Stratiotosuchus: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
picture
Expansion, more coming
Line 1: Line 1:
{{Automatic taxobox
{{Automatic taxobox
| fossil_range = [[Late Cretaceous]], {{fossil_range|Turonian|Santonian}}
| fossil_range = [[Late Cretaceous]], {{fossil_range|Campanian|Maastrichtian}}
| image = Stratiotosuchus maxhechti.jpg
| image = Stratiotosuchus maxhechti.jpg
| image_width = 250px
| image_width = 250px
Line 9: Line 9:
}}
}}


'''''Stratiotosuchus''''' is an [[extinct]] [[genus]] of [[Baurusuchidae|baurusuchid]] [[mesoeucrocodylia]]n which existed in the [[Adamantina Formation]], [[Brazil]] during the late [[Cretaceous]] period ([[Turonian]]-[[Santonian]] stage).<ref name="Campos">{{Cite journal|author=Campos, D.A., Suarez, J.M., Riff, D. and Kellner, A.W.A.|year=2001|title=Short note on a new Baurusuchidae (Crocodyliformes, Metasuchia) from the Upper Cretaceous of Brazil|journal=Bol. do Museu Nacional, Geologia|volume=57|pages=7}}</ref><ref name="Pinheiro">{{Cite journal|doi=10.4072/rbp.2008.1.04|author=ANDRÉ EDUARDO PIACENTINI PINHEIRO, REINALDO J. BERTINI, MARCO BRANDALISE DE ANDRADE and RAFAEL GIÓIA MARTINS NETO|year=2008|title=A NEW SPECIMEN OF STRATIOTOSUCHUS MAXHECHTI (BAURUSUCHIDAE,CROCODYLIFORMES) FROM THE ADAMANTINA FORMATION (UPPERCRETACEOUS), SOUTHEASTERN BRAZIL|journal=Revista Brasileira De Paleontologia|volume=11|issue=1|pages=37–50|url=http://www.sbpbrasil.org/revista/edicoes/11_1/pinheiro%20etal.pdf}}</ref> It was first named by Campos, D.A., Suarez, J.M., Riff, D. and Kellner, A.W.A. in 2001 and the type species is ''Stratiotosuchus maxhechti''.<ref name="Campos"/> A [[hypercarnivore|hyperpredator]],<ref name="Pinheiro"/> it and other baurusuchids may have filled niches occupied by [[theropod]] [[dinosaur]]s elsewhere.<ref name=MP08>{{cite journal |last=Martinelli |first=Agustín G. |coauthors=and Pais, Diego F. |year=2008 |title=A new baurusuchid crocodyliform (Archosauria) from the Late Cretaceous of Patagonia (Argentina) |journal=Comptes Rendus Palevol |volume=7 |issue=6 |pages=371–381 |doi=10.1016/j.crpv.2008.05.002}}</ref><ref>{{Cite journal | doi = 10.1016/j.cretres.2006.05.002 | author = Candeiro, C. R. A., Martinelli, A. G., Avilla, L. S. & Rich, T. H. | year = 2006 | title = Tetrapods from the Upper Cretaceous (Turonian-Maastrichtian) Bauru Group of Brazil: a reappraisal | url = | journal = Cretaceous Research | volume = 27 | issue = 6| pages = 923–946 }}</ref>
'''''Stratiotosuchus''''' (from [[Greek language|Greek]], {{polytonic|[[wikt:στρατιώτης|στρατιώτης]]}} (stratiotis, "soldier") and {{polytonic|[[wikt:σοῦχος|σοῦχος]]}} (suchos, "crocodile")) is an [[extinct]] [[genus]] of [[Baurusuchidae|baurusuchid]] [[mesoeucrocodylia]]n from the [[Adamantina Formation]] in [[Brazil]]. It lived during the [[Late Cretaceous]].<ref name=CSRK01>{{cite journal |last=Campos |first=D.A. |coauthors=Suarez, J.M.; Riff, D.; and Kellner, A.W.A. |year=2001 |title= Short note on a new Baurusuchidae (Crocodyliformes, Metasuchia) from the Upper Cretaceous of Brazil |journal=Boletim do Museu Nacional, Nova Série, Geologia |volume=57 |pages=1–7 |url=http://ufu.academia.edu/DouglasRiff/Papers/1308682/Short_note_on_a_new_Baurusuchidae_Crocodyliformes_Metasuchia_from_the_Upper_Cretaceous_of_Brazil}}</ref><ref name="Pinheiro">{{Cite journal|doi=10.4072/rbp.2008.1.04|author=ANDRÉ EDUARDO PIACENTINI PINHEIRO, REINALDO J. BERTINI, MARCO BRANDALISE DE ANDRADE and RAFAEL GIÓIA MARTINS NETO|year=2008|title=A NEW SPECIMEN OF STRATIOTOSUCHUS MAXHECHTI (BAURUSUCHIDAE,CROCODYLIFORMES) FROM THE ADAMANTINA FORMATION (UPPERCRETACEOUS), SOUTHEASTERN BRAZIL|journal=Revista Brasileira De Paleontologia|volume=11|issue=1|pages=37–50|url=http://www.sbpbrasil.org/revista/edicoes/11_1/pinheiro%20etal.pdf}}</ref> The first fossils were found in the 1980s, and the [[type species]] ''Stratiotosuchus maxhechti'' was named in 2001.<ref name=CSRK01/> A [[hypercarnivore|hyperpredator]],<ref name="Pinheiro"/> it and other baurusuchids may have filled niches occupied elsewhere by [[theropod]] [[dinosaur]]s.<ref name=MP08>{{cite journal |last=Martinelli |first=Agustín G. |coauthors=and Pais, Diego F. |year=2008 |title=A new baurusuchid crocodyliform (Archosauria) from the Late Cretaceous of Patagonia (Argentina) |journal=Comptes Rendus Palevol |volume=7 |issue=6 |pages=371–381 |doi=10.1016/j.crpv.2008.05.002}}</ref><ref>{{Cite journal | doi = 10.1016/j.cretres.2006.05.002 | author = Candeiro, C. R. A., Martinelli, A. G., Avilla, L. S. & Rich, T. H. | year = 2006 | title = Tetrapods from the Upper Cretaceous (Turonian-Maastrichtian) Bauru Group of Brazil: a reappraisal | url = | journal = Cretaceous Research | volume = 27 | issue = 6| pages = 923–946 }}</ref>


