Malawisaurus

Live reconstruction of the head of Malawisaurus dixeyi.

• Africa (Malawi )

• Malawisaurus dixeyi ( Haughton, 1928)

Malawisaurus is a genus of sauropod dinosaur from the group of Titanosauria that lived during the Cretaceous period in Africa. Fossil remains are from the northern Malawi and close beside the bones of Postcraniums (residual skeleton) and parts of the skull with a, which is a rarity for sauropods. Malawisaurus was characterized by a short and high skull; the body was covered with skin bony plates ( osteoderms ). It was a very basal ( original ) Titanosauria. The only known species is Malawisaurus dixeyi.

Features

Malawisaurus was about 16 meters long, four-legged herbivore with a long neck and tail. The skull bones indicate a short and high skull of Brachiosaurus and Camarasaurus those more similar than the low and long heads, derived ( advanced ) Titanosauria. Thus, the snout was high, short and blunt, and then the relatively high inter-maxillary bone ( premaxilla ) points. The teeth extended over two thirds of the length of the mandible, in contrast to abgeleiteteren Titanosauria in which the teeth were limited to the foremost part of the snout. On each side of the paired mandibular ever sat 15 teeth, which were compared with abgeleiteteren Titanosauria relatively wide, but not spoon-shaped as in Camarasaurus and Brachiosaurus though.

The rest of the skeleton was characterized as in many other Titanosauria by strong procoele (on the front concave ) anterior caudal vertebrae and six sacral vertebrae from. Two types were found by osteoderms: In addition to small, scale-like elements, a larger, 19 cm long and 9.5 cm wide plate was discovered. The osteoderms are similar to those of Saltasaurus. Of all the other genera to Malawisaurus can delimit by a autapomorphy on Zwischenkieferbein: The ascending projection of this bone is oriented vertically and is located very close to the tip of the snout.

System

Malawisaurus is seen in almost all studies as one of the most original Titanosauria - only Andesaurus seems to be taking an even more original position. Notwithstanding this consensus, however, suggest two studies that Malawisaurus was more closely related to Saltasaurus and Neuquensaurus as it is Opisthocoelicaudia.

History of research and findings

The Fund was first described in 1928 by Sidney Henry Haughton as a new species of the genus Gigantosaurus - dixeyi than Giganotosaurus. The genus Gigantosaurus has already been described in 1908 by Eberhard Fraas, on the basis of fossils from the famous locality Tendaguru in Tanzania. Fraas described two species of this genus - the type species Gigantosaurus africanus and robustus Gigantosaurus. As but later turned out, the Name Gigantosaurus was already assigned to another sauropod from England, after which the genus was subsequently renamed Tornieria ( Sternfeld, 1911) - the three species have since been consequently performed as Tornieria robusta, Tornieria africana and Tornieria dixeyi. The type Tornieria robusta is now run as a separate genus under the name Janenschia, where Tornieria africana is the only valid today Tornieria type.

The Malawian kind Tornieria dixeyi was rewritten in 1993 as a separate genus of researchers led by Louis L. Jacobs - dixeyi as Malawisaurus. The name refers to the country of Malawi, where the fossils were discovered. The Fund, as has already been described by Haughton, consists of an anterior caudal vertebrae, a right pubic bone ( pubis ), a fragmentary shoulder blade (scapula ) and wishbones ( sternum). As holotype for Malawisaurus the front caudal vertebrae was selected ( copy number SAM 7405 ). In addition, Jacobs and colleagues wrote of the new species to an intermediate jaw bone ( premaxilla ), a lower jaw ( dentary ) teeth, some vertebrae, sternum and an ischium ( ischium ). The finds date from the Mwakasyunguti area in northern Malawi; the rock layers - the so-called Dinosaur Beds - belong to Lupata group.

More Malawisaurus fossils were 1987, 1989, 1990 and 1992 recovered by excursions of the Malawi Dinosaur Project, a joint project of the Malawian Ministry of Antiquities and the Southern Methodist University in Dallas (USA). The findings come from different localities in Mwakasyunguti - art and include, among others, various skull bones, vertebrae and limb elements with a. These findings, as well as another contemporary genre with a long skull, Karongasaurus were described by Elizabeth Gomani 2005.