Betasuchus

Cast of the femur, issued in Brussels

• Limburg, The Netherlands (Maastricht Formation)

• Betasuchus bredai ( Seeley, 1883)

Betasuchus is a dubious ( doubtful ) Genre theropod dinosaur from the Upper Cretaceous of the Netherlands. So far, the upper end of the thigh bone (femur) is only known that originates from the Maastricht Formation ( Maastrichtian ) near Maastricht in the province of Limburg. It is the only previous discovery of a theropod from the Maastricht Formation. Today is the Fund in the collection of the British Museum of Natural History. The only way is Betasuchus bredai.

The systematic position is controversial. However, the recent study by Carrano and Sampson (2008) comes to the conclusion that it was representative of the Ceratosauria from Europe to the last ( most recent ).

Features

It was a relatively small theropods. The femur is built very primitive compared with other theropods of the Late Cretaceous. The head was directed obliquely forward ( anteromedial ) and slightly upward ( ventrally ). The small trochanter ( Lesser trochanter ) is extended upward. A rounded hill serves as the attachment point for the musculus iliofemoralis.

Research history and systematics

Originally, the femurs of Harry Seeley (1883 ) was described as a new species of the genus Megalosaurus, as " Megalosaurus " bredai. A new description of the discovery by Friedrich von Huene (1926 ) showed, however, that this finding can not be attributed to the genus Megalosaurus ( Megalosaurus has long been used as so-called trash taxon, were assigned to the a variety of not more closely related theropods ). Instead, wrote von Huene the Fund the Ornithomimiden, a group within the Coelurosauria to calling him tentatively and informally as Ornithomimidorum genus b ( " Ornithomimosaurier genus b"). Based on this designation presented by Huene 1932, the new genus Betasuchus on (Greek beta - the second letter of the Greek alphabet; soukhos gr - "Crocodile" ).

The systematic classification of Betasuchus is controversial: So Betasuchus was by various authors as a representative of the Coelurosauria - ( Theropoda indet. ) Than look no further unclassifiable theropod, or described as a possible Abelisauride - as a Ornithomimide or as a kindred with Dryptosaurus tyrannosaur. Carrano and Sampson (2008) classify Betasuchus as a representative of the Ceratosauria.

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