Dornraptor Temporal range: Late Sinemurian, [1] | |
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Known fossil material | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Clade: | Averostra |
Genus: | † Dornraptor |
Species: | †D. normani |
Binomial name | |
†Dornraptor normani | |
Synonyms | |
Dornraptor (meaning "Dorset robber or thief") is an extinct genus of averostran theropod dinosaur from the Early Jurassic (Late Sinemurian) of Charmouth, Dorset, England. The genus contains a single species, D. normani, known from a fragmentary knee joint and femur that were initially described by Sir Richard Owen as belonging to the early armored dinosaur Scelidosaurus . [5] Dornraptor lived in what is now England, along other theropods like Dracoraptor and Sarcosaurus .
Dornraptor was described as having come from the Blue Lias Formation in 2024, although previous authors proposed a corrected locality of the Charmouth Mudstone Formation. [1]
In 1858, Richard Owen received fragmentary dinosaur leg bones discovered by James Harrison in Charmouth, Dorset. These included a right knee joint—comprising the articulated distal end of the femur and a proximal third of the tibia and fibula—and a partial left femur. He used them as part of the type material of the thyreophoran Scelidosaurus when describing it in 1859. [5] [6] Subsequent studies reconsidered their classification, suggesting early theropod affinities within the Saurischia, rather than an early thyreophoran within the Ornithischia. [2]
The informal name "Merosaurus newmani" was coined by Samuel Paul Welles, H. P. Powell, and Stephan Pickering in 1995 in an unpublished manuscript for the theropod material. [3] [4] [7] Carrano and Sampson (2004) proposed that the articulated knee joint likely belonged to a basal, indeterminate tetanuran theropod. [8] Darren Naish and David Martill (2007) also assigned these specimens to the Tetanurae. [9] In 2010, Roger Benson suggested that the bones could be attributed to the Coelophysoidea, while ultimately concluding that both specimens were indeterminate theropods. [10]
In 2024, Dornraptor normani was formally described as a new genus and species of averostran theropod by Matthew G. Baron. He established BMNH 39496, the right knee joint, as the holotype specimen. The partial fibula originally described by Owen as belonging to this specimen has since been lost. GSM 109560, the left femur, was also referred to the genus. The generic name, Dornraptor, combines "Dorn", an abbreviated form of the Anglo-Saxon Dornwaraceaster —referring to the English region of Dorset—with the Latin word "raptor", meaning "robber" or "thief", which is frequently used in the names of small- and medium-sized theropods. The specific name, normani, honours British palaeontologist David B. Norman. [2]
Dornraptor stands out from other theropods due to a large scar along the medial side of the distal end of the femur, a medial distal crest, and a prominent anterior trochanter separated from the head by a cleft. Additionally, it possesses a shallow trochanteric shelf and a foramen on the anterior surface of the femur. Its femur also features a deep anterior sulcus between the articular condyles and a medial condyle with similar anteroposterior diameter to the width of the articular surface. Dornraptor exhibits an elongated cnemial crest reaching proximally beyond the medial and lateral condyles, along with a pronounced fibular crest extending up to the proximal end of the tibia. The lateral side of the tibia also displays a sharp crest parallel to the fibular crest, forming a distinct bulge distally. Additionally, the proximal end of the tibia shows a separate crest, not connected to the fibular crest, and a noticeable cleft between the posterior condyles. Lastly, the lateral condyle of the tibia forms an acute angle when viewed from the medial side. [2]
Early reviews of the fossil material suggested coelophysoid, tetanuran, and ceratosaurian affinities. [10] [8] [9]
While specimens BMNH 39496 and GSM 109560 lack anatomical overlap, their discovery in the same stratigraphic unit, along with similar size and proportions, suggests they belong to the same taxon, distinct from earlier forms and contemporaneous taxa like Dracoraptor and Sarcosaurus . Utilizing a modified version of the Baron et al. (2017) phylogenetic dataset, [11] Dornraptor was found to be an early-branching averostran theropod in a polytomy with Elaphrosaurus , Cryolophosaurus , and the clade containing Allosaurus and Piatnitzkysaurus . This clade was recovered as the sister group to a clade containing the ceratosaurs Eoabelisaurus and Ceratosaurus . These results are displayed in the cladogram below, with Dornraptor and the contemporary non-averostrans Dracoraptor and Sarcosaurus in bold: [2]
Scoring Dornraptor in other matrices also resulted in its placement in various basal positions within the Averostra, outside of the major clades Abelisauroidea and Coelurosauria. [2]
Lesothosaurus is a monospecific genus of ornithischian dinosaur that lived during the Early Jurassic in what is now South Africa and Lesotho. It was named by paleontologist Peter Galton in 1978, the name meaning "lizard from Lesotho". The genus has only one valid species, Lesothosaurus diagnosticus. Lesothosaurus is one of the most completely-known early ornithischians, based on numerous skull and postcranial fossils from the Upper Elliot Formation. It had a simpler tooth and jaw anatomy than later ornithischians, and may have been omnivorous in some parts of the year.
