Stegopelta

History

In 1905, Samuel Wendell Williston described FMNH UR88, a partial armored dinosaur skeleton consisting of a maxilla fragment, seven cervical and two dorsal vertebrae, part of a sacrum and both ilia, caudal vertebrae, parts of the scapulae, both humeral heads, portions of an ulna and both radii, a metacarpal, partial tibia, metatarsal, and armor including a shoulder spine and neck ring. The specimen was in poor condition, as it had eroded from a slope and been walked on by cattle. Ankylosaurians being very poorly known, Williston compared his new genus to Stegosaurus, and the armor to that of Glyptodon; like that mammal, Stegopelta had a fused section of armor (in its case over the pelvis). Roy Lee Moodie redescribed it in 1910, and considered it to be close to, if not the same as, Ankylosaurus.

The genus fell into obscurity. Walter Coombs synonymized it with the more famous but equally poorly known Nodosaurus in his 1978 redescription of the Ankylosauria. It was reinstated as a valid genus by Ken Carpenter and James Kirkland (1998), who recognized it as having distinct vertebral and armor characteristics. Tracy Ford took this farther in 2000, assigning it to a new subfamily in Ankylosauridae based on armor characteristics, which he called Stegopeltinae. Also included was Glyptodontopelta. This has not been generally accepted, but most recent reviews have accepted Stegopelta as a distinct genus with uncertain affinities.