Coeluridae

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Coelurids
Temporal range: Late Jurassic, 153–150  Ma
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Tanycolagreus.jpg
Tanycolagreus fossil cast, North American Museum of Ancient Life.
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Clade: Tyrannoraptora
Family: Coeluridae
Marsh, 1881
Genera

Coeluridae is a historically unnatural group of generally small, carnivorous dinosaurs from the late Jurassic Period. For many years, any small Jurassic or Cretaceous theropod that did not belong to one of the more specialized families recognized at the time was classified with the coelurids, creating a confusing array of 'coelurid' theropods that were not closely related. Although they have been traditionally included in this family, there is no evidence that any of these primitive coelurosaurs form a natural group with Coelurus , the namesake of Coeluridae, to the exclusion of other traditional coelurosaur groups.

Classification

Before the use of phylogenetic analyses, Coeluridae and Coelurosauria were taxonomic wastebaskets used for small theropods that did not belong to other groups; thus, they accumulated many dubious genera. [1] [2] As late as the 1980s, popular books recognized over a dozen "coelurids", including such disparate forms as the noasaurid Laevisuchus and the oviraptorosaurian Microvenator , and considered them descendants of the coelophysids. [3] A wastebasket Coeluridae lingered into the early 1990s in some sources [4] (and appears in at least one 2006 source) [5] but since then it has only been recognized in a much reduced form. [6] [7]

In 2003, O.W.M. Rauhut, using a cladistic analysis, found Coeluridae to include Coelurus (Late Jurassic, North America), Compsognathus (Late Jurassic, Europe), Sinosauropteryx (Early Cretaceous, Asia) and an unnamed Compsognathus -like form (Early Cretaceous, South America; this dinosaur has since been placed in the new genus Mirischia ). Rauhut considered coelurids to be a monophyletic group of basal coelurosaurs, characterized by evolutionary reversals in some aspects of the vertebrae to the more primitive theropod condition. [6] However, he and other authors have not since found this result. [7] [8] [9] Phil Senter proposed in 2007 that Coelurus and Tanycolagreus were the only coelurids, and were actually tyrannosauroids. [7]

Coeluridae received a formal phylogenetic definition in 2015, when it was defined as all species more closely related to Coelurus fragilis than to Proceratosaurus bradleyi, Tyrannosaurus rex, Allosaurus fragilis, Compsognathus longipes, Ornithomimus edmontonicus, or Deinonychus antirrhopus by Hendrickx, Hartman and Mateus. [10] It remains unclear whether or not this group contains any species other than Coelurus itself, and while Tanycolagreus is often included, support for this relationship has been weak in most of the studies that recovered it. [11]

Below is a cladogram placing Coelurus in Coelurosauria by Cau et al. in 2015. [12]

Coelurosauria

Related Research Articles

<span class="mw-page-title-main">Coelurosauria</span> Clade of dinosaurs

Coelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs.

<span class="mw-page-title-main">Tetanurae</span> Clade containing most theropod dinosaurs

Tetanurae is a clade that includes most theropod dinosaurs, including megalosauroids, allosauroids, tyrannosauroids, ornithomimosaurs, compsognathids and maniraptorans. Tetanurans are defined as all theropods more closely related to modern birds than to Ceratosaurus and contain the majority of predatory dinosaur diversity. Tetanurae likely diverged from its sister group, Ceratosauria, during the late Triassic. Tetanurae first appeared in the fossil record by the Early Jurassic about 190 mya and by the Middle Jurassic had become globally distributed.

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

Ornitholestes is a small theropod dinosaur of the late Jurassic of Western Laurasia.

Coelurus is a genus of coelurosaurian dinosaur from the Late Jurassic period. The name means "hollow tail", referring to its hollow tail vertebrae. Although its name is linked to one of the main divisions of theropods (Coelurosauria), it has historically been poorly understood, and sometimes confused with its better-known contemporary Ornitholestes. Like many dinosaurs studied in the early years of paleontology, it has had a confusing taxonomic history, with several species being named and later transferred to other genera or abandoned. Only one species is currently recognized as valid: the type species, C. fragilis, described by Othniel Charles Marsh in 1879. It is known from one partial skeleton found in the Morrison Formation of Wyoming, United States. It was a small bipedal carnivore with elongate legs.

