Altispinax
A theropod with tall spines from Early Cretaceous England.
Altispinax is a genus of large predatory theropod dinosaur from the Early Cretaceous period, living between 140 and 133 million years ago. Its fossils were found in the Wadhurst Clay Formation of East Sussex, England. The genus is notable for the very tall spines on its back vertebrae, which give it its name meaning 'with high spines.'
Quick Facts
- Species
- dunkeri
Facts from the source article.
History
Fossil collector Samuel Husbands Beckles discovered nodules containing dinosaur bones in a quarry near Battle, East Sussex, probably during the early 1850s. He sent them to palaeontologist Richard Owen, who reported them in 1856. Owen had a lithograph made by Joseph Dinkel of the main specimen, three back vertebrae with very tall spines. An 1884 edition of an 1855 volume of Owen's work on British fossil reptiles included this image, leading to a mistaken belief that the fossils were found near 1884. Owen referred the specimens to Megalosaurus bucklandii and thought the vertebrae were from the shoulder region. In 1888, Richard Lydekker compared these vertebrae with material referred to Megalosaurus dunkeri. Friedrich von Huene created the genus Altispinax in 1923, using the three vertebrae as the basis. The combination Altispinax dunkeri was first used in 1939 by Oskar Kuhn.
Description
Paul in 1988 tentatively estimated that Altispinax weighed 1 tonne and was shorter than the type specimen of Acrocanthosaurus atokensis, which measures about 8 meters long. According to Ralph Molnar, the two spines closest to the skull are ankylosed, with the single closest spine about two-thirds the height of the others and appearing broken off, while the spine behind partly overgrows the gap. Molnar explained this as a result of injury to a back frill. In 2003, Darren Naish gave a different interpretation, suggesting the gap was natural and denying that the front two vertebrae were ankylosed, but noting that the spines of the eleventh and twelfth vertebrae were joined at the top. Naish also pointed out that Owen had noted large depressions on the neural arch sides and explained them as pneumatisation, possibly the first such observation in a dinosaur. Olshevsky assigned Altispinax to Eustreptospondylidae; Naish in 2003 considered it a member of Allosauroidea, but most researchers place it as Tetanurae incertae sedis.
More in Dinosaurs of the United Kingdom
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced