Nuthetes

Nuthetes is the name given to a dubious, possibly dromaeosaurid, genus of theropod dinosaur, known only from fossil teeth and jaw fragments found in rocks of the middle Berriasian (Early Cretaceous) age in the Cherty Freshwater Member of the Lulworth Formation in England. As a dromaeosaurid Nuthetes would have been a small predator, about two metres long.

Nuthetes
Temporal range: Early Cretaceous, 143 Ma
Nuthetes
Portions of the holotype mandible and close up of a tooth
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Saurischia
Suborder: Theropoda
Family: Dromaeosauridae
Genus: Nuthetes
Owen, 1854
Species:
N. destructor
Binomial name
Nuthetes destructor
Owen, 1854
Synonyms

Megalosaurus destructor (Owen, 1854)

Naming

The genus Nuthetes contains one species (the type species), Nuthetes destructor. N. destructor was named and described by Richard Owen in 1854.[1] The generic name Nuthetes is derived from the Koine Greek nouthetes, a contraction of νουθέτητης (nouthetetes) meaning "one who admonishes" or "a monitor," in reference to the similarity of Nuthetes teeth to those of a modern monitor lizard.[2] The specific name is Latin for "destroyer", a reference to "the adaptations of the teeth for piercing, cutting, and lacerating the prey" of a form he estimated to be equal in size to the present Bengal monitor.[3]

History

The holotype, DORCM G 913, was collected by Charles Willcox, an amateur paleontologist living at Swanage, from the Feather Quarry near Durlston Bay in a marine deposition of Cherty Freshwater Member of the Lulworth Formation, dating from the middle Berriasian. It consists of an about three inch long left dentary fragment with nine teeth. The holotype was once thought to be lost but was rediscovered in the seventies in the Dorset County Museum. Later several other teeth and specimen BMNH 48207, another dentary fragment from a somewhat smaller individual, were referred to the species. Owen in 1878 also assumed some fossilised scutes, of a type for which he coined the name "granicones",[4] belonged to Nuthetes but these were in 2002 shown to be limb or tail osteoderms of a turtle, possibly "Helochelydra" anglica or "H." bakewelli.[5]

In 2006 a tooth from France found in Charente, specimen CHEm03.537, was referred to a Nuthetes sp.[6]

Classification

Purbeck lagoon
Restoration of Nuthetes (centre) capturing Durlstotherium

Nuthetes was originally classified by Owen as a lizard and a varanid; later he changed his mind concluding it was a crocodilian.[7] Only in 1888 Richard Lydekker understood it was a dinosaur. In 1934 William Elgin Swinton thought it was a juvenile member of the Megalosauridae. In 1970 Rodney Steel even renamed the species Megalosaurus destructor. In 2002 however, a re-examination of the fossils by paleontologist Angela Milner showed that they most likely belonged to a subadult dromaeosaurid.[8] Steve Sweetman examined five good specimens of fossil teeth and confirmed that they belong to Nuthetes destructor, and concluded that this species is a velociraptorine dromaeosaurid. If this placement is correct, it would have been one of the oldest dromaeosaurids known, the first to be described, and the first known from Britain.[9] However, Rauhut, Milner and Moore-Fay (2010) pointed out the great similarity of the teeth of basal tyrannosauroid Proceratosaurus to the teeth of velociraptorine dromaeosaurids. The authors recommended caution when referring isolated teeth from the Late Jurassic or Early Cretaceous to the Dromaeosauridae (explicitly citing Milner's 2002 study and Sweetman's 2004 study as examples of studies that identified isolated theropod teeth as belonging to dromaeosaurids), as these teeth might belong to proceratosaurid tyrannosauroids instead.[10]

Some large specimens referred to Nuthetes may instead belong to Dromaeosauroides.[11]

