Valdosaurus

Phylogeny: Dinosauria > Ornithischia > Genasauria > Neornithischia > Cerapoda > Ornithopoda > Iguanodontia > Dryosauridae

Overview: Valdosaurus was a medium-sized, bipedal herbivore that lived in what is now England some one hundred and thirty million years ago. Fossils attributed to the genus are known from the Wessex Formation and other formations of similar age. Valdosaurus probably lived alongside a wide array of other dinosaurs including the sauropod Ornithopsis, the armored Polacanthus, various ornithopods like Iguanodon or Mantellisaurus, and predatory dinosaurs like Neovenator (a major threat to Valdosaurus itself). These dinosaurs shared a seasonal environment with landscapes of rivers and lake-dotted forests. Potential sources of food for Valdosaurus included cycads, ferns, conifers and other such plants. Lacking armor and being of a moderate size, this dinosaur had little means of defense beyond evasion, camouflage or living in groups.

The generic name of Valdosaurus, coined in 1977, refers to the Wealden Group – a series of geological formations in the south of England, which includes the Wessex Formation. The first known fossils of Valdosaurus, consisting of leg bones, were found in the 1880’s, on the Isle of Wight, located off England’s southern coast. They weren’t recognized as a distinct genus at that time, being referred to Hypsilophodon and soon after to the genus Camptosaurus as a supposed new species. Both dinosaurs, like Valdosaurus, belonged to the clade Ornithopoda, but this animal wasn’t especially closely related to either of them. By the 1970’s, it was recognized to have been closer to North America’s Dryosaurus and was even referred to said genus for a time, before being recognized as a distinct taxon. Valdosaurus and Dryosaurus are both classified in the family Dryosauridae.