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{{italictitle}}

{{Taxobox
{{Taxobox
| name = ''Ectenosaurus''
| name = ''Ectenosaurus''
| image = Ectenosaurus clidastoides.png
| image = Ectenosaurus clidastoides skeleton.png
| image_upright = 1.2
| image_upright = 1.2
| image_caption = Partial skeleton (A) and soft tissues (B) of ''Ectenosaurus clidastoides''.
| image_caption = Partial skeleton of ''Ectenosaurus clidastoides''.
| regnum = [[Animal]]ia
| regnum = [[Animal]]ia
| phylum = [[Chordata]]
| phylum = [[Chordata]]
Line 12: Line 14:
| genus_authority = Russell, 1967
| genus_authority = Russell, 1967
| fossil_range = [[Late Cretaceous]], [[Santonian]]
| fossil_range = [[Late Cretaceous]], [[Santonian]]
{{Fossilrange|86|83}}
{{Fossilrange|85.8|84.9}}
| superfamilia = †[[Mosasauroidea]]
| superfamilia = †[[Mosasauroidea]]
| subfamilia = †[[Mosasaurinae]]
| subfamilia = †[[Mosasaurinae]]
| synonyms = * ''[[Platecarpus]] clidastoides'' <small>Merriam, 1894</small>
| subdivision_ranks = Species
| subdivision_ranks = Species
| subdivision = * ''E. clidastoides'' <small>Merriam, 1894([[type]])</small>
| subdivision = * ''E. clidastoides'' <small>Merriam, 1894([[type]])</small>
}}
}}


'''''Ectenosaurus''''' is an extinct [[genus]] of marine lizard belonging to the [[mosasaur]] family. Though traditionally classified as part of the [[Plioplatecarpinae]] subfamily, recent analyses recover it as part of the [[Mosasaurinae]] alongside genera like ''[[Prognathodon]]'' and ''[[Mosasaurus]]''. ''Ectenosaurus'' is exclusively known from the [[Santonian]] of [[Kansas]] and [[Texas]].
⚫
'''''Ectenosaurus''''' is a [[genus]] of [[mosasaur]] from the [[Late Cretaceous]] period of [[Kansas]] and [[Texas]]. It is a [[Mosasaurinae|Mosasaurine]]<ref>{{Cite journal|last=Simões|first=Tiago R.|last2=Vernygora|first2=Oksana|last3=Paparella|first3=Ilaria|last4=Jimenez-Huidobro|first4=Paulina|last5=Caldwell|first5=Michael W.|date=2017-05-03|title=Mosasauroid phylogeny under multiple phylogenetic methods provides new insights on the evolution of aquatic adaptations in the group|url=http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0176773|journal=PLOS ONE|volume=12|issue=5|pages=e0176773|doi=10.1371/journal.pone.0176773|issn=1932-6203}}</ref> about 5 meters long.


The generic name means "Drawn-out lizard", from [[Greek language|Greek]] ''ectenes'' ("drawn-out") and Greek ''sauros'' ("lizard") referencing the elongated muzzle.
⚫
== References ==
<references />


==See also==
== Description ==
[[File:Ectenosaurus clidastoides.png|left|thumb|Partial skeleton (A) and soft tissues (B) of ''Ectenosaurus clidastoides''.]]
⚫
{{portal|Paleontology}}
Based on the size of the preserved skull, about 74 centimeters in length, ''Ectenosaurus'' would have reached sizes of 5,7 meters in length. It was a rare genus of [[mosasaur]] with several unique characteristics that clearly separate it from other mosasaur genera. The most prominent of these features is its elongated jaws, elongated in a similar vein to other mosasaurs with elongated jaws, such as ''[[Plotosaurus]]'' and ''[[Pluridens]]''.
* [[List of mosasaurs]]


Russell (1967) considered the form of the teeth, the shape of the frontal and the large suprastapedial process of the quadrate as evidence of a close relation between ''Ectenosaurus'' and ''[[Platecarpus]]''. Such a relation is not supported in most recent phylogenetic analyses. He separated ''Ectenosaurus'' from ''Platecarpus'' based on the elongated snout, the exclusion of the prefrontals from the narial borders and the fusion of the supra- and infrastepedial processes.<ref name=":1">{{Cite journal|last=Russell|first=Dale. A.|date=6 November 1967|title=Systematics and Morphology of American Mosasaurs|url=http://peabody.yale.edu/sites/default/files/documents/scientific-publications/ypmB23_1967.pdf|journal=Bulletin of the Peabody Museum of Natural History (Yale University)|volume=|pages=|via=}}</ref>
==External links==
* [http://www.oceansofkansas.com/ Oceans of Kansas]


