & Ruíz-Omeñaca 2009
Cretaceous Late Maastrichtian
Ornithischia Ornithopoda Hadrosauridae Lambeosaurinae
Fossilsite: Tremp Formation, Blasi 3 site in Aren, Spain
Abstract: A new hadrosaurid dinosaur, Arenysaurus ardevoli gen. et sp. nov., from the Late Maastrichtian of Aren (Blasi 3 site of Arén, Huesca, South-central Pyrenees) is described on the basis of a partial, articulated skull, mandibular remains and postcranial elements, including vertebrae, girdle and limb bones. Arenysaurus is characterized by having a very prominent frontal dome; nearly vertical prequadratic (squamosal) and jugal (postorbital) processes, and deltopectoral crest of the humerus oriented anteriorly. Moreover, it possesses a unique combination of characters: short frontal (length/width approximately 0.5); midline ridge of parietal at level of the postorbitalsquamosal bar; parietal excluded from the occiput; squamosal low above the cotyloid cavity. A phylogenetical analysis indicates that Arenysaurus is a rather basal member of Lambeosaurinae and the sister-taxon to Amurosaurus and the Corythosaurini-Parasaurolophini clade. The phylogenetic and biogeographical relationships of Arenysaurus and other lambeosaurines suggest a palaeogeographical connection between Asia and Europe during the Late Cretaceous
Etymology: From Aren (Areny de Noguera in Catalonian language), the village of Huesca province (Spain) located near the area where the fossils were found. / In honour of the geologist Lluis Ardèvol (Geoplay, Tremp, Lleida), who discovered the Blasi sites.
Holotype: MPZ 2008/1, a partial, articulated skull comprising the skull roof and braincase.From Aren (Areny de Noguera in Catalonian language), the village of Huesca province (Spain) located near the area where the fossils were found. / In honour of the geologist Lluis Ardèvol (Geoplay, Tremp, Lleida), who discovered the Blasi sites.
Paratypes:Cranial: MPZ2008/256, fragmentary right maxilla; MPZ2008/257, fragmentary left maxilla; MPZ2008/258, left dentary with 12 teeth; MPZ2008/259, right surangular; MPZ2008/260-263, four isolated teeth. Postcranial skeleton: MPZ2007/706, MPZ2007/954- 955, MPZ2008/264-267, seven cervical vertebrae; MPZ2008/268, dorsal vertebra; MPZ2008/269-270, two dorsal ribs; MPZ2008/271, partial sacrum with ossified tendons; MPZ2004/480, pathological caudal vertebra; MPZ2006/20, 14 articulated caudal vertebrae and chevrons; MPZ2008/272, 313, two caudal vertebrae; MPZ2008/314, 330, haemal archs; MPZ2008/331- 332, two ossified tendons; MPZ2008/333a-b, right scapula (two fragments); MPZ2008/334, right coracoid; MPZ2008/336, right humerus; MPZ2008/335, fragmentary right ilium; MPZ 2007/707, right pubis; MPZ 2007/711, right femur; MPZ2008/337 left femur.
Type locality and horizon: Blasi 3 site in Aren (Huesca, Spain); lower part of the Tremp Formation; Late Cretaceous, Late Maastrichtian
Diagnosis: Lambeosaurine hadrosaurid characterized by a very prominent frontal dome, more developed than in other adult specimens; nearly vertical prequadratic process of the squamosal and jugal process of the postorbital; deltopectoral crest of the humerus oriented anteriorly. Differs from other lambeosaurines in having a unique combination of characters: short frontal, with a posterior length/with ratio estimated at 0.5; midline ridge of parietal approximately at the level of the postorbitalsquamosal bar; parietal not interposed between the squamosals in the occipital surface of the skull; lateral side of squamosal relatively low above the cotyloid cavity.