Cryolophosaurus is a genus of large theropod dinosaur known from only a single species Cryolophosaurus ellioti, from the early Jurassic of Antarctica. It was one of the largest theropods of the Early Jurassic, with the subadult being estimated to have reached 6–7 metres (20–23 ft) long and weighed 350–465 kilograms (772–1,025 lb).
Coelophysoidea is an extinct clade of theropod dinosaurs common during the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a superficial similarity to the coelurosaurs, with which they were formerly classified, and some species had delicate cranial crests. Sizes range from about 1 to 6 m in length. It is unknown what kind of external covering coelophysoids had, and various artists have portrayed them as either scaly or feathered. Some species may have lived in packs, as inferred from sites where numerous individuals have been found together.
Gasosaurus is a genus of tetanuran theropod that lived approximately 171.6 to 161.2 million years ago during the middle of the Jurassic Period. The name "Gasosaurus" is derived from the English "gasoline" and the Greek σαῦρος. Only one species is currently recognised, G. constructus, from which the specific name honours the gasoline company that found the Dashanpu fossil quarry in Sichuan Province, China, now named as the Lower Shaximiao Formation.
Scelidosaurus is a genus of herbivorous armoured ornithischian dinosaur from the Jurassic of England.
Allosauridae is an extinct family of medium to large bipedal, carnivorous allosauroid theropod dinosaurs from the Late Jurassic. Allosauridae is a fairly old taxonomic group, having been first named by the American paleontologist Othniel Charles Marsh in 1878. Allosaurids are characterized by an astragalus with a restriction of the ascending process to the lateral part of the bone, a larger medial than lateral condyle, and a horizontal groove across the face of the condyles.
Elaphrosaurus is a genus of ceratosaurian theropod dinosaur that lived approximately 154 to 150 million years ago during the Late Jurassic Period in what is now Tanzania in Africa. Elaphrosaurus was a medium-sized but lightly built member of the group that could grow up to 6.2 m (20 ft) long. Morphologically, this dinosaur is significant in two ways. Firstly, it has a relatively long body but is very shallow-chested for a theropod of its size. Secondly, it has very short hindlimbs in comparison with its body. Phylogenetic analyses indicate that this genus is likely a ceratosaur. Earlier suggestions that it is a late surviving coelophysoid have been examined but generally dismissed. Elaphrosaurus is currently believed to be a very close relative of Limusaurus, an unusual beaked ceratosaurian which may have been either herbivorous or omnivorous.
Xinjiangovenator is a genus of coelurosaurian dinosaurs, possibly part of the group Maniraptora, which lived during the Early Cretaceous period, sometime between the Valanginian and Albian stages. The remains of Xinjiangovenator were found in the Lianmuqin Formation of Wuerho, Xinjiang, China, and were first described by Dong Zhiming in 1973. The genus is based on a single specimen, an articulated partial right lower leg, containing the tibia, three pieces of the fibula, the calcaneum and the astragalus. This specimen, IVPP V4024-2, is the holotype of the genus.
Dryptosaurus is a genus of basal eutyrannosaurian theropod dinosaur that lived on the island continent of Appalachia approximately 67.6 million years ago during the end of the Maastrichtian age of the Late Cretaceous period. Dryptosaurus was a large, bipedal, ground-dwelling carnivore that could grow up to 7.5 metres (25 ft) long and weigh up to 756–1,500 kilograms (1,667–3,307 lb). Although it is now largely unknown outside of academic circles, the famous 1897 painting of the genus by Charles R. Knight made Dryptosaurus one of the more widely known dinosaurs of its time, in spite of its poor fossil record. First described by Edward Drinker Cope in 1866 and later renamed by Othniel Charles Marsh in 1877, Dryptosaurus is among the first theropod dinosaurs ever known to science.
Quilmesaurus is a genus of carnivorous abelisaurid theropod dinosaur from the Patagonian Upper Cretaceous of Argentina. It was a member of Abelisauridae, closely related to genera such as Carnotaurus. The only known remains of this genus are leg bones which share certain similarities to a variety of abelisaurids. However, these bones lack unique features, which may render Quilmesaurus a nomen vanum.
