Atsinganosaurus

• France, Bouches -du -Rhône

• Atsinganosaurus velauciensis

Atsinganosaurus is a genus of sauropod dinosaur from the group of Titanosauria whose remains were discovered in the Upper Cretaceous of southern France.

This genus was first described in 2010 with the single species, Atsinganosaurus velauciensis by French paleontologists to Géraldine Garcia. Atsinganosaurus is known by various elements of the residual skeleton ( Postkranium ) as well as teeth that have been discovered in the locality La Bastide Neuve near the town velaux. These remains belong to at least two adult individuals. This genus is, after Lirainosaurus, Ampelosaurus and Magyarosaurus, the fourth discovered Titanosauria from the Upper Cretaceous of Europe.

Features

Atsinganosaurus was a slender Titanosauria. Of the other known European titanosaurs can distinguish this genus by a combination of diagnostic features. For example, the cylindrical roots and the crowns are slightly spatulate. The vertebrae are missing Hyposphen - Hypantrum connections, as with most other Titanosauria except some basal forms such as Andesaurus. The sacrum ( sacrum ) consists of five ophistocoelen (on the rear side of the concave ) vertebrae; other hand, many abgeleitetere Titanosauria had six sacral vertebrae. Only the anterior caudal vertebrae were strongly procoel (on the front concave), as Malawisaurus. The foramen ( opening) of the Rabeinbeins ( coracoid ) was centrally located to the top and bottom of the Raven leg. The lower end of the upper arm bone ( humerus) is slightly expanded at an angle.

System

Atsinganosaurus shows a combination of modern and original ( plesiomorphic ) characteristics of a Titanosauria. Especially many features in common shares this genus with basal Lithostrotia, and in particular with Malawisaurus. The Lithostrotia are a group within the Titanosauria that includes the most original except some genera with. Although the describer no published phylogenetic analysis, they expect by this combination of features that Atsinganosaurus was an original representative of Lithostrotia.

Palaeobiogeography

During the Late Cretaceous, Europe was an archipelago. Atsinganosaurus lived with at least two other Titanosaurier genera on the Iberian- Armorischen island, which was about three times as large as the present-day Madagascar. Presumably, this island was temporarily connected by land bridges to other landmasses as the Transylvanian islands in eastern Europe. Since Atsinganosaurus shares a number of common features with the African Malawisaurus, the researchers suggest a temporary hiking route between Europe and Africa.

Fund and naming

The site La Bastide Neuve is located near the city velaux in the French Department Bouches -du -Rhône and was discovered in 1992 by Xavier Valentin. The bones are well preserved and have been discovered in an area of ​​six square meters. The bones were found along with the remains of other vertebrates such as turtles and the teeth of crocodiles, theropods, and Nodosauriden Rhabdodontiden. The Sauropodenknochen belong to at least two individuals. As the degree of fusion of the vertebral arches and the cervical and sacral ribs indicating the vortex centers include the bone to adult individuals. Some skeletal parts were found in the anatomical network.

In the rocks of the discovery site is glaukonitische limestones, which are classified according to the Dunham classification as grainstone. These sediments were probably deposited during the Upper Campanian what fossils of certain Charophyta and dinosaur eggshells indicate characteristic as time markers for a certain time interval ( biostratigraphy ). Probably the sediments were deposited along a coast, to which fossils of mainly marine decapods ( Decapoda ) point, which were discovered in connection with the bone.

The holotype material ( copy number VBN.03.01.a, b, c, d) consists of four linked rear ( posterior ) vertebrae. Other discoveries include teeth, three cervical vertebrae, a further vertebrae, a sacrum, a total of four caudal vertebrae, a shoulder blade (scapula ) and a scapula with coracoid ( Scapulocoracoid ), two humeri, one metacarpal and a metatarsal one with. The bones are in the collections of various French institutions: the University of Poitiers, the Musée de Paleontology of the University of Provence Aix -Marseille I, the Musée de Archaeological velaux and the Musée d' Histoire Naturelle d' Aix -en- Provence.

The name Atsinganosaurus means so much like gypsies lizard and is derived from the Greek Athinganos ( Gypsies) from what is intended to indicate the presumed migration between Eastern and Western Europe. The Artepitheth velauciensis has the city velaux where the fossils were discovered.