See also

References

  1. ^ Owen, R., 1854, "On some fossil reptilian and mammalian remains from the Purbecks", Quarterly Journal of the Geological Society of London, 10: 420-43
  2. ^ Glut, D.F. (2002). Dinosaurs: The Encyclopedia Supplement 2. McFarland & Company, 686 pp. ISBN 978-0-7864-1166-5
  3. ^ Owen, R., 1861, "Monograph on the fossil Reptilia of the Wealden and Purbeck formations. Part V. Lacertilia (Nuthetes, etc.)", The Palaeontological Society, London 1858: 31-39
  4. ^ Owen, R., 1878, "On the fossils called 'granicones'; being a contribution to the histology of the exo-skeleton in 'Reptilia'", Journal of the Microscopical Society, 1: 233-236
  5. ^ Barrett, P. M., Clarke, J. B., Brinkman, D. B., Chapman, S. D., and Ensom, P. C., 2002, "Morphology, histology and identification of 'granicones' from the Purbeck Limestone Formation (Lower Cretaceous: Berriasian) of Dorset, southern England", Cretaceous Research, 23: 279-295
  6. ^ Pouech, Joane; Mazin, Jean-Michel and Billon-Bruyat, Jean-Paul, 2006, "Microvertebrate biodiversity from Cherves-de-Cognac (Lower Cretaceous, Berriasian: Charente, France)", In: 9th International Symposium, Mesozoic Terrestrial Ecosystems and Biota, Manchester 2006, Abstracts and Proceedings volume. p.96-100. View this article online
  7. ^ Owen, R., 1879, "Monograph on the fossil Reptilia of the Wealden and Purbeck formations. Supplement no. IX. Crocodilia (Goniopholis, Brachydectes, Nannosuchus, Theriosuchus, and Nuthetes)", The Palaeontographical Society 1879, 1-19
  8. ^ Milner, A. (2002). "Theropod dinosaurs of the Purbeck Limestone Group, southern England." In: Milner and Batten (eds.). Life and Environment in Purbeck Times. Special Paper in Palaeontology, 68(268): 191-201.
  9. ^ Sweetman, S.C. (2004). "The first record of velociraptorine dinosaurs (Saurischia, Theropoda) from the Wealden (Early Cretaceous, Barremian) of southern England." Cretaceous Research, 25(3): 353-364. doi:10.1016/j.cretres.2004.01.004
  10. ^ Rauhut, Oliver W. M.; Milner, Angela C.; Moore-Fay, Scott (2010). "Cranial osteology and phylogenetic position of the theropod dinosaur Proceratosaurus bradleyi (Woodward, 1910) from the Middle Jurassic of England". Zoological Journal of the Linnean Society. 158 (1): 155–195. doi:10.1111/j.1096-3642.2009.00591.x.
  11. ^ Bonde, N. (2012). "Danish Dinosaurs: A Review". In Godefroit, P. (ed.). Bernissart Dinosaurs. Indiana University Press. pp. 435–449.

External links

1854 in paleontology

Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1854.

Berriasian

In the geological timescale, the Berriasian is an age or stage of the Early Cretaceous. It is the oldest, or lowest, subdivision in the entire Cretaceous. It spanned the time between 145.0 ± 4.0 Ma and 139.8 ± 3.0 Ma (million years ago). The Berriasian succeeds the Tithonian (part of the Jurassic) and precedes the Valanginian.

Dromaeosaurinae

Dromaeosaurinae is a subfamily of Dromaeosauridae. Most dromaeosaurines lived in what is now the United States and Canada, as well as Mongolia, and possibly Denmark as well. Isolated teeth that may belong to African dromaeosaurines have also been discovered in Ethiopia. These teeth date to the Tithonian stage, of the Late Jurassic Period.All North American and Asian dromaeosaurine dinosaurs from the Late Cretaceous were generally small, no more than 1.8 metres (5.9 ft) long, in Dromaeosaurus and Adasaurus. However, among the dromaeosaurines were the largest dromaeosaurs ever; Dakotaraptor was ~5.5 metres (18 ft) long, Achillobator 6 metres (20 ft), and Utahraptor up to ~7 metres (23 ft).

