What is "hironosaurus"

"Hironosaurus" (meaning "Hirono lizard") is the informal name given to an as-yet undescribed genus of dinosaur from the Late Cretaceous. Found in Hirono, Fukushima, Japan, it was probably a type of hadrosaur, although no subfamily identification has been made. The fossils are quite fragmentary, and consist of teeth and a vertebra, possibly from the tail. Since the fossils have never been fully described in a scientific paper, "Hironosaurus" is considered a nomen nudum. It was first mentioned by Hisa in an obscure 1988 publication and was later (1990) brought to a wider audience by David Lambert. Dong Zhiming, Y. Hasegawa, and Y. Azuma regarded the material as belonging to a hadrosaurid, but lacking any characteristics to allow more precise identification (thus indeterminate).