Mendozasaurus
Argentina, Mendoza (Neuquén Group)
- Mendozasaurus neguyelap
Mendozasaurus is a genus of sauropod dinosaur from the group of Titanosauria that lived during the Late Cretaceous in South America.
So far fragmentary remains are known, including, among other things, the majority of the limbs and tail vertebrae series with and be dated to the late Turonian to late Coniacian. He wore Like some other Titanosaurier skin bony plates ( osteoderms ). The only known species is neguyelap Mendozasaurus.
Features
Mendozasaurus was a great Titanosaurier and is estimated at a length of 18 to 27 meters. As with all sauropods is a four-legged herbivore with a long neck and tail. Along with the type skeleton, two small and two large osteoderms were found: The small osteoderms conform to the shape of an ellipsoid ( are convex on top and bottom ) and reach a length of 8.1 cm and a height of 4.4 cm; unlike Saltasaurus they show no spines. The larger osteoderms reach 17.5 cm in length and 15.3 cm in height, but are only slightly convex at the bottom. This type shows similarities with the osteoderms of Ampelosaurus. As with other titanosaurs the osteoderms were probably not the defense - instead, it was possibly due to calcium reservoirs.
From related genera, it can be distinguished by a unique combination of features: For example, the rear middle cervical vertebrae high spinous processes, which are laterally widened like a fan and are significantly wider than the vertebral body. The middle caudal vertebrae are mediocre procoel (on the front concave ), the posterior condyles ( condyles ) are greatly reduced and shifted upwards.
System
Within the Titanosauria Mendozasaurus will be provided to Titanosauridae ( = Lithostrotia ). He is a close relative of Futalognkosaurus - both genera are grouped together as Lognkosauria. As a sister taxon of Longkosauria Malawisaurus was proposed. In the Traukutitan described in 2011 there could be a further, late representative of the Lognkosauria.
This cladogram was simplified by Calvo and colleagues ( 2007):
Malawisaurus
Mendozasaurus
Futalognkosaurus
History of research, discoveries and naming
All previous findings come from a holding south of Cerro Guillermo locality in the Argentine province of Mendoza. The first fossils were discovered by two oilmen. Between 1998 and 2001 paleontological expeditions took place, which dug in Mendozasaurus - locality and nearby localities and adjacent to the Mendozasaurus - type copy bargen more fossils of titanosaurs, theropods and turtles. Between 2001 and 2003, cervical vertebrae also were recovered from Mendozasaurus. The rocks of the discovery site were deposited by rivers ( fluvial ) in a flood plain. They are assigned to the Río Neuquén - subgroup, a layer link in the Neuquen Group. The Mendozasaurus fossils are now in the Instituto Argentino de Ciencias y Nivología of Glaciología Ambien valley.
The holotype material ( copy number IANIGLA PV 065/1-24: 22) consists of 22, mostly in the anatomical composite encountered caudal vertebrae and two chevron bones. Together with the holotype several non- the anatomical context bones were found, including a vertebrae, a sternum ( sternum), a shoulder blade (scapula ), parts of the arm ( an upper arm bone (humerus ), radius and ulna (radius and ulna ) and four metacarpals ), parts of a pubic bone and parts of the hind legs (thigh bone (femur), shinbone ( tibia), the fibula ( Fibla ), five metatarsal bones ( metatarsals ), two claws ). While the holotype instance derived from an adult subject with built relatively slender approximately 18 meters in length, the other bones include at least one further individual, which was about 15 % larger. Even larger fossils were found in the vicinity. Later this genus cervical vertebrae were attributed from the same locality.
Mendozasaurus was described in 2003 by Bernardo González Riga for the first time scientifically. The name refers to the province of Mendoza. The second part of the species name neguyelap, two indigenous words composed of the language Millcayac together: neguy - "first" and yelap - "The Beast ". This name is intended to indicate the fact that it is the first in the province of Mendoza discovered dinosaur named.