Ouranosaurus

Ouranosaurus is a genus of herbivorous basal hadrosauriform dinosaur that lived during the Aptian stage of the Early Cretaceous of modern-day Niger and Cameroon. Ouranosaurus measured about long and weighed . Two rather complete fossils were found in the Elrhaz Formation, Gadoufaoua deposits, Agadez, Niger, in 1965 and 1970, with a third indeterminate specimen known from the Koum Formation of Cameroon. The animal was named in 1976 by French paleontologist Philippe Taquet, the type species being Ouranosaurus nigeriensis. The generic name is a combination of ourane, a word with multiple meanings, and sauros, the Greek word for lizard. The specific epithet nigeriensis alludes to Niger, its country of discovery (in Latin, the adjectival suffix -iensis means "originating from"). As such, Ouranosaurus nigeriensis could be interpreted as "brave lizard originating from Niger".

==Discovery and naming== thumb|left|Location of the Gadoufaoua within Niger Five French palaeontological expeditions were undertaken in the Gadoufaoua region of the Sahara Desert in Niger between 1965 and 1972 and led by French palaeontologist Philippe Taquet. These deposits come from GAD 5, a layer in the upper Elrhaz Formation of the Tégama Group, which was deposited during the Aptian stage of the Early Cretaceous. On the first expedition, lasting from January–February 1965, eight iguanodontian specimens were discovered at the "niveau des Innocents" site, east of the Emechedoui wells. An additional two skeletons were discovered southeast of Elrhaz in the "Camp des deux Arbres" locality, which were given the field numbers GDF 300 and GDI 381. Both were collected in the February–April 1966 expedition, the former including a nearly complete but scattered skeleton and the latter a skeleton that was two-thirds preserved. The skeletons then in 1967 were brought to the Muséum National d'Histoire Naturelle of Paris, where they were prepared. GDF 381 was recategorized with the number MNHN GDF 1700 and then later described in 1999 as the holotype of the new taxon Lurdusaurus arenatus. While the third expedition did not turn up additional iguanodontian material, the fourth in January–March 1970 uncovered a nearly complete and partially articulated skeleton lacking the skull, south of the "niveau des Innocents" site, and was also given the field number GDF 381. This specimen was collected and taken to the MNHN by the fifth expedition in 1972. Following a subsequent Italian-French expedition led by Taquet and Italian palaeontologist Giancarlo Ligabue that turned up a potential additional iguanodontian specimen, Ligabue offered to donate the nearly complete specimen and a skull of Sarcosuchus to the Municipality of Venice, which accepted the offer and subsequently mounted the skeleton in 1975 at the Museo di Storia Naturale di Venezia.