Sarcosaurus is a genus of basal neotheropod dinosaur, roughly 3.5 metres (11 ft) long. It lived in what is now England and maybe Ireland and Scotland during the Hettangian-Sinemurian stages of the Early Jurassic, about 199-196 million years ago. Sarcosaurus is one of the earliest known Jurassic theropods, and one of only a handful of theropod genera from this time period. Along with Dracoraptor hanigani it is one of the two described neotheropods from the lowermost Jurassic of the United Kingdom.
Magnosaurus was a genus of theropod dinosaur from the Middle Jurassic of England. It is based on fragmentary remains and has often been confused with or included in Megalosaurus.
Condorraptor is an extinct genus of megalosauroid theropod dinosaur. Its genus name means 'robber from Cerro Condor', referencing a nearby village, while its species name, currumili, is named after Hipolito Currumil, the landowner and discoverer of the locality. It was among the earliest large South American theropods, having been found in Lower Jurassic strata of the Cañadón Asfalto Formation in the Cañadón Asfalto Basin of Argentina. The type species, described in 2005, is Condorraptor currumili. It is based on a tibia, with an associated partial skeleton that may belong to the same individual. Initially described as a basal tetanuran, Benson (2010) found it to be a piatnitzkysaurid megalosauroid and the sister taxon of Piatnitzkysaurus, a finding supported by later studies.
Berberosaurus is a genus of neotheropod dinosaur, possibly a ceratosaur, from the Toarcian-age "Toundoute Continental Series" found in the Central High Atlas of Toundoute, Ouarzazate, Morocco. The type species of the genus Berberosaurus is B. liassicus, in reference to the Lias epoch. Berberosaurus might be the oldest known ceratosaur, and is based on partial postcranial remains. This genus represents the oldest formally identified theropod from the North of Africa, as well one of the few from the region in the Early Jurassic.
Glacialisaurus is a genus of sauropodomorph dinosaur. It lived during the Pliensbachian stage of the Early Jurassic period around 186 to 182 million years ago in what is now the central region of the Transantarctic Mountains of Antarctica. It is known from two specimens; the holotype, a partial tarsus (ankle) and metatarsus, and a partial left femur. The fossils were collected by a team led by paleontologist William R. Hammer during a 1990–91 field expedition to the Hanson Formation of Antarctica. They were described in 2007, and made the basis of the new genus and species Glacialisaurus hammeri. The genus name translates as “icy” or "frozen lizard”, and the species name honors Hammer.
Duriavenator is a genus of theropod dinosaur that lived in what is now England during the Middle Jurassic, about 168 million years ago. In 1882, upper and lower jaw bones of a dinosaur were collected near Sherborne in Dorset, and Richard Owen considered the fossils to belong to the species Megalosaurus bucklandii, the first named non-bird dinosaur. By 1964, the specimen was recognised as belonging to a different species, and in 1974 it was described as a new species of Megalosaurus, M. hesperis; the specific name means 'the West' or 'western'. Later researchers questioned whether the species belonged to Megalosaurus, in which many fragmentary theropods from around the world had historically been placed. After examining the taxonomic issues surrounding Megalosaurus, Roger B. J. Benson moved M. hesperis to its own genus in 2008, Duriavenator; this name means "Dorset hunter".
Kayentavenator is a genus of small carnivorous tetanuran dinosaur that lived during the Early Jurassic Period; fossils were recovered from the Kayenta Formation of northeastern Arizona and were described in 2010.
Zuolong is an extinct genus of tetanuran theropod from the Late Jurassic period of China. The type and only species is Z. salleei. The generic name of Zuolong is in honor of General Zuo Zōngtáng with the Chinese word "long" which means dragon. The specific epithet "salleei" is in honor of Hilmar Sallee, who funded the expedition which led to the specimen's discovery.
Piatnitzkysauridae is an extinct family of megalosauroid or basal allosauroid dinosaurs. It only consists of three to four known dinosaur genera: Condorraptor, Marshosaurus, Piatnitzkysaurus and possibly Xuanhanosaurus. The most complete and well known member of this family is Piatnitzkysaurus, which also gives the family its name.
The Charmouth Mudstone Formation is a geological formation in England, dating to the Early Jurassic (Sinemurian–Pliensbachian). It forms part of the lower Lias Group. It is most prominently exposed at its type locality in cliff section between Lyme Regis and Charmouth but onshore it extends northwards to Market Weighton, Yorkshire, and in the subsurface of the East Midlands Shelf and Wessex Basin. The formation is notable for its fossils, including those of ammonites and marine reptiles and rare dinosaur remains. The formation played a prominent role in the history of early paleontology, with its Lyme Regis-Charmouth exposure being frequented by fossil collectors including Mary Anning.