In the corner of the lacrimal a shallow depression is present, which is pierced by a smaller foramen. (2008) established several traits that distinguish Eustreptospondylus from its direct relatives. Though not keeled, the front dorsal vertebrae have paired hypapophyses at their undersides, just as with Streptospondylus altdorfensis. No teeth have been preserved in either the upper or lower jaws, but the size of its toothsockets proves that the third tooth of the lower jaw was enlarged. These jaws at the front are rather tall and wide. Oblique grooves in the jaw joints caused the gape of the mouth to be widened when the lower jaws were opened. The skull of Eustreptospondylus has a rather pointed snout in side view, with a large horizontally oriented nostril. Various estimates suggest that Eustreptospondylus was an 'average-sized' theropod, with a hypothetical adult length of around 6 metres (20 ft), and a mass of 0.5 tonnes (0.49 long tons 0.55 short tons). The main specimen of Eustreptospondylus was not fully grown, and according to an estimate by Paul in 1988 was about 4.63 metres (15.2 ft) long and weighed about 218 kilograms (481 lb). The specific name 'oxoniensis', refers to its provenance from Oxford. Streptospondylus means 'turned vertebra', and is derived from the Greek words streptos (στρεπτος) meaning 'reversed' and spondylus (σπονδυλος), a reference to the fact that its dorsal vertebrae were opisthocoelous, in contrast to the typical procoelous vertebrae of crocodiles. The genus name Eustreptospondylus, was intended to mean 'true Streptospondylus'. In 1964, Alick Donald Walker clarified matters by erecting a separate genus and species for the Oxford specimen: Eustreptospondylus oxoniensis. 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. The assignment of a rather complete find to a species based on very poor remains was troublesome. 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. In 19 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. In 1890, the skeleton was bought by Oxford University, and Arthur Smith Woodward examined it and referred it to Megalosaurus bucklandi. Eustreptospondylus is still the most complete of any large Jurassic European theropod. At the time, the remains represented the most complete skeleton of a large theropod ever found. Phillips described the bones in 1871, but did not name them.

The remains were acquired by the local bookseller James Parker, who brought them to the attention of Oxford Professor John Phillips. In 1870, workers at the Summertown Brick Pit, just north of Oxford, England, found the skeleton of a theropod.

Prehistoric kingdom yutyrannus