Tall spined vertebra

Acrocanthosaurus is classified in the superfamily Allosauroidea within the infraorder Tetanurae. This superfamily is characterized by paired ridges on the nasal and lacrimal bones on top of the snout and tall neural spines on the neck vertebrae, among other features.[3] It was originally placed in the family Allosauridae with Allosaurus,[4] an arrangement also supported by studies as late as 2000.[2] Most studies have found it to be a member of the related family Carcharodontosauridae.[3][8][9]

At the time of its discovery, Acrocanthosaurus and most other large theropods were known from only fragmentary remains, leading to highly variable classifications for this genus. J. Willis Stovall and Wann Langston, Jr. first assigned it to the "Antrodemidae," the equivalent of Allosauridae, but it was transferred to the taxonomic wastebasket Megalosauridae by Alfred Sherwood Romer in 1956.[10] To other authors, the long spines on its vertebrae suggested a relationship with Spinosaurus.[11][12] This interpretation of Acrocanthosaurus as a spinosaurid persisted into the 1980s,[13] and was repeated in the semi-technical dinosaur books of the time.[14][15]

Tall spined vertebrae from the Early Cretaceous of England were once considered to be very similar to those of Acrocanthosaurus,[16] and in 1988 Gregory S. Paul named them as a second species of the genus, A. altispinax.[17] These bones were originally assigned to Altispinax, an English theropod otherwise known only from teeth, and this assignment led to at least one author proposing that Altispinax itself was a synonym of Acrocanthosaurus.[16] These vertebrae were later assigned to the new genus Becklespinax, separate from both Acrocanthosaurus and Altispinax.[18]



Malaysia SEO company
film transference