Dromaeosauroides

Dromaeosauroides is a genus of dromaeosaurid theropod dinosaur from the Early Cretaceous of what is now Denmark. It was discovered in the Jydegaard Formation in the Robbedale valley, on the island of Bornholm in the Baltic Sea. This is the only likely place for dinosaur remains to be discovered on Danish territory, since the Mesozoic deposits exposed in the rest of the country are marine. Dromaeosauroides is the first known dinosaur from this location, and the only one which has been scientifically named. It is one of the oldest known dromaeosaurs in the world, and the first known uncontested dromaeosaur from the Early Cretaceous of Europe.

It is known from two teeth, the first of which was found in 2000 and the second in 2008. Based on the first tooth (the holotype), the genus and species Dromaeosauroides bornholmensis was named in 2003. The genus name means "Dromaeosaurus-like", due to the similarity to the teeth of that genus, and the species name means "from Bornholm". After this discovery, remains and tracks of more dinosaurs were found in several formations on Bornholm. Some teeth from the United Kingdom that have been referred to the genus Nuthetes may also belong to this animal. Coprolites containing fish remains found in the Jydegaard Formation may belong to Dromaeosauroides.

The holotype tooth is 21.7 millimetres (0.85 in) long, and the second tooth is 15 millimetres (0.59 in). They are curved and finely serrated. In life, Dromaeosauroides would have been 2 to 3 metres (7 to 10 ft) in length, and weighed about 40 kilograms (88 lb). As a dromaeosaur it would have been feathered, and had a large sickle claw on its feet like its relatives Dromaeosaurus and Deinonychus. It lived in a coastal lagoon environment with sauropods, as evidenced by a possible titanosaur tooth.

Echinodon

Echinodon (pronounced eh-KY-no-don) meaning "hedgehog tooth" in reference to the spines on its teeth (Ancient Greek: εχινος, romanized: echinos, lit. 'hedgehog', + ὀδών, odṓn, 'tooth'), occasionally known as Saurechinodon, is a genus of small European dinosaur of the early Cretaceous Period (Berriasian age), 140 million years ago.

Eudromaeosauria

Eudromaeosauria ("true dromaeosaurs") is a subgroup of terrestrial dromaeosaurid theropod dinosaurs. They were relatively large-bodied, feathered hypercarnivores (with diets consisting almost entirely of other terrestrial vertebrates) that flourished in the Cretaceous Period.

Eudromaeosaur fossils are known almost exclusively from the northern hemisphere. They first appeared in the early Cretaceous Period (early Aptian stage, about 124 million years ago) and survived until the end of the Cretaceous (Maastrichtian stage, 66 Ma). The earliest known definitive eudromaeosaur is the dromaeosaurine Utahraptor ostrommaysorum, from the Cedar Mountain Formation, dated to 124 million years ago. However, the earlier (143-million-year-old) fossils such as those of Nuthetes destructor and several indeterminate teeth dating to the Kimmeridgian stage may represent eudromaeosaurs.

Graciliraptor

Graciliraptor (meaning "graceful thief") is a genus of theropod dinosaur from the early Cretaceous Period. It is a microraptorine dromaeosaurid.

The type species Graciliraptor lujiatunensis was first named and described in 2004 by Xu Xing and Wang Xiaoling. The generic name is derived from Latin gracilis and raptor. The specific name refers to the village Lujiatun where the fossil site is located. Its fossil, holotype IVPP V 13474, was found in Beipiao, Liaoning Province, China.

Hulsanpes

Hulsanpes is a genus of dromaeosaurid theropod dinosaur from Mongolia that lived during the Late Cretaceous.

Itemirus

Itemirus is a genus of theropod dinosaur from the Turonian age of the Late Cretaceous period of Uzbekistan.