==Material==
==Description==
''Stratiotosuchus'' has a deep, laterally compressed skull {{convert|470|cm|ft}} long. The teeth are [[ziphodont]], meaning that they are laterally compressed, curved, and serrated. Like other baurusuchids, ''Stratiotosuchus'' has a reduced number of teeth: four in its [[premaxilla]] and five in its [[maxilla]]. When the jaw is closed, the teeth of the upper jaw overlie those of the lower jaw and shear closely together. ''Stratiotosuchus'' has one large caniniform tooth in its premaxilla, and several large maxillary teeth behind it. An enlarged fourth [[dentary bone|dentary]] tooth in the lower jaw also forms a canine, and is visible when the jaw is closed.<ref name=RK11>{{cite journal |last=Riff |first=D. |coauthors=and Kellner, A.W.A. |year=2011 |title=Baurusuchid crocodyliforms as theropod mimics: clues from the skull and appendicular morphology of Stratiotosuchus maxhechti (Upper Cretaceous of Brazil) |journal=Zoological Journal of the Linnean Society |volume=163 |issue=s1 |pages=s37-s56 |doi=10.1111/j.1096-3642.2011.00713.x |url=http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00713.x/full#b15}}</ref>


==History==
Three specimens of ''S. maxhechti'' have been found to date:<ref name="Pinheiro"/>
The first known fossil of ''Stratiotosuchus'' was a nearly complete skeleton, cataloged as DGM 1477-R. It was found by paleontologist José Martin Suárez in the town of [[Irapuru]] in [[São Paulo (state)|São Paulo State]] in 1988. This skeleton and all other specimens of ''Stratiotosuchus'' come from the Adamantina Formation, which is either [[Turonian]]-[[Santonian]] in age (about 85 million years old) or [[Campanian]]-[[Maastrichtian]] in age (about 70 million years old). DGM 1477-R includes a nearly complete skull, partial lower jaw, vertebral column, and limb bones. The skeleton was identified as that of a baurusuchid, closely related but distinct from ''[[Baurusuchus pachechoi]]'', which had been known since 1945. ''Stratiotosuchus maxhechti'' was named in 2001 on the basis of this skeleton, designated the [[holotype]] of the species. ''Stratiotosuchus'' means "soldier crocodile" in Greek, and the species name honors paleontologist Max K. Hetch.<ref name=CSRK01/>


