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Changed that Allosaurids are actually known only from the Jurassic, since Allosaurus and Saurophaganax, the definitive members of the family, lived in the late Jurassic.
 
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{{Automatic taxobox
{{Automatic taxobox
| name = Allosaurids
| name = Allosaurids
| image = Allosaurus SDNHM (1).jpg
| image = CM Allosaurus.jpg
| image_caption = An ''A. fragilis'' skeletal mount, at the [[San Diego Natural History Museum]]
| image_caption = An ''A. fragilis'' skeletal mount, at the [[Carnegie Museum of Natural History]]
| fossil_range = [[Late Jurassic]], {{fossilrange|155|145}}
| fossil_range = [[Late Jurassic]], {{fossilrange|155|145}}
| taxon = Allosauridae
| taxon = Allosauridae
Line 11: Line 11:
| subdivision_ranks = Genera
| subdivision_ranks = Genera
| subdivision_ref = <ref name=tetanurans2012>{{Cite journal | last1 = Carrano | first1 = M. T. | last2 = Benson | first2 = R. B. J. | last3 = Sampson | first3 = S. D. | doi = 10.1080/14772019.2011.630927 | title = The phylogeny of Tetanurae (Dinosauria: Theropoda) | journal = Journal of Systematic Palaeontology | volume = 10 | issue = 2 | pages = 211–300| year = 2012 }}</ref>
| subdivision_ref = <ref name=tetanurans2012>{{Cite journal | last1 = Carrano | first1 = M. T. | last2 = Benson | first2 = R. B. J. | last3 = Sampson | first3 = S. D. | doi = 10.1080/14772019.2011.630927 | title = The phylogeny of Tetanurae (Dinosauria: Theropoda) | journal = Journal of Systematic Palaeontology | volume = 10 | issue = 2 | pages = 211–300| year = 2012 }}</ref>
| subdivision =
| subdivision = *{{extinct}}''[[Allosaurus]]''
*{{extinct}}''[[Allosaurus]]''
*{{extinct}}''[[Antrodemus]]''?
*{{extinct}}''[[Saurophaganax]]''
*{{extinct}}''[[Asfaltovenator]]''?
*{{extinct}}''[[Saurophaganax]]''?
|synonyms =
*{{extinct}}''[[Epanterias]]''?
* Antrodemidae <small>Marsh, 1878</small>
| synonyms = * Antrodemidae <small>Marsh, 1878</small>
* Labrosauridae <small>Marsh, 1882</small>
* Labrosauridae <small>Marsh, 1882</small>
}}
}}


'''Allosauridae''' is a family of medium to large bipedal, [[carnivorous]] [[Allosauroidea|allosauroid]] [[theropod]] [[dinosaurs]] from the Late [[Jurassic]].<ref name=":0">{{Cite journal|last=Carrano|first=Matthew T.|last2=Benson|first2=Roger B. J.|last3=Sampson|first3=Scott D.|date=2012-06-01|title=The phylogeny of Tetanurae (Dinosauria: Theropoda)|journal=Journal of Systematic Palaeontology|volume=10|issue=2|pages=211–300|doi=10.1080/14772019.2011.630927|issn=1477-2019}}</ref> Allosauridae is a fairly old taxonomic group, having been first named by the American paleontologist [[Othniel Charles Marsh]] in 1878.<ref>Marsh, Othniel Charles (1878). "Notice of new dinosaurian reptiles". ''American Journal of Science and Arts''. '''15''': 241–244.</ref> Allosaurids are characterized by an [[Talus bone|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.<ref name=":1">{{Cite journal|last=Molnar|first=R. E.|last2=Flannery|first2=Timothy F.|last3=Rich|first3=Thomas H. V.|date=1981-01-01|title=An allosaurid theropod dinosaur from the Early Cretaceous of Victoria, Australia|journal=Alcheringa: An Australasian Journal of Palaeontology|volume=5|issue=2|pages=141–146|doi=10.1080/03115518108565427|issn=0311-5518}}</ref>
'''Allosauridae''' is an extinct family of medium to large bipedal, [[carnivorous]] [[Allosauroidea|allosauroid]] [[theropod]] [[dinosaurs]] from the Late [[Jurassic]].<ref name=":0">{{Cite journal|last=Carrano|first=Matthew T.|last2=Benson|first2=Roger B. J.|last3=Sampson|first3=Scott D.|date=2012-06-01|title=The phylogeny of Tetanurae (Dinosauria: Theropoda)|journal=Journal of Systematic Palaeontology|volume=10|issue=2|pages=211–300|doi=10.1080/14772019.2011.630927|issn=1477-2019}}</ref> Allosauridae is a fairly old taxonomic group, having been first named by the American paleontologist [[Othniel Charles Marsh]] in 1878.<ref>Marsh, Othniel Charles (1878). "Notice of new dinosaurian reptiles". ''American Journal of Science and Arts''. '''15''': 241–244.</ref> Allosaurids are characterized by an [[Talus bone|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.<ref name=":1">{{Cite journal|last=Molnar|first=R. E.|last2=Flannery|first2=Timothy F.|last3=Rich|first3=Thomas H. V.|date=1981-01-01|title=An allosaurid theropod dinosaur from the Early Cretaceous of Victoria, Australia|journal=Alcheringa: An Australasian Journal of Palaeontology|volume=5|issue=2|pages=141–146|doi=10.1080/03115518108565427|issn=0311-5518}}</ref>


