vertebrae that supports the tail feathers. The shorter tail and the higher position of the shoulder indicated by the strut-like coracoid — allowing for a greater wing amplitude — improved manoeuvrability, turning and swooping at speed. Flying speed may have been impaired due to the lack of a bony keel on the sternum as attachment for the flight muscles; it is uncertain whether a true foramen triosseum was present, through which a tendon could elevate and supinate the wing. In 1992 Iberomesornis was assigned to the Iberomesornithidae. At that time it was considered to possibly have been very basal, outside of the clade Ornithothoraces, as is reflected by its generic name. However, since the discovery of Iberomesornis, many more bird fossils have come to light in the quarries of Liaoning province, China. Well preserved specimens of Chinese species such as Sinornis and Confuciusornis have permitted scientists to better understand the birds' early fossil history. Today, Iberomesornis is seen as positioned within Ornithothoraces, as a basal member of the Enantiornithes. References Sources Enantiornitheans Bird genera Cretaceous birds of Europe Cretaceous Spain Fossils of Spain La Huérguina Formation Fossil taxa described in 1992 Taxa named by José Bonaparte