Ampelosaurus ( ; meaning "vine lizard") is a titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now France. Its type species is A. atacis, named by Le Loeuff in 1995. Its remains were found in a level dating from 71.5 million years ago representing the early Maastrichtian.
Like most sauropods, it would have had a long neck and tail but it also carried armor in the form of osteoderms. In 2005, over 500 bones have been assigned to Ampelosaurus and additional material has been found since, including a partially articulated skeleton with skull, which makes it one of the best known dinosaurs in France. However, recent studies suggest that the type locality is not a monospecific titanosaur bone bed and that part of the bones attributed to Ampelosaurus probably belong to a second titanosaurian taxon.
Ampelosaurus lived on what was the Ibero-Armorican Island, a landmass including much of present-day France and Iberian Peninsula. Histological studies show characteristics related to an island environment such as a slowed growth rate. However, with a size of about in length for the largest known individual, Ampelosaurus was not an insular dwarf unlike some other Ibero-Armorican titanosaurs like Lirainosaurus and Atsinganosaurus, or the genus Magyarosaurus from the Hateg island.
Several specimens found elsewhere in France and Spain were referred to Ampelosaurus but were later identified as belonging to other titanosaurs.
Discovery and naming
Ampelosaurus is known by abundant remains from the Bellevue site near the village of Campagne-sur-Aude in the Upper Aude Valley, in Aude department in Occitania region. It was recovered in the lower levels of the Marnes Rouges Inférieures Formation, which belong to the early Maastrichtian epoch of the Late Cretaceous Period, ~ 70 million years ago. These sediments represent an ancient floodplain with numerous river channels. Historically, the dinosaurs of the Upper Aude Valley were first reported by Paul Gervais in 1877 from two vertebrae discovered in the commune of Fa. The first discoveries of dinosaur bones at Campagne-sur-Aude date back to the beginning of the twentieth century, but they remained isolated and were quickly forgotten. It was not until 1982 that dinosaurs localities of the Upper Aude Valley were rediscovered by local amateurs, Pierre Clottes and Christian Raynaud, following the accidental discovery of a fossil bone in Campagne-sur-Aude by a hunter a year earlier. Clottes and Raynaud mainly discovered caudal vertebrae and limb bones during simple surface collecting carried out at several sites around the villages of Campagne-sur-Aude and Espéraza. In 1989, the first systematic excavations carried out by professional paleontologists began on the main site, located at the Bellevue farm. Several excavation campaigns brought to light numerous bones of an unknown sauropod. This new dinosaur was named Ampelosaurus atacis by the French paleontologist Jean Le Loeuff in a preliminary description published in 1995. Ampelosaurus is derived from the Greek αμπελος, "the vine" and the Latinised Greek saurus, "reptile". Therefore, Ampelosaurus means "vineyard lizard" after the Blanquette de Limoux vineyard. The vineyard is located on the south side of the region Ampelosaurus was found in. The specific name is based on the Latin atax, the "Aude river". Only one tooth, three articulated dorsal vertebrae (the holotype MDE-C3-247), and the neural spine of another dorsal vertebra were illustrated, whereas the material known at that time also included other dorsal and caudal vertebrae, ribs, chevrons, limb bones, shoulder and pelvis bones, from several individuals. Four osteoderms discovered at Bellevue and described in 1994 were also attributed to Ampelosaurus in 1995. In 2005, Le Loeuff published a more complete description of the bones discovered since 1989 including a braincase and a right dentary. In 2001 was found a relatively complete skeleton of a young adult about 10 m long, nicknamed "Eva" after the name of Eva Morvan the student who discovered the first elements. Several excavation campaigns were necessary (until 2006) to extract this skeleton. This specimen, which as yet to be described, includes an almost complete disarticulated skull of which only a few elements are currently on display in the Dinosaur Museum of Espéraza. In 2007, the remains of a larger specimen were discovered, including a sternal plate, a scapula, a 1.20 m femur, a pubis, a caudal vertebra and a chevron.