=== Scales and locomotion ===
⚫
{{Mosasauridae}}
The specimen FHSM VP-401 preserve significantly comprehensive skin impressions from ''Ectenosaurus'', which makes it possible to draw conclusions not only about mosasaur integument at large but also about mosasaur movement and propulsion. The scales are considerably smaller in size (2.7×2.0 mm) than those found in the famed LACM 128319 specimen of ''[[Platecarpus]]'' (3.8×4.4 mm), despite the animals being of similar sizes.<ref name=":0">{{Cite journal|last=Lindgren|first=Johan|last2=Everhart|first2=Michael J.|last3=Caldwell|first3=Michael W.|date=2011-11-16|title=Three-Dimensionally Preserved Integument Reveals Hydrodynamic Adaptations in the Extinct Marine Lizard Ectenosaurus (Reptilia, Mosasauridae)|url=http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0027343|journal=PLOS ONE|volume=6|issue=11|pages=e27343|doi=10.1371/journal.pone.0027343|issn=1932-6203}}</ref>


The combination of small and firmly anchored body scales as well as a complex meshwork of alternating crossed-helical and longitudinal fiber bundles suggest that the anterior torso of ''Ectenosaurus'' was reasonably stiff. This also suggests that this section of the body was quite rigid during locomation, and that the main form of propulsion would have to have been done by the tail (likely possessing a tail fin like other mosasaur species), and that it could not move by undulating its entire body like [[Snake|snakes]] do, a previously popular view of mosasaur locomotion.<ref name=":0" />

== History of discovery ==
''Ectenosaurus'' was originally described as a species of ''[[Platecarpus]]'', ''P. clidastoides'', in 1894. The type specimen was collected by C.H. Sternberg or G. Bauer from [[Logan County, Kansas|Logan County]] in [[Kansas]] and was housed in the Bayerische Staatssammlung fur Palaontologie in Munich, where it was likely destroyed during the [[World War II|Second World War]]. Fortunately, a second specimen (which was also much better preserved) was discovered by George Sternberg in 1953, which he initially identified as a ''[[Clidastes|Clidastes velox]]''. The specimen, GFS 109-53, was about 3 meters in length and largely articulated, though the tail and rear limbs were missing due to erosion.<ref name=":2">{{Cite web|url=http://oceansofkansas.com/ectenosaurus.html|title=Ectenosaurus|website=oceansofkansas.com|access-date=2017-09-27}}</ref>

This specimen was then exhibited at the [[Sternberg Memorial Museum]] on the campus of [[Fort Hays State University]] from its discovery until 1999 when the museum was closed and moved. Since the museum moved, the specimen remains in storage.<ref name=":2" /> It was examined in 1963 by [[Dale Russell|Dale A. Russell]] who determined that it represented a ''Platecarpus clidastoides'' and not a ''Clidastes velox''. In his ''Sytematics and Morphology of American Mosasaurs'' (1967) he re-described the species as part of a new genus, ''Ectenosaurus''.<ref name=":1" />

== Classification ==
⚫
''Ectenosaurus'' has been seen as a [[Plioplatecarpinae|plioplatecarpine]] for most of the time since its discovery, partly due to long having been classified as a species of ''[[Platecarpus]]''. Recent analyses recover it as a [[Mosasaurinae|mosasaurine]] however, sharing close relations with ''[[Prognathodon]]''.<ref>{{Cite journal|last=Simões|first=Tiago R.|last2=Vernygora|first2=Oksana|last3=Paparella|first3=Ilaria|last4=Jimenez-Huidobro|first4=Paulina|last5=Caldwell|first5=Michael W.|date=2017-05-03|title=Mosasauroid phylogeny under multiple phylogenetic methods provides new insights on the evolution of aquatic adaptations in the group|url=http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0176773|journal=PLOS ONE|volume=12|issue=5|pages=e0176773|doi=10.1371/journal.pone.0176773|issn=1932-6203}}</ref>

