A new specimen of Valdosaurus canaliculatus (Ornithopoda: Dryosauridae) from the Lower Cretaceous of the Isle of Wight, England

Abstract

The anatomy of Valdosaurus canaliculatus is incompletely known and until recently was based exclusively upon the holotype femora. Additional discoveries from the Wessex Formation (Barremian) of the Isle of Wight during the past decade have considerably expanded the amount of material available and offered insights into the morphology of the vertebral column and pelvis. However, all of these specimens consist primarily of hind limb material. Here, I describe a newly discovered individual of this taxon, the most complete yet found, which was found in articulation and includes a partial dorsal series, an almost complete tail, pelvic material, and both hind limbs. Although the specimen is partially crushed it offers new information on the anatomy of Valdosaurus, facilitating comparisons with other dryosaurid taxa.

Paleontological discoveries in the Chorrillo Formation (upper Campanian-lower Maastrichtian, Upper Cretaceous), Santa Cruz Province, Patagonia, Argentina

“…This process is oval in cross-section. The articular margin is almost flat and slightly projected ventrally in a short process, being not fused with the obturator process, indicating a posteriorly opened obturator foramen, resembling the condition of basal ornithopods (e.g., Hypsilophodon, Gasparinisaura, Anabisetia, Trinisaura; Galton, 1974a;Coria & Calvo, 2002;Cambiaso, 2007;Barrett et al, 2011;Coria et al, 2013). Femur (Figures 7, 11).…”

“…Distal caudals are indistinguishable from other basal ornithopods (e.g. Gasparinisaura, Anabisetia, Talenkauen, Macrogryphosaurus, Diluvicursor, Sektensaurus, Trinisaura, Jeholosaurus;Coria & Salgado, 1996;Cambiaso, 2007;Calvo et al, 2007;Barrett et al, 2011;Han et al, 2012;Barrett, 2016;Herne et al, 2018;Ibiricu et al, 2019;Rozadilla et al, 2019). Scapula ( Figure 10).…”

“…The lateral condyle is subtriangular in proximal view. It shows a well-developed process at the anterolateral corner, being absent in other basal ornithopods such as Gasparinisaura, Anabisetia, Talenkauen, Jeholosaurus, Kangnasaurus, Notohypsilophodon, Hypsilophodon, Zalmoxes, Trinisaura, and the iguanodontian Ouranosaurus (Galton, 1974a;Cooper, 1985;Coria & Salgado, 1996;Cambiaso, 2007;Godefroit et al, 2009;Barrett et al, 2011;Han et al, 2012;Ibiricu et al, 2014;Bertozzo et al, 2017;Rozadilla et al, 2019). The lateral surface of the lateral condyle is convex and rugose.…”

Anatomy, taphonomy, and phylogenetic implications of a new specimen of Eolambia caroljonesa (Dinosauria: Ornithopoda) from the Cedar Mountain Formation, Utah, USA

“…The proximal end is craniocaudally expanded; however, the iliac and pubic peduncles are missing and only the base of the obturator process is present. The shaft is straight, as in the dryosaurid Valdosaurus [42], Uteodon [26,73], Mantellisaurus (IRSNB 1551, NHMUK R3741) [62], Altirhinus [67], Bolong [63], Bactrosaurus [72], Gilmoreosaurus [74], and Yunganglong [15]. The distal end of the ischium is a cranially-expanded boot (Fig 9H).…”

“…The matrix also was used and modified by Barrett et al [42], Escaso et al [43], Zheng et al [44], Shibata and Azuma [45], Gasca et al [46], and Verdú et al [47]. …”