Elrhazosaurus

Elrhazosaurus (meaning "Elrhaz lizard") is a genus of basal iguanodontian dinosaur, known from isolated bones found in Early Cretaceous rocks of Niger. These bones were initially thought to belong to a species of the related dryosaurid "Valdosaurus", but have since been reclassified.
Discovery and history.
"Elrhazosaurus" is based on MNHN GDF 332, a left thigh bone collected by Philippe Taquet from the upper part of the Elrhaz Formation of Gadoufaoua in the Ténéré Desert, Agadez, Niger. This rock unit dates to the late Aptian stage, approximately 115 million years ago. The bone was designated as the type specimen of a new species of "Valdosaurus" ("V. nigeriensis") by Peter Galton and Taquet in 1982. It was differentiated from the type species "V. canaliculatus" by the locations of trochanters and other details. Because "V. canaliculatus" is known from Europe, the presence of a related species in central Africa was interpreted as evidence for a land connection between the two continents.
"V. nigeriensis" was given its own genus, "Elrhazosaurus", by Galton in 2009. This was done on the grounds of differing morphology and geologic age versus "V. canaliculatus". He retained it as a dryosaurid. While "Elrhazosaurus" is sometimes described as only known from thigh bones, at least one upper arm bone has been assigned to the genus.
Paleoecology and paleobiology.
The Elrhaz Formation is mostly made up of fluvial sandstones. A diverse assemblage of fossil animals has been recovered, including freshwater bivalves, hybodont sharks, bony fish, turtles, several genera of crocodylomorphs ("Anatosuchus", "Araripesuchus", "Sarcosuchus", and "Stolokrosuchus"), undescribed ornithocheirid pterosaurs, the theropod dinosaurs "Eocarcharia", "Kryptops", "Suchomimus", and an undescribed noasaurid (possibly "Bahariasaurus"), the sauropods "Nigersaurus" and an undescribed titanosaurian (possibly "Malawisaurus"), and the iguanodontians "Lurdusaurus" and "Ouranosaurus". As a dryosaurid iguanodontian, "Elrhazosaurus" would have been a lightly built herbivorous bipedal runner.