== Description ==
== Description ==
Allosaurids have a general anatomy typical of other [[Neotheropoda|neotheropod]] dinosaurs, contributing to the difficulty in defining the family's membership. A typical 8m specimen of ''Allosaurus fragilis'' had a skull of about 0.85m. The [[premaxilla]] has five teeth and the [[maxilla]] usually around 16. The dentary also typically has 16 teeth. All teeth are serrated and continuously replaced throughout the life of the animal. Allosaurid skulls are characterized by two sets of crests formed by the nasal and lacrimal bones respectively. These crests would have been covered by keratin sheathes.<ref name=":8">Madsen, James H., Jr. (1993) [1976]. ''Allosaurus fragilis: A Revised Osteology''. Utah Geological Survey Bulletin '''109''' (2nd ed.). Salt Lake City: Utah Geological Survey.</ref> The skull also exhibits features consistent with significant cranial kinesis: a synovial joint between the braincase and the frontals and a loose articulation between the dentary and the angular/surangular.<ref name=":9">Paul, Gregory S. (1988). Predatory Dinosaurs of the World.</ref> This [[cranial kinesis]] would have dampened forces on the bones of the skull and allowed allosaurids to open their mouths to very large angles.
Allosaurids have a general anatomy typical of other [[Neotheropoda|neotheropod]] dinosaurs, contributing to the difficulty in defining the family's membership. A typical 8m specimen of ''Allosaurus fragilis'' had a skull of about 0.85m. The [[premaxilla]] has five teeth and the [[maxilla]] usually around 16. The dentary also typically has 16 teeth. All teeth are serrated and continuously replaced throughout the life of the animal. Allosaurid skulls are characterized by two sets of crests formed by the nasal and lacrimal bones respectively. These crests would have been covered by keratin sheathes.<ref name=":8">Madsen, James H., Jr. (1993) [1976]. ''Allosaurus fragilis: A Revised Osteology''. Utah Geological Survey Bulletin '''109''' (2nd ed.). Salt Lake City: Utah Geological Survey.</ref> The skull also exhibits features consistent with significant cranial kinesis: a synovial joint between the braincase and the frontals and a loose articulation between the dentary and the angular/surangular.<ref name=":9">Paul, Gregory S. (1988). Predatory Dinosaurs of the World.</ref> This [[cranial kinesis]] would have dampened forces on the bones of the skull and allowed allosaurids to open their mouths to very large angles.


Allosaurids have 28 precaudal [[vertebrae]] (9 cervical, 14 dorsal, 5 sacral) and an estimated 45–50 caudal vertebrae.<ref name=":9" /> Gastralia and ferculae are rarely preserved as fossils but are presumed to occur in all allosaurids<ref>Chure, Daniel J.; Madsen, James (1996). "On the presence of furculae in some non-maniraptoran theropods". ''Journal of Vertebrate Paleontology''. '''16''' (3): 573–577. [[Digital object identifier|doi]]:[https://doi.org/10.1080%2F02724634.1996.10011341 10.1080/02724634.1996.10011341]</ref> The pubis is highly elongated and extends ventrally to form a pubic foot which like in other large dinosaurs is thought to have been used to support the weight of the body in a resting crouch position.<ref name=":8" />
Allosaurids have 28 precaudal [[vertebrae]] (9 cervical, 14 dorsal, 5 sacral) and an estimated 45–50 caudal vertebrae.<ref name=":9" /> Gastralia and furculae are rarely preserved as fossils but are presumed to occur in all allosaurids.<ref>Chure, Daniel J.; Madsen, James (1996). "On the presence of furculae in some non-maniraptoran theropods". ''Journal of Vertebrate Paleontology''. '''16''' (3): 573–577. [[Digital object identifier|doi]]:[https://doi.org/10.1080%2F02724634.1996.10011341 10.1080/02724634.1996.10011341]</ref> The pubis is highly elongated and extends ventrally to form a pubic foot which like in other large dinosaurs is thought to have been used to support the weight of the body in a resting crouch position.<ref name=":8" />


