Magnosaurus

Last updated

Contents

Magnosaurus
Temporal range: Bajocian,
~169.7–169.5  Ma
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
↓
Magnosaurus OUMNH J. 12143.png
Skeletal diagram of the holotype specimen
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family:† Megalosauridae
Subfamily:† Afrovenatorinae
Genus:† Magnosaurus
Huene, 1932
Type species
†Megalosaurus nethercombensis
Huene, 1923
Species
  • †M. nethercombensis(Huene, 1923 [originally Megalosaurus ])

Magnosaurus (meaning 'large lizard') 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 .

History and taxonomy

Life restoration Magnosaurus.jpg
Life restoration

In 1923, Friedrich von Huene named Megalosaurus nethercombensis from a partial skeleton (OUM J12143) from the Bajocian age [1] Middle Jurassic Inferior Oolite, found in the nineteenth century by W. Parker near Nethercomb, north of Sherborne, in Dorset, England. The material included partial dentaries, dorsal and caudal vertebrae, a partial ilium, a partial right pubis, internal casts of the femora, and tibiae, from a possible juvenile individual. Huene interpreted it as a more primitive species of Megalosaurus . [2]

In 1926, he named the tooth species Megalosaurus lydekkeri for a specimen, BMNH 41352, from the Lower Lias (Lower Jurassic) of England that Richard Lydekker had first described in 1888. [3] [4] Finally, in 1932, he created the genus Magnosaurus for M. nethercombensis, referred M. lydekkeri to it, and created a third species, M. woodwardi, for the genus. M. woodwardi was based on a tibia (BMNH R.3542) from the Lower Lias, which he simultaneously and accidentally also named Sarcosaurus andrewsi ; [5] in 1956 the latter name was given priority by von Huene. Even more confusing, in the same 1932 publication von Huene renamed Sarcosaurus woodi into Magnosaurus woodi.

Until the 1990s, the genus had been ignored as a species of Megalosaurus. [6] However, with growing concern over what exactly is constituted by Megalosaurus, Magnosaurus has been generally separated as its own genus. [7] [8] [9] Also, there are morphological differences: for example, possible Megalosaurus tibiae are compressed at the far end, unlike those of Magnosaurus. [9] Rauhut (2003) considered it and Eustreptospondylus to be the same genus, because the two share a similarly expanded front tip of the dentary and enlarged third dentary tooth. He therefore renamed Eustreptospondylus oxoniensis a Magnosaurus oxoniensis but this has not been generally followed. [8] Reviews have found it to most likely be a basal tetanuran, probably a megalosaurid. [9] [10] [11] A detailed redescription by Roger Benson in 2010 concluded Magnosaurus was valid taxon, a megalosaurid megalosauroid, and at about 175 million years old the oldest certain known member of the Tetanurae. [12]

Species

Magnosaurus is known from many species, most of were originally named as a different genus. [13]

The type species of Eustreptospondylus, Megalosaurus and Sarcosaurus are also sometimes assigned to Magnosaurus. In such cases the combinations are:

Description

Size of Magnosaurus (in green) compared to two other afrovenatorines Afrovenatorinae Size Comparison by PaleoGeek.svg
Size of Magnosaurus (in green) compared to two other afrovenatorines

Because the remains are sparse and fragmentary, most details about its anatomical features are unknown. It would have been a bipedal carnivore of moderate size for a dinosaur. The most similar animals to it would probably be Eustreptospondylus, Dubreuillosaurus , and Afrovenator . [9] Paul (1988) roughly estimated the mass of the type individual as around 175 kg (386 lb), which would correspond to a length of roughly four metres (13.1 ft), judging by his estimates for the sizes of other theropods. [10] Benson however, in 2010 gave a higher estimation of about half a tonne; the animal would have stood at over a metre at the hip.

Classification

The phylogenetic position of Magnosaurus according to Carrano et al. (2012) is shown by this cladogram: [15]

Megalosauroidea

Related Research Articles

<i>Megalosaurus</i> Genus of Jurassic-aged theropod dinosaur

Megalosaurus is an extinct genus of large carnivorous theropod dinosaurs of the Middle Jurassic Epoch of southern England. Although fossils from other areas have been assigned to the genus, the only certain remains of Megalosaurus come from Oxfordshire and date to the late Middle Jurassic.

<span class="mw-page-title-main">Carnosauria</span> Extinct group of theropod dinosaurs

Carnosauria is an extinct group of carnivorous theropod dinosaurs that lived during the Jurassic and Cretaceous periods.

