Текодонтозавр (Thecodontosaurus — «ящер с собранными зубами») — род вымерших динозавров подотряда Sauropodomorpha.

 Назван из-за зубов, сидящих в очень отличительных гнездах. Очень примитивен. Внешне схож с анхизавром, за исключением более длинной шеи и хвоста и некоторых других особенностей. Этот род известен по более ста животным — как скелетам, так и отдельным костям, принадлежащих как молодым, так и взрослым животным длиной до 2,6 м и весом 40—70 кг.

 Обитал на территории нынешней Англии (поздний триас — ранняя юра, 215—195 млн.л.н.).

 From the fragmentary remains of Thecodontosaurus most of the skeleton can be reconstructed, the main exception being the front of the skull. Thecodontosaurus had a rather short neck supporting a fairly large skull with large eyes. Its jaws contained many small- to medium-sized, serrated, leaf-shaped teeth. This dinosaur's hands and feet each had five digits, and the hands were long and rather narrow with an extended claw on each. This dinosaur's front limbs were much shorter than the legs, and its tail was much longer than the head, neck and body put together. On average, it was 1.2 metres (3.9 ft) long, 30 centimetres (12 in) tall, and weighed 11 kilograms (24 lb). The largest individuals had an estimated length of 2.5 metres (8.2 ft).

 Michael Benton in 2000 noted the existence of a robust morph in the population, seen by him as a possible second species or, more likely, an instance of sexual dimorphism. Benton also indicated some unique derived traits, or autapomorphies for the species: a long basipterygoid process on the braincase; a dentary that is short in relation to the total length of the lower jaw; an ilium that has a back end that is subquadrate instead of rounded.

 The small size has been explained as an instance of insular dwarfism.

 Riley and Stutchbury originally saw Thecondontosaurus as a member of the Squamata, the group containing lizards and snakes. This did not change when Richard Owen in 1842 coined the Dinosauria, because Owen did not recognise Thecodontosaurus as a dinosaur; in 1865 he assigned it to the Thecodontia. Only in 1870 was Thomas Huxley the first to understand it was a dinosaur, though referring it incorrectly to the Scelidosauridae. Later it would normally be placed in either the Anchisauridae or its own Thecodontosauridae.

 Modern exact cladistic analyses have not been conclusive. Although not actually the earliest member of the group, Thecodontosaurus is sometimes placed in a very basal position among the sauropodomorph dinosaurs. It was earlier included under the Prosauropoda but more recently it has been suggested that Thecodontosaurus and its relatives were prior to the prosauropod-sauropod split. New reconstructions show that its neck is proportionally shorter than in more advanced early sauropodomorphs.

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Tags: Вымершие рептилии, Триас, авеметатарзалии, архозавроморфы, архозавры, диапсиды, динозавроморфы, динозавры, завроподоморфы, ящеротазовые

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