Like most other [[theropods]], allosaurids have very short forelimbs relative to their hindlimbs with three digits on the hand and four on the foot. The first digit of the hand forms a semi-opposable thumb and digits 4 and 5 are absent. Digits 2–4 of the foot are robust but digit 1 is reduced and does not touch the ground and digit 5 is absent.<ref name=":10">Gilmore, Charles W. (1920). Osteology of the Carnivorous Dinosauria in the United States National Museum: With Special Reference to the Genera Antrodemus (Allosaurus) and Ceratosaurus. United States National Museum Bulletin Volume 110.</ref> All distal phalanges were capped with large claws, those on the hand were especially long and were curved to facilitate raking and grasping of prey items <ref name=":8" /> Phalangeal formulae of the hand and foot are 4-3-4 and 2-3-4-5 respectively.<ref name=":10" />
Like most other [[theropods]], allosaurids have very short forelimbs relative to their hindlimbs with three digits on the hand and four on the foot. The first digit of the hand forms a semi-opposable thumb and digits 4 and 5 are absent. Digits 2–4 of the foot are robust but digit 1 is reduced and does not touch the ground and digit 5 is absent.<ref name=":10">Gilmore, Charles W. (1920). Osteology of the Carnivorous Dinosauria in the United States National Museum: With Special Reference to the Genera Antrodemus (Allosaurus) and Ceratosaurus. United States National Museum Bulletin Volume 110.</ref> All distal phalanges were capped with large claws, those on the hand were especially long and were curved to facilitate raking and grasping of prey items.<ref name=":8" /> Phalangeal formulae of the hand and foot are 4-3-4 and 2-3-4-5 respectively.<ref name=":10" />


==Classification==
==Classification==
In 2019, Rauhut and Pol described ''[[Asfaltovenator|Asfaltovenator vialidadi]]'', a basal allosauroid displaying a mosaic of primitive and derived features seen within [[Tetanurae]]. Their phylogenetic analysis found traditional [[Megalosauroidea]] to represent a basal [[evolutionary grade|grade]] of [[Carnosauria|carnosaurs]], [[paraphyly|paraphyletic]] with respect to [[Allosauroidea]].<ref name="Rauhut2019">{{Cite journal|last=Rauhut|first=Oliver W. M.|last2=Pol|first2=Diego|date=2019-12-11|title=Probable basal allosauroid from the early Middle Jurassic Cañadón Asfalto Formation of Argentina highlights phylogenetic uncertainty in tetanuran theropod dinosaurs|journal=Scientific Reports|language=en|volume=9|issue=1|pages=18826|doi=10.1038/s41598-019-53672-7|pmid=31827108|pmc=6906444|issn=2045-2322}}</ref>
In 2019, Rauhut and Pol described ''[[Asfaltovenator|Asfaltovenator vialidadi]]'', a basal allosauroid displaying a mosaic of primitive and derived features seen within [[Tetanurae]]. Their phylogenetic analysis found traditional [[Megalosauroidea]] to represent a basal [[evolutionary grade|grade]] of [[Carnosauria|carnosaurs]], [[paraphyly|paraphyletic]] with respect to [[Allosauroidea]]. They also noted that the definitive taxonomic placement of ''Saurophaganax'' within [[Allosauroidea]] is unstable, being recovered as a sister taxon of [[Metriacanthosauridae]] or Allosauria, or even as a basalmost carcharodontosaurian.<ref name="Rauhut2019">{{Cite journal|last=Rauhut|first=Oliver W. M.|last2=Pol|first2=Diego|date=2019-12-11|title=Probable basal allosauroid from the early Middle Jurassic Cañadón Asfalto Formation of Argentina highlights phylogenetic uncertainty in tetanuran theropod dinosaurs|journal=Scientific Reports|language=en|volume=9|issue=1|pages=18826|doi=10.1038/s41598-019-53672-7|pmid=31827108|pmc=6906444|issn=2045-2322}} [https://www.nature.com/articles/s41598-019-53672-7#MOESM1 Supplementary information]</ref>