<i>Afrovenator</i> Extinct genus of dinosaurs

Afrovenator is a genus of megalosaurid theropod dinosaur from the Middle or Late Jurassic Period on the Tiourarén Formation and maybe the Irhazer II Formation of the Niger Sahara region in northern Africa. Afrovenator represents the only properly identified Gondwanan megalosaur, with proposed material of the group present in the Late Jurassic on Tacuarembó Formation of Uruguay and the Tendaguru Formation of Tanzania.

<i>Iliosuchus</i> Extinct genus of dinosaurs

Iliosuchus is a genus of theropod dinosaur known from Bathonian–age rocks of England. It was perhaps 2 metres (6.6 ft) long.

<i>Metriacanthosaurus</i> Metriacanthosaurid theropod dinosaur genus from Middle Jurassic period

Metriacanthosaurus is a genus of metriacanthosaurid dinosaur from the upper Oxford Clay of England, dating to the Late Jurassic period, about 160 million years ago.

<i>Altispinax</i> Genus of dinosaurs (fossil)

Altispinax is a genus of large predatory theropod dinosaur from the Early Cretaceous period of what is now the Wadhurst Clay Formation of East Sussex, England.

<i>Eustreptospondylus</i> Extinct genus of dinosaurs

Eustreptospondylus is a genus of megalosaurid theropod dinosaur, from the Oxfordian stage of the Late Jurassic period in southern England, at a time when Europe was a series of scattered islands.

<span class="mw-page-title-main">Megalosauridae</span> Extinct family of dinosaurs

Megalosauridae is a monophyletic family of carnivorous theropod dinosaurs within the group Megalosauroidea. Appearing in the Middle Jurassic, megalosaurids were among the first major radiation of large theropod dinosaurs. They were a relatively primitive group of basal tetanurans containing two main subfamilies, Megalosaurinae and Afrovenatorinae, along with the basal genus Eustreptospondylus, an unresolved taxon which differs from both subfamilies.

<i>Piatnitzkysaurus</i> Extinct genus of dinosaurs

Piatnitzkysaurus is a genus of megalosauroid theropod dinosaur that lived approximately 179 to 177 million years ago during the lower part of the Jurassic Period in what is now Argentina. Piatnitzkysaurus was a moderately large, lightly built, bipedal, ground-dwelling carnivore that could grow up to 6.6 m (21.7 ft) long.

<span class="mw-page-title-main">Megalosauroidea</span> Extinct superfamily of Dinosaurs

Megalosauroidea is a superfamily of tetanuran theropod dinosaurs that lived from the Middle Jurassic to the Late Cretaceous period. The group is defined as Megalosaurus bucklandii and all taxa sharing a more recent common ancestor with it than with Allosaurus fragilis or Passer domesticus. Members of the group include Spinosaurus, Megalosaurus, and Torvosaurus. They are possibly paraphyletic in nature with respect to Allosauroidea.

<i>Sarcosaurus</i> Extinct genus of dinosaurs

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.

Chuandongocoelurus is a genus of carnivorous tetanuran theropod dinosaur from the Jurassic of China.

<i>Szechuanosaurus</i> Extinct genus of dinosaurs

Szechuanosaurus is an extinct genus of carnivorous theropod dinosaur from the Late Jurassic. Fossils referred to the genus have been found in China, Asia in the Oxfordian-?Tithonian. Its type species is based on several undiagnostic teeth from the Kuangyuan Series. Additional possible specimens of Szechuanosaurus were also reported from the Kalaza Formation, also located in China.

<i>Dubreuillosaurus</i> Extinct genus of dinosaurs

Dubreuillosaurus is a genus of carnivorous dinosaur from the middle Jurassic Period. It is a megalosaurid theropod. Its fossils were found in France. The only named species, Dubreuillosaurus valesdunensis, was originally described as a species of Poekilopleuron, Poekilopleuron? valesdunensis, which is still formally the type species of the genus. It was later renamed Dubreuillosaurus valesdunensis when, in 2005, Allain came to the conclusion that it was not part of the genus Poekilopleuron. Its type specimen, MNHN 1998-13, is only rivalled in the number of preserved elements in this group by that of Eustreptospondylus. Dubreuillosaurus is considered to be the sister species of Magnosaurus. It did not show signs of insular dwarfism even though it was uncovered on an island.

<i>Erectopus</i> Extinct species of reptile

Erectopus is an extinct genus of basal allosauroid theropod from the Early Cretaceous La Penthiève Beds Formation of France and also possibly the Cernavodă Formation of southern Romania. The type species is E. superbus, which was initially known as a species of Megalosaurus.

<i>Kaijiangosaurus</i> Extinct genus of dinosaurs

Kaijiangosaurus is a genus of carnivorous tetanuran theropod dinosaur from the Middle Jurassic of China. In 1984 He Xinlu named and described the type species Kaijiangosaurus lini. The generic name refers to the River (jiang) Kai. The specific name honours the paleontologist Lin Wenqiu.