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

Proceratosaurus is a genus of carnivorous theropod dinosaur from the Middle Jurassic (Bathonian) of England. It contains a single species. P. bradleyi, known from a mostly complete skull and lower jaws. Proceratosaurus was a small dinosaur, estimated to measure around 3 m (9.8 ft) in length. Its name refers to how it was originally thought to be an ancestor of Ceratosaurus, due to the partially preserved portion of the crest of Proceratosaurus superficially resembling the small crest of Ceratosaurus. Now, however, it is considered a coelurosaur, specifically a member of the family Proceratosauridae, and amongst the earliest known members of the clade Tyrannosauroidea.

Chingkankousaurus is a genus of theropod dinosaur containing the single species Chingkankousaurus fragilis. C. fragilis is known only from a single fossilized bone fragment from the late Cretaceous Period Wangshi Series of Shandong province in eastern China.

<i>Elaphrosaurus</i> Ceratosaurian theropod dinosaur genus from the Late Jurassic Period

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.

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

Siamotyrannus is a genus of theropod dinosaur from the early Cretaceous of Thailand.

<span class="mw-page-title-main">Tyrannosauroidea</span> Extinct superfamily of dinosaurs

Tyrannosauroidea is a superfamily of coelurosaurian theropod dinosaurs that includes the family Tyrannosauridae as well as more basal relatives. Tyrannosauroids lived on the Laurasian supercontinent beginning in the Jurassic Period. By the end of the Cretaceous Period, tyrannosauroids were the dominant large predators in the Northern Hemisphere, culminating in the gigantic Tyrannosaurus. Fossils of tyrannosauroids have been recovered on what are now the continents of North America, Europe and Asia, with fragmentary remains possibly attributable to tyrannosaurs also known from South America and Australia.

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

Calamosaurus was a genus of small theropod dinosaur from the Barremian-age Lower Cretaceous Wessex Formation of the Isle of Wight, England. It is based on two cervical vertebrae, collected by Reverend William Fox.

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

<i>Tanycolagreus</i> Extinct genus of reptiles

Tanycolagreus is a genus of coelurosaurian theropod from the Late Jurassic of North America.

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

Allosauroidea is a superfamily or clade of theropod dinosaurs which contains four families — the Metriacanthosauridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae. Allosauroids, alongside the family Megalosauroidea, were among the apex predators that were active during the Middle Jurassic to Late Cretaceous periods. The most famous and best understood allosauroid is the North American genus Allosaurus.

Thomas Richard Holtz Jr. is an American vertebrate palaeontologist, author, and principal lecturer at the University of Maryland's Department of Geology. He has published extensively on the phylogeny, morphology, ecomorphology, and locomotion of terrestrial predators, especially on tyrannosaurids and other theropod dinosaurs. He wrote the book Dinosaurs and is the author or co-author of the chapters "Saurischia", "Basal Tetanurae", and "Tyrannosauroidea" in the second edition of The Dinosauria. He has also been consulted as a scientific advisor for the Walking with Dinosaurs BBC series as well as the Discovery special When Dinosaurs Roamed America, and has appeared in numerous documentaries focused on prehistoric life, such as Jurassic Fight Club on History and Monsters Resurrected, Dinosaur Revolution and Clash of the Dinosaurs on Discovery.

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

Compsognathidae is a family of coelurosaurian theropod dinosaurs. Compsognathids were small carnivores, generally conservative in form, hailing from the Jurassic and Cretaceous Periods. The bird-like features of these species, along with other dinosaurs such as Archaeopteryx inspired the idea for the connection between dinosaur reptiles and modern-day avian species. Compsognathid fossils preserve diverse integument — skin impressions are known from four genera commonly placed in the group, Compsognathus, Sinosauropteryx, Sinocalliopteryx, and Juravenator. While the latter three show evidence of a covering of some of the earliest primitive feathers over much of the body, Juravenator and Compsognathus also show evidence of scales on the tail or hind legs. "Ubirajara jubatus", informally described in 2020, had elaborate integumentary structures on its back and shoulders superficially similar to the display feathers of a standardwing bird-of-paradise, and unlike any other non-avian dinosaur currently described.