{{clade| style=font-size:100%;line-height:80%
{{clade| style=font-size:100%;line-height:80%
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|1=[[Neovenatoridae]][[File:Neovenator.png|120px]]
|1=[[Neovenatoridae]][[File:Neovenator.png|120px]]
|2=[[Carcharodontosauridae]][[File:Carcharodontosaurus.png|120px]]}} }} }} }} }} }} }} }} }}
|2=[[Carcharodontosauridae]][[File:Carcharodontosaurus.png|120px]]}} }} }} }} }} }} }} }} }}

In 2024, ''[[Saurophaganax]]'' was recovered as a sister taxon of the [[Metriacanthosauridae|metriacanthosaurid]] ''[[Yangchuanosaurus|Yangchuanosaurus shangyouensis]]'', indicating that the genus might be a [[Metriacanthosauridae|metriacanthosaurid]] instead of an allosaurid.<ref>{{Cite journal|last=Cau |first=A. |title=A Unified Framework for Predatory Dinosaur Macroevolution |year=2024 |journal=Bollettino della Società Paleontologica Italiana |volume=63 |issue=1 |doi=10.4435/BSPI.2024.08 |url=https://www.researchgate.net/publication/379902868_A_Unified_Framework_for_Predatory_Dinosaur_Macroevolution }} [https://www.paleoitalia.it/bollettino-spi/bspi-vol-631/ Supplementary Material]</ref>


==References==
==References==
⚫
{{Wikispecies}}
{{Reflist}}
{{Reflist}}


==External links==
{{Commons category}}
⚫
{{Wikispecies}}
{{Theropoda|A.}}
{{Theropoda|A.}}
{{Portal bar|Dinosaurs|Paleontology}}
{{Portal bar|Dinosaurs|Paleontology}}
{{Taxonbar|from=Q131684}}
{{Taxonbar|from=Q131684}}


[[Category:Allosaurids| ]]
[[Category:Allosauridae| ]]
[[Category:Carnosaurs]]
[[Category:Kimmeridgian first appearances]]
[[Category:Kimmeridgian first appearances]]
[[Category:Late Jurassic extinctions]]
[[Category:Late Jurassic extinctions]]
[[Category:Taxa named by Othniel Charles Marsh]]
[[Category:Taxa named by Othniel Charles Marsh]]
[[Category:Late Jurassic taxonomic families]]
[[Category:Prehistoric dinosaur families]]
[[Category:Prehistoric dinosaur families]]

Latest revision as of 08:52, 21 October 2024

Allosaurids
Temporal range: Late Jurassic, 155–145 Ma
An A. fragilis skeletal mount, at the Carnegie Museum of Natural History
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Superfamily: †Allosauroidea
Family: †Allosauridae
Marsh, 1878
Type species
†Allosaurus fragilis
Marsh, 1877
Genera[1]
Synonyms
  • Antrodemidae Marsh, 1878
  • Labrosauridae Marsh, 1882

Allosauridae is an extinct family of medium to large bipedal, carnivorous allosauroid theropod dinosaurs from the Late Jurassic.[2] Allosauridae is a fairly old taxonomic group, having been first named by the American paleontologist Othniel Charles Marsh in 1878.[3] 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.[4]

Description

[edit]

Allosaurids have a general anatomy typical of other neotheropod dinosaurs, contributing to the difficulty in defining the family's membership. A typical 8m specimen of Allosaurus fragilis had a skull of about 0.85m. The premaxilla has five teeth and the maxilla usually around 16. The dentary also typically has 16 teeth. All teeth are serrated and continuously replaced throughout the life of the animal. Allosaurid skulls are characterized by two sets of crests formed by the nasal and lacrimal bones respectively. These crests would have been covered by keratin sheathes.[5] The skull also exhibits features consistent with significant cranial kinesis: a synovial joint between the braincase and the frontals and a loose articulation between the dentary and the angular/surangular.[6] This cranial kinesis would have dampened forces on the bones of the skull and allowed allosaurids to open their mouths to very large angles.