The cladogram below follows a comprehensive 2010 analysis of the [[Anguimorpha]] based on morphology-only characters, collapsed to only display the [[Mosasaur|Mosasauridae]].<ref name="C10">{{cite journal|last=Conrad|first=J.L.|last2=Ast|first2=J.C.|last3=Montanari|first3=S.|last4=Norell|first4=M.A.|year=2010|title=A combined evidence phylogenetic analysis of Anguimorpha (Reptilia: Squamata)|url=http://www.academia.edu/386721/A_Combined_Evidence_Phylogenetic_Analysis_of_Anguimorpha_Reptilia_Squamata_|journal=Cladistics|volume=27|issue=3|doi=10.1111/j.1096-0031.2010.00330.x|issn=0748-3007}}</ref> The placements of [[Prognathodontini]] and [[Mosasaurini]] follow Russell (1967).<ref name=":1" />{{clade|{{clade
|label1=[[Halisaurinae]]
|1={{clade
|1=''[[Eonatator sternbergii]]''
|2=''[[Halisaurus arambourgi]]''
|3=''[[Halisaurus platyspondylus]]'' }}
|2={{clade
|label1=[[Russellosaurina]]
|1={{clade
|1=''[[Plioplatecarpus primaevus]]''
|2={{clade
|1=''[[Platecarpus tympaniticus]]''
|label2=[[Tylosaurinae]]
|2={{clade
|1={{clade
|1=''[[Lakumasaurus antarcticus]]''
|2=''[[Taniwhasaurus oweni]]'' }}
|2=''[[Tylosaurus proriger]]''
|3={{clade
|1=''[[Tylosaurus nepaeolicus]]''
|2=''[[Hainosaurus bernardi]]'' }} }} }} }}
|label2=[[Mosasaurinae]]
|2={{clade
|label1=[[Prognathodontini]]
|1={{clade
|1={{clade
|1='''''Ectenosaurus clidastoides'''''
|2=''[[Goronyosaurus|Goronyosaurus nigeriensis]]'' }}
|2={{clade
|1=''[[Plesiotylosaurus crassidens]]''
|2={{clade
|1=''[[Prognathodon solvayi]]''
|2=''[[Prognathodon overtoni]]'' }} }} }}
|label2=[[Mosasaurini]]
|2={{clade
|1=''[[Clidastes liodontus]]''
|2={{clade
|1=''[[Globidens alabamaensis]]''
|2={{clade
|1=''[[Mosasaurus hoffmanni]]''
|2={{clade
|1=''[[Mosasaurus lemonnieri]]''
|2={{clade
|1=''[[Moanasaurus mangahouangae]]''
|2={{clade
|1=''[[Plotosaurus bennisoni]]''
|2=''[[Plotosaurus tuckeri]]'' }} }} }} }} }} }} }} }} }}|style=font-size:85%; line-height:85%|label1=[[Mosasauridae]]}}

⚫
== References ==
⚫
<references />{{portal|Paleontology}}
[[Category:Russellosaurins]]
[[Category:Russellosaurins]]
[[Category:Extinct reptiles of New Zealand]]
[[Category:Extinct reptiles of New Zealand]]
Line 39: Line 101:
[[Category:Fossil taxa described in 1967]]
[[Category:Fossil taxa described in 1967]]
[[Category:Taxa named by Dale Russell]]
[[Category:Taxa named by Dale Russell]]
⚫
{{Mosasauridae}}

{{paleo-lizard-stub}}

Revision as of 15:49, 27 September 2017


Ectenosaurus
Temporal range: Late Cretaceous, Santonian 85.8–84.9 Ma
↓
Partial skeleton of Ectenosaurus clidastoides.
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Reptilia
Order:
Squamata
Superfamily:
†Mosasauroidea
Family:
†Mosasauridae
Subfamily:
†Mosasaurinae
Genus:
†Ectenosaurus

Russell, 1967
Species
  • E. clidastoides Merriam, 1894(type)
Synonyms

Ectenosaurus is an extinct genus of marine lizard belonging to the mosasaur family. Though traditionally classified as part of the Plioplatecarpinae subfamily, recent analyses recover it as part of the Mosasaurinae alongside genera like Prognathodon and Mosasaurus. Ectenosaurus is exclusively known from the Santonian of Kansas and Texas.

The generic name means "Drawn-out lizard", from Greek ectenes ("drawn-out") and Greek sauros ("lizard") referencing the elongated muzzle.

Description

Partial skeleton (A) and soft tissues (B) of Ectenosaurus clidastoides.

Based on the size of the preserved skull, about 74 centimeters in length, Ectenosaurus would have reached sizes of 5,7 meters in length. It was a rare genus of mosasaur with several unique characteristics that clearly separate it from other mosasaur genera. The most prominent of these features is its elongated jaws, elongated in a similar vein to other mosasaurs with elongated jaws, such as Plotosaurus and Pluridens.

