Eustreptospondylus

Eustreptospondylus ( ;), from (Ancient Greek εὖ (eû), meaning "well", στρεπτός (streptós), meaning "twisted", and σπόνδυλος (spóndulos), meaning "vertebra"), is an extinct genus of megalosaurid theropod dinosaur, from the Callovian and Oxfordian stages of the Jurassic period (some time between 166 and 154 million years ago) in southern England, at a time when Europe was a series of scattered islands (due to tectonic movement at the time which raised the sea-bed and flooded the lowland).

==Discovery and naming== thumb|left|Nopcsa's 1905 skeletal restoration In 1870, workers at the Summertown Brick Pit, just north of Oxford, England, found the skeleton of a theropod. The remains were acquired by the local bookseller James Parker, who brought them to the attention of Oxford Professor John Phillips. Phillips described the bones in 1871, but did not name them. At the time, the remains represented the most complete skeleton of a large theropod ever found. Eustreptospondylus is still the most complete of any large Jurassic European theropod. In 1890, the skeleton was bought by Oxford University, and Arthur Smith Woodward examined it and referred it to Megalosaurus bucklandii. In 1905 and 1906 Baron Franz Nopcsa reassigned the skeleton to the species, Streptospondylus cuvieri, which had been first described by Sir Richard Owen in 1842, based on a now lost vertebra from the Bathonian stage of the Jurassic period. The reason for this assignment was that the type species Streptospondylus altdorfensis from France, was a clearly related form, and Nopcsa decided to subsume all British material of this nature under a single Streptospondylus species, for which then the name S. cuvieri could not be avoided. The assignment of a rather complete find to a species based on very poor remains was troublesome. This was compounded by German palaeontologist Friedrich von Huene, who sometime referred to the specimen as Streptospondylus cuvieri and at other times considered it a species of Megalosaurus: Megalosaurus cuvieri.