Thecospondylus (THEEK-o-SPON-di-lus, "sheath vertebra") is a dubious genus of dinosaur from the Early Cretaceous of England Dr. A.C. Horner, an amateur geologist living at Tonbridge, in the nineteenth century acquired a fossil found in the quarry of Southborough. He sent it to paleontologist Harry Govier Seeley who in 1882 described and named it as the type species Thecospondylus Horneri. The genus name is derived from Greek theke meaning 'sheath' and spondylos meaning 'vertebra', a reference to the "extremely thin" bone forming the vertebrae. The specific name honours Horner.