Journal of Vertebrate Paleontology, 25, 850–858.Īllain, R. (2005a) The postcranial anatomy of the megalosaur Dubreuillosaurus valesdunensis (Dinosauria Theropoda) from the Middle Jurassic of Normandy, France. Journal of Vertebrate Paleontology, 22, 548–563.Īllain, R. (2002) Discovery of a megalosaur (Dinosauria, Theropoda) in the middle Bathonian of Normandy (France) and its implications for the phylogeny of basal Tetanurae. (2001) Redescription de Streptospondylus altdorfensis, le dinosaure théropode de Cuvier, du Jurassique de Normandie. An early Middle Jurassic origin of tetanurans is preferred.Īllain, R. Older records of tetanurans have been proposed, but most of these have been refuted and detailed re-examination of other early reports is warranted to establish the date of origin of this clade. hesperis: a prominent anterior process of the maxilla the presence of band-like dental enamel wrinkles the maxillary 'fenestra' is present but takes the form of an imperforate fossa (a spinosauroid synapomorphy) and the paradental groove is wide anteriorly, defining a distinct gap between the interdental plates and the medial wall of the dentary (a synapomorphy of Spinosauridae + Megalosauridae). Several features confirm the tetanuran affinities of D. hesperis possesses two autapomorphies of the maxilla: a deep groove on dorsal surface of the jugal process containing numerous pneumatic foramina and an array of small foramina in the ventral part of the articular surface for the premaxilla.

Therefore a new genus, Duriavenator, is erected to form the new combination D.

Several features of ‘M.’ hesperis demonstrate that it is distinct from the lectotype dentary of Megalosaurus: an enlarged, subcircular third alveolus and subcylindrical, anteriorly inclined anterior dentary teeth an anterior Meckelian foramen located almost directly anterior to the posterior Meckelian foramen low interdental plates and a prominent lip bounding the Meckelian groove ventrally, anterior to the Meckelian fossa. Abstract ‘Megalosaurus’ hesperis from the Inferior Oolite (Bajocian, Middle Jurassic) of Dorset, UK is redescribed.

Oolite review