<i>Piveteausaurus</i> Extinct genus of dinosaurs

Piveteausaurus is a genus of theropod dinosaur known from a partial skull discovered in the Middle Jurassic Marnes de Dives formation of Calvados, in northern France and lived about 164.7-161.2 million years ago. In 2012 Thomas Holtz gave a possible length of 11 meters.

<i>Streptospondylus</i> Extinct genus of dinosaurs

Streptospondylus is a genus of tetanuran theropod dinosaur known from the Late Jurassic period of France, 161 million years ago. It was a medium-sized predator with an estimated length of 6 meters (19.5 ft) and a weight of 500 kg (1,100 lbs).

<i>Duriavenator</i> Genus of theropod dinosaur

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".

<span class="mw-page-title-main">Piatnitzkysauridae</span> Extinct family of dinosaurs

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.

References

  1. ↑ Ogg, J. G.; Hinnov, L. A. (2012). "Jurassic". In Gradstein, Felix M.; Ogg, Gabi M.; Ogg, J. G.; Schmitz, Mark D. (eds.). The Geologic Time Scale 2012. Vol. 2. Contributor: Huang, C. A. Elsevier Science. pp. 731–790. ISBN   9780444594488.
  2. ↑ von Huene, F. (1923). Carnivorous Saurischia in Europe since the Triassic. Bulletin of the Geological Society of America 34:449-458.
  3. ↑ von Huene, F. (1926). The carnivorous Saurischia in the Jura and Cretaceous formations, principally in Europe. Revista del Museo de La Plata 29:35-167.
  4. ↑ Lydekker, R. (1888). Catalogue of the Fossil Reptilia and Amphibia in the British Museum (Natural History). Part I. Containing the Orders Ornithosauria, Crocodilia, Dinosauria, Squamata, Rhynchocephalia, and Proterosauria. British Museum (Natural History):London, 309 p.
  5. ↑ von Huene, F. (1932). Die fossile Reptil-Ordnung Saurischia, ihre Entwicklung und Geschichte. Monographien zur Geologie und Palaeontologie 1(4) [German]
  6. ↑ Waldman, M. (1974). "Megalosaurids from the Bajocian (Middle Jurassic) of Dorset". Palaeontology 17(2):325-339.
  7. ↑ Molnar, R.E., Kurzanov, S.M., and Dong, Z. (1990). "Carnosauria". In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.), The Dinosauria. University of California Press:Berkeley and Los Angeles, p. 169-209. ISBN   0-520-06727-4
  8. 1 2 Rauhut, O.W.M. (2003). "The Interrelationships and Evolution of Basal Theropod Dinosaurs." Special Papers in Palaeontology 69. The Palaeontological Association:London, 213 p.
  9. 1 2 3 4 5 Holtz Jr., T.R., Molnar, R.E., and Currie, P.J. (2004). "Basal Tetanurae". In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.), The Dinosauria (second edition). Berkeley: University of California Press:Berkeley, p. 71-110. ISBN   0-520-24209-2
  10. 1 2 Paul, G.S. (1988). Predatory Dinosaurs of the World. Simon & Schuster:New York, 464 p. ISBN   0-671-61946-2
  11. ↑ Benson, R.B.J. (2010). "A description of Megalosaurus bucklandii (Dinosauria: Theropoda) from the Bathonian of the UK and the relationships of Middle Jurassic theropods". Zoological Journal of the Linnean Society. 158 (4): 882–935. doi: 10.1111/j.1096-3642.2009.00569.x .
  12. ↑ Benson, Roger B. J. (2010-03-15). "The osteology of Magnosaurus nethercombensis (Dinosauria, Theropoda) from the Bajocian (Middle Jurassic) of the United Kingdom and a re-examination of the oldest records of tetanurans". Journal of Systematic Palaeontology. 8 (1): 131–146. doi: 10.1080/14772011003603515 . ISSN   1477-2019. S2CID   140198723.
  13. 1 2 Weishampel, D.B.; Dodson, P.; Osmolska, H. (eds.). "The Dinosauria: Second Edition". Berkeley: University of California Press, p 99. ISBN   0-520-24209-2.
  14. ↑ Carrano, M.T., and Sampson, S.D. (2004). A review of coelophysoids (Dinosauria: Theropoda) from the Early Jurassic of Europe, with comments on the late history of the Coelophysoidea. Neues Jahrbuch für Geologie und Paläontologie - Monatshefte 2004(9):537-558.
  15. ↑ M.T. Carrano, R.B.J. Benson, and S.D. Sampson, 2012, "The phylogeny of Tetanurae (Dinosauria: Theropoda)", Journal of Systematic Palaeontology10(2): 211-300
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.