Allosaurids have 28 precaudal vertebrae (9 cervical, 14 dorsal, 5 sacral) and an estimated 45–50 caudal vertebrae.[6] Gastralia and furculae are rarely preserved as fossils but are presumed to occur in all allosaurids.[7] The pubis is highly elongated and extends ventrally to form a pubic foot which like in other large dinosaurs is thought to have been used to support the weight of the body in a resting crouch position.[5]

Like most other theropods, allosaurids have very short forelimbs relative to their hindlimbs with three digits on the hand and four on the foot. The first digit of the hand forms a semi-opposable thumb and digits 4 and 5 are absent. Digits 2–4 of the foot are robust but digit 1 is reduced and does not touch the ground and digit 5 is absent.[8] All distal phalanges were capped with large claws, those on the hand were especially long and were curved to facilitate raking and grasping of prey items.[5] Phalangeal formulae of the hand and foot are 4-3-4 and 2-3-4-5 respectively.[8]

Classification

[edit]

In 2019, Rauhut and Pol described Asfaltovenator vialidadi, a basal allosauroid displaying a mosaic of primitive and derived features seen within Tetanurae. Their phylogenetic analysis found traditional Megalosauroidea to represent a basal grade of carnosaurs, paraphyletic with respect to Allosauroidea. They also noted that the definitive taxonomic placement of Saurophaganax within Allosauroidea is unstable, being recovered as a sister taxon of Metriacanthosauridae or Allosauria, or even as a basalmost carcharodontosaurian.[9]

Carnosauria

In 2024, Saurophaganax was recovered as a sister taxon of the metriacanthosaurid Yangchuanosaurus shangyouensis, indicating that the genus might be a metriacanthosaurid instead of an allosaurid.[10]

References

[edit]
  1. ^ Carrano, M. T.; Benson, R. B. J.; Sampson, S. D. (2012). "The phylogeny of Tetanurae (Dinosauria: Theropoda)". Journal of Systematic Palaeontology. 10 (2): 211–300. doi:10.1080/14772019.2011.630927.
  2. ^ Carrano, Matthew T.; Benson, Roger B. J.; Sampson, Scott D. (2012-06-01). "The phylogeny of Tetanurae (Dinosauria: Theropoda)". Journal of Systematic Palaeontology. 10 (2): 211–300. doi:10.1080/14772019.2011.630927. ISSN 1477-2019.
  3. ^ Marsh, Othniel Charles (1878). "Notice of new dinosaurian reptiles". American Journal of Science and Arts. 15: 241–244.
  4. ^ Molnar, R. E.; Flannery, Timothy F.; Rich, Thomas H. V. (1981-01-01). "An allosaurid theropod dinosaur from the Early Cretaceous of Victoria, Australia". Alcheringa: An Australasian Journal of Palaeontology. 5 (2): 141–146. doi:10.1080/03115518108565427. ISSN 0311-5518.
  5. ^ a b c Madsen, James H., Jr. (1993) [1976]. Allosaurus fragilis: A Revised Osteology. Utah Geological Survey Bulletin 109 (2nd ed.). Salt Lake City: Utah Geological Survey.
  6. ^ a b Paul, Gregory S. (1988). Predatory Dinosaurs of the World.
  7. ^ Chure, Daniel J.; Madsen, James (1996). "On the presence of furculae in some non-maniraptoran theropods". Journal of Vertebrate Paleontology. 16 (3): 573–577. doi:10.1080/02724634.1996.10011341
  8. ^ a b Gilmore, Charles W. (1920). Osteology of the Carnivorous Dinosauria in the United States National Museum: With Special Reference to the Genera Antrodemus (Allosaurus) and Ceratosaurus. United States National Museum Bulletin Volume 110.
  9. ^ Rauhut, Oliver W. M.; Pol, Diego (2019-12-11). "Probable basal allosauroid from the early Middle Jurassic Cañadón Asfalto Formation of Argentina highlights phylogenetic uncertainty in tetanuran theropod dinosaurs". Scientific Reports. 9 (1): 18826. doi:10.1038/s41598-019-53672-7. ISSN 2045-2322. PMC 6906444. PMID 31827108. Supplementary information
  10. ^ Cau, A. (2024). "A Unified Framework for Predatory Dinosaur Macroevolution". Bollettino della Società Paleontologica Italiana. 63 (1). doi:10.4435/BSPI.2024.08. Supplementary Material
[edit]
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