A second species, Anoplosaurus major, "the larger one", was named by Seeley in 1879 for a neck vertebra and three partial caudal vertebrae he removed from the material previously referred to Acanthopholis stereocercus, from the same formation as the type species.
In 1879, Seeley described a second species of dinosaur, Anoplosaurus major ("the larger one"), based on neck vertebrae and caudal vertebrae he found in the same geological formation as the original Acanthopholis stereocercus.