Hypselospinus is a genus of iguanodontian dinosaur which was first described as a species of Iguanodon (I. fittoni) by Richard Lydekker in 1889, the specific name honouring William Henry Fitton. In May 2010 the fossils comprising Hypselospinus were by David Norman reclassified as a separate genus, among them the holotype BMNH R1635, consisting of a left ilium, a sacrum, tail vertebrae and teeth. The generic name is derived from Greek hypselos, "high" and Latin spina, "thorn", in reference to the high vertebral spines. Later that same year, a second group of scientists independently re-classified I. fittoni into a new genus they named Wadhurstia, which thus is a junior objective synonym of Hypselospinus. Hypselospinus lived during the lower Valanginian stage, around 140 million years ago. A