<span class="mw-page-title-main">Maniraptoriformes</span> Clade of dinosaurs

Maniraptoriformes is a clade of dinosaurs with pennaceous feathers and wings that contains ornithomimosaurs and maniraptorans. This group was named by Thomas Holtz, who defined it as "the most recent common ancestor of Ornithomimus and birds, and all descendants of that common ancestor."

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

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

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

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 Zu 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.

<span class="mw-page-title-main">Orionides</span> Clade of dinosaurs

Orionides is a clade of tetanuran theropod dinosaurs from the Middle Jurassic to the Present. The clade includes most theropod dinosaurs, including birds.

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

Sciurumimus is an extinct genus of tetanuran theropod from the Late Jurassic Torleite Formation of Germany. It is known from a single juvenile specimen representing the type species, Sciurumimus albersdoerferi, which was found in a limestone quarry close to Painten in Lower Bavaria. The specimen was preserved with traces of feather-like filaments.

References

  1. Paul, G.S. (1988). Predatory Dinosaurs of the World. New York: Simon and Schuster. pp.  248–250. ISBN   0-671-61946-2.
  2. Norman, David B. (1990). "Problematic theropoda: "coelurosaurs"". In Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (eds.). The Dinosauria. Berkeley: University of California Press. pp. 280–305. ISBN   0-520-06727-4.
  3. Lambert, David; the Diagram Group (1983). "Coelurids". A Field Guide to Dinosaurs. New York: Avon Books. pp.  44–47. ISBN   0-380-83519-3.
  4. Lessem, Don; Glut, Donald F. (1993). The Dinosaur Society Dinosaur Encyclopedia. Random House, Inc. ISBN   0-679-41770-2.
  5. Palmer, Douglas (2006). "Ruling Reptiles: Dinosaurs and Their Kin". The Illustrated Encyclopedia of the Prehistoric World. New Jersey: Chartwell Books, Inc. pp. 232–313. ISBN   0-7858-2086-8.
  6. 1 2 Rauhut, Oliver W.M. (2003). "The interrelationships and evolution of basal theropod dinosaurs". Special Papers in Palaeontology. 69: 1–213.
  7. 1 2 3 Senter, Phil (2007). "A new look at the phylogeny of Coelurosauria (Dinosauria, Theropoda)". Journal of Systematic Palaeontology. 5 (4): 429–463. doi:10.1017/S1477201907002143. S2CID   83726237.
  8. Holtz, Thomas R. Jr.; Molnar, Ralph E.; Currie, Philip J. (2004). Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (eds.). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp.  71–110. ISBN   0-520-24209-2.
  9. Rauhut, Oliver W.M.; Xu, Xing (2005). "The small theropod dinosaurs Tugulusaurus and Phaedrolosaurus from the Early Cretaceous of Xinjiang, China". Journal of Vertebrate Paleontology. 25 (1): 107–118. doi:10.1671/0272-4634(2005)025[0107:TSTDTA]2.0.CO;2.
  10. Hendrickx, C.; Hartman, S. A.; Mateus, O. (2015). "An Overview Of Non-Avian Theropod Discoveries And Classification". PalArch's Journal of Vertebrate Palaeontology. 12 (1): 1–73.
  11. Brusatte, S. L., & Carr, T. D. (2016). The phylogeny and evolutionary history of tyrannosauroid dinosaurs. Scientific Reports, 6.
  12. Cau, Andrea; Brougham, Tom; Naish, Darren (2015). "The phylogenetic affinities of the bizarre Late Cretaceous Romanian theropod Balaur bondoc (Dinosauria, Maniraptora): Dromaeosaurid or flightless bird?". PeerJ. 3: e1032. doi: 10.7717/peerj.1032 . PMC   4476167 . PMID   26157616.