Luanchuanraptor

Luanchuanraptor (meaning "Luanchuan thief") is a genus of dromaeosaurid theropod dinosaur from the Late Cretaceous of China. It is based on a partial skeleton from the Qiupa Formation in Luanchuan, Henan. A medium-sized dromaeosaurid, it is the first Asian dromaeosaurid described from outside the Gobi Desert or northeastern China. The fossil material is cataloged as 4HIII-0100 in the Henan Geological Museum and includes four teeth, one frontal, a neck vertebra, one or two back vertebrae, seventeen tail vertebrae, ribs, chevrons, a humerus (upper arm bone), claw and finger bones, partial shoulder and pelvic girdles, and other fragmentary bones from a moderately sized dromaeosaurid. The type species is L. henanensis, described by Lü et al. in 2007.

Proceratosauridae

Proceratosauridae is a family or clade of theropod dinosaurs from the Middle Jurassic to the Early Cretaceous.

Pyroraptor

Pyroraptor (meaning "fire thief") is a genus of dromaeosaurid dinosaur from the Late Cretaceous of what is now southern France, it lived during the late Campanian and early Maastrichtian stages, approximately 70.6 million years ago. It is known from a single partial specimen that was found in Provence in 1992. The animal was named Pyroraptor olympius by Allain and Taquet in 2000.

Saurornitholestinae

Saurornitholestinae is a subfamily of dromaeosaurid dinosaurs. The saurornitholestines currently include three monotypic genera: Atrociraptor marshalli, Bambiraptor feinbergorum, and Saurornitholestes langstoni. All are medium-sized dromaeosaurs from the Late Cretaceous of western North America. The group was originally recognized by Longrich and Currie as the sister taxon to a clade formed by the Dromaeosaurinae and Velociraptorinae. However, not all phylogenetic analyses recover this group.

Theriosuchus

Theriosuchus is an extinct genus of atoposaurid mesoeucrocodylian from Late Jurassic to Early Cretaceous of Europe (southern England), Southeast Asia (Thailand) and western North America (Wyoming), with fragmentary records from Middle Jurassic and Early Cretaceous sites in China, Morocco, and Scotland.

Unenlagiinae

Unenlagiinae is a subfamily of dromaeosaurid theropods. Unenlagiines are known from South America and Antarctica.

Unquillosaurus

Unquillosaurus (meaning "Unquillo river lizard") is a genus of maniraptoran dinosaur from the Late Cretaceous Period, discovered in Argentina. Known only from a single fossilized pubis (a pelvic bone), its total body length may have reached 2 to 3 metres (6.6 to 9.8 ft).

Variraptor

Variraptor ( VARR-i-rap-tor; "Var thief") is a genus of coelurosaurian theropod dinosaur from the Late Cretaceous of France.

Velociraptorinae

Velociraptorinae is a subfamily of the theropod group Dromaeosauridae. The earliest velociraptorines are probably Nuthetes from the United Kingdom, and possibly Deinonychus from North America. However, several indeterminate velociraptorines have also been discovered, dating to the Kimmeridgian stage, in the Late Jurassic Period. These fossils were discovered in the Langenberg quarry, Oker near Goslar, Germany.In 2007 paleontologists studied front limb bones of Velociraptor and discovered small bumps on the surface, known as quill knobs. The same feature is present in some bird bones, and represents the attachment point for strong secondary wing feathers. This finding provided the first direct evidence that velociraptorines, like all other maniraptorans, had feathers.While most velociraptorines were generally small animals, at least one species may have achieved gigantic sizes comparable to those found among the dromaeosaurines. So far, this unnamed giant velociraptorine is known only from isolated teeth found on the Isle of Wight, England. The teeth belong to an animal the size of dromaeosaurines of the genus Utahraptor, but they appear to belong to a velociraptorine, judging by the shape of the teeth and the anatomy of their serrations.

Yurgovuchia

Yurgovuchia is an extinct genus of dromaeosaurid theropod dinosaur known from the Early Cretaceous (probably Barremian stage) of Utah. It contains a single species, Yurgovuchia doellingi. According to a phylogenetic analysis performed by its describers, it represents an advanced dromaeosaurine, closely related to Achillobator, Dromaeosaurus and Utahraptor.

Languages

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.