was a modern diagnosis of G. mongoliensis, as the 1975 one was found to be lacking. They also specifically touched on the idea the two Iren Dabasu hadrosaurs could be synonyms as Rozhdestvensky had thought. This idea was rejected, with numerous differences between the two found. Studies since the redescription have been able to include Gilmoreosaurus in research on hadrosaur phylogeny. Description Gilmoreosaurus was a relatively large-sized hadrosauroid which could grow up to long and obtain weights between . The genus can be distinguished from other hadrosauroid taxa in having a very reduced paddle-shaped postacetabular process and an asymmetrical manual phalanx III-1 end. Although the preserved elements are very sparse and probably representing more than one individual, the specimen AMNH FARB 30729 represents a single animal composed by a left ulna and radius. Skull and dentition A complete skull articulated is not known from the multiple specimens, however, numerous elements are known such as the right maxilla, dentary, jugal, squamosal and two lacrimals, quadrate and a complete predentary. In a lateral view, the right maxilla of specimen AMNH FARB 30653 is triangular in shape with various foramina on the surface. On the inner side 26 alveolar foramen are preserved and 22 alveoli are filled with teeth but the total count may be unknown due to incompleteness, the surface of this side is rather flat. The teeth are oval-shaped with a moderately pinched upper end and have coarse denticles, these denticles have three diminutive pointed structures. It appears to be that the dentary teeth were more flattened with a pinched lower end as indicated by nine isolated teeth. In all teeth, a ridge-like structure is located at the center. An isolated and partial right jugal is represented by AMNH FARB 30657, which has lost most of the anterior area in the rostral joint. It has a triangular-shaped form in a lateral view and flattened to the inner sides. The partial rostral joint is square and the lateral surface is somewhat concave but in the medial surface the articulation for the maxilla can be identified. The upper surface of the rostral joint forms a flattened socket-like structure that continues towards the rear with the base of the postorbital ramus. This ramus is projected to the top and slightly tilted towards the rear. The upper portion of the postorbital ramus is triangular when seen from the cross-section. Towards the lower end, the anterior