Russell (1967) considered the form of the teeth, the shape of the frontal and the large suprastapedial process of the quadrate as evidence of a close relation between Ectenosaurus and Platecarpus. Such a relation is not supported in most recent phylogenetic analyses. He separated Ectenosaurus from Platecarpus based on the elongated snout, the exclusion of the prefrontals from the narial borders and the fusion of the supra- and infrastepedial processes.[1]

Scales and locomotion

The specimen FHSM VP-401 preserve significantly comprehensive skin impressions from Ectenosaurus, which makes it possible to draw conclusions not only about mosasaur integument at large but also about mosasaur movement and propulsion. The scales are considerably smaller in size (2.7×2.0 mm) than those found in the famed LACM 128319 specimen of Platecarpus (3.8×4.4 mm), despite the animals being of similar sizes.[2]

The combination of small and firmly anchored body scales as well as a complex meshwork of alternating crossed-helical and longitudinal fiber bundles suggest that the anterior torso of Ectenosaurus was reasonably stiff. This also suggests that this section of the body was quite rigid during locomation, and that the main form of propulsion would have to have been done by the tail (likely possessing a tail fin like other mosasaur species), and that it could not move by undulating its entire body like snakes do, a previously popular view of mosasaur locomotion.[2]

History of discovery

Ectenosaurus was originally described as a species of Platecarpus, P. clidastoides, in 1894. The type specimen was collected by C.H. Sternberg or G. Bauer from Logan County in Kansas and was housed in the Bayerische Staatssammlung fur Palaontologie in Munich, where it was likely destroyed during the Second World War. Fortunately, a second specimen (which was also much better preserved) was discovered by George Sternberg in 1953, which he initially identified as a Clidastes velox. The specimen, GFS 109-53, was about 3 meters in length and largely articulated, though the tail and rear limbs were missing due to erosion.[3]

This specimen was then exhibited at the Sternberg Memorial Museum on the campus of Fort Hays State University from its discovery until 1999 when the museum was closed and moved. Since the museum moved, the specimen remains in storage.[3] It was examined in 1963 by Dale A. Russell who determined that it represented a Platecarpus clidastoides and not a Clidastes velox. In his Sytematics and Morphology of American Mosasaurs (1967) he re-described the species as part of a new genus, Ectenosaurus.[1]

Classification

Ectenosaurus has been seen as a plioplatecarpine for most of the time since its discovery, partly due to long having been classified as a species of Platecarpus. Recent analyses recover it as a mosasaurine however, sharing close relations with Prognathodon.[4]

The cladogram below follows a comprehensive 2010 analysis of the Anguimorpha based on morphology-only characters, collapsed to only display the Mosasauridae.[5] The placements of Prognathodontini and Mosasaurini follow Russell (1967).[1]

Mosasauridae

References

  1. ^ a b c Russell, Dale. A. (6 November 1967). "Systematics and Morphology of American Mosasaurs" (PDF). Bulletin of the Peabody Museum of Natural History (Yale University).
  2. ^ a b Lindgren, Johan; Everhart, Michael J.; Caldwell, Michael W. (2011-11-16). "Three-Dimensionally Preserved Integument Reveals Hydrodynamic Adaptations in the Extinct Marine Lizard Ectenosaurus (Reptilia, Mosasauridae)". PLOS ONE. 6 (11): e27343. doi:10.1371/journal.pone.0027343. ISSN 1932-6203.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  3. ^ a b "Ectenosaurus". oceansofkansas.com. Retrieved 2017-09-27.
  4. ^ Simões, Tiago R.; Vernygora, Oksana; Paparella, Ilaria; Jimenez-Huidobro, Paulina; Caldwell, Michael W. (2017-05-03). "Mosasauroid phylogeny under multiple phylogenetic methods provides new insights on the evolution of aquatic adaptations in the group". PLOS ONE. 12 (5): e0176773. doi:10.1371/journal.pone.0176773. ISSN 1932-6203.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  5. ^ Conrad, J.L.; Ast, J.C.; Montanari, S.; Norell, M.A. (2010). "A combined evidence phylogenetic analysis of Anguimorpha (Reptilia: Squamata)". Cladistics. 27 (3). doi:10.1111/j.1096-0031.2010.00330.x. ISSN 0748-3007.
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