Hongshanornis longicresta was an ornithurine bird from the late cretaceous found in the lacustrine deposits of the Lower Cretaceous Jehol Group in Inner Mongolia, China. The teeth are almost completely absent in both the upper and lower jaws, replaced with a beak, probably representing the earliest known beaked ornithurine. It is so primitive however that it cannot be ruled out that it is a more primitive pygostylian lineage. On the other hand, the validity of that supposed clade uniting Enantiornithes, Ornithurae, and more basal birds such as Confuciusornis is increasingly looking suspect, with half of the few supposed pygostylian autapomorphies - including the pygostyle itself - now known or strongly suspected to be homoplasies.
The describers of this taxon say that "the preservation of a predentary bone confirms that this structure is not unique to ornithischian dinosaurs, but was common in early ornithurine birds. The specimen recovered in 2005 is an adult with full plumage, and likely was a strong flier. Hongshanornis appears to have been a wader, feeding in shallow water or marshes. The holotype is currently held by the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing.