Mamenchisauridae

Skeletal reconstruction of Mamenchisaurus youngi in Zigong Museum

  • People's Republic of China

The Mamenchisauridae are a group of sauropod dinosaurs, their spatial and temporal distribution is restricted to the Middle and Upper Jurassic of China. These four-legged herbivores showed the longest in proportion necks of all sauropods.

Features

It was medium to large sauropods. Striking was the extremely long, at least 17 ​​and in the extreme case of 19 cervical vertebrae existing neck. The skull was small in proportion to body; that of the Mamenchisaurus was slightly longer and thinner than that of the Camarasaurus and pointed spatulate teeth. The spinous processes of the vertebrae were relatively low, the ribs were greatly extended. Key characteristics of the group were also the four sacral vertebrae and the ninth and tenth dorsal vertebrae that were fused together.

System

The sauropods split into two specialized groups - the Diplodocoidea with forms such as Apatosaurus and Dicraeosaurus and Macronaria with forms like Brachiosaurus and Saltasaurus. Both groups are summarized as Neosauropoda. The Mamenchisauridae splits off from the main line, which leads to the Neosauropoda is therefore classified outside The summit, making it more original. Together with the Neosauropoda and various other genera form the original Mamenchisauridae the group of Eusauropoda.

Antetonitrus

Vulcanodon

Spinophorosaurus

Shunosaurus

Barapasaurus

Patagosaurus

Mamenchisaurus

Omeisaurus

Cetiosaurus

Jobaria

Neosauropoda

Taxonomy

The taxon Mamenchisauridae were erected in 1972 by the Chinese paleontologist Yang Zhongjian and Zhao Xijin. Initially, it contained only a single genus with Mamenchisaurus (monotypic ). Until today Mamenchisaurus attributed at least seven different species, the validity of many of these types, however, is controversial. As remarkable Paul Upchurch and colleagues ( 2004) that Mamenchisaurus was a " trash can taxon " - a genre that is attributed to a variety of fossil material without these assignments were adequately substantiated by anatomical features. Thus, a revision of the genus was necessary.

To date, the Mamenchisauridae were attributed to various other genera, but these associations are partly controversial. The other, often conducted within the Mamenchisauridae genera include Chuanjiesaurus, Eomamenchisaurus, Tienshanosaurus, Tonganosaurus, Omeisaurus and Yuanmousaurus.

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