Further preparation of DGM 1477-R revealed that two individuals were present in the same block of sandstone, as indicated by two extra leg bones, an extra fragment of the hip, and extra [[metatarsal]]s. They are the same size as the other bones, suggesting that the second individual was equal in body size to the first.<ref name=RK11/>
*DGM 1477-R (holotype)

*MCT 1714-R
==Classification==
*URC R•73
''Stratiotosuchus'' has been recognized as a baurusuchid since it was first described in 1988.<ref name=CS88>{{cite journal |last=Campos |first=D.A.|coauthors=and Suarez, J.M. |year=1988 |title=Um novo Baurusuchidae (Reptilia, Crocodylia) do Cretáceo Superior do Estado de São Paulo |journal=Anais da Academia Brasileira de Ciências |volume=27 |pages=412}}</ref> In 2004, Baurusuchidae was even defined as the [[most recent common ancestor]] of ''Baurusuchus'' and ''Stratiotosuchus'' and all of its descendants; thus, the definition of Baurusuchidae relies on the inclusion of ''Stratiotosuchus''.<ref name=Cetal04>{{cite journal |last=Carvalho |first=I.S. |coauthors=Ribeiro, L.C.B.; and Avilla, L.S. |year=2004 |title=''Uberabasuchus terrificus sp. nov.'', a new Crocodylomorpha from the Bauru Basin (Upper Cretaceous), Brazil |journal=Gondwana Research |volume=7 |issue=4 |pages=975–1002 |issn=1342-937X |url=http://acd.ufrj.br/ismar/3/3_15.pdf |doi=10.1016/S1342-937X(05)71079-0}}</ref> ''Stratiotosuchus'' and ''Baurusuchus'' both belong to a large [[clade]] called [[Metasuchia]], which includes living crocodilians and many extinct relatives extending back into the Jurassic. However, the exact position of ''Stratiotosuchus'' and ''Baurusuchus'' within Metasuchia is still uncertain. Below are several possibilities that have been uncovered in various [[phylogenetic]] analyses:
* Baurusuchidae is grouped with the family [[Sebecidae]] in a clade called [[Sebecosuchia]].
* Sebecids are closer to [[Neosuchia]] (the group including modern crocodilians), while baurusuchids are either [[basal (phylogenetics)|basal]] metasuchians or deeply nested within [[Notosuchia]], a large clade of extinct metasuchians.
* Baurusuchidae is [[polyphyletic]], with ''Stratiotosuchus'' and ''Baurusuchus'' positioned as basal metasuchians while other baurusuchids are placed in the clade [[Sebecia]] along with sebecids.<ref name=RK11/>

Montefeltro ''et al.'' (2011) found support for baurusuchids as advanced notosuchians, and divided the family into two subfamilies, [[Baurusuchinae]] and [[Pissarrachampsinae]]. ''Stratiotosuchus'' belonged to Baurusuchinae along with ''Baurusuchus''. Below is the [[cladogram]] from Montefeltro ''et al.'' (2011):<ref name=MLL11>{{cite journal |last=Montefeltro |first=F.C. |coauthors=Larsson, H.C.E.; and Langer, M.C. |year=2011 |title=A new baurusuchid (Crocodyliformes, Mesoeucrocodylia) from the Late Cretaceous of Brazil and the phylogeny of Baurusuchidae|journal=PLoS ONE |volume=6 |issue=7 |pages= e21916 |doi=10.1371/journal.pone.0021916 |url=http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0021916;jsessionid=23C2B3A83DE943660BF3F97B9E12CB27.ambra01}}</ref>

{{clade| style=font-size:85%;line-height:80%
|label1=[[Notosuchia]]&nbsp;
|1={{clade
|1=''[[Notosuchus]]''
|2={{clade
|1=''[[Mariliasuchus]]''
|2={{clade
|1=''[[Armadillosuchus]]''
|label2=&nbsp;[[Baurusuchia]]/[[Baurusuchidae]]&nbsp;
|2={{clade
|1=''[[Cynodontosuchus]]''
|2={{clade
|label1=&nbsp;[[Pissarrachampsinae]]&nbsp;
|1={{clade
|1=''[[Pissarrachampsa]]''
|2=''[[Wargosuchus]]''}}
|label2=&nbsp;[[Baurusuchinae]]&nbsp;
|2={{clade
|1='''''Stratiotosuchus'''''
|label2=''[[Baurusuchus]]''
|2={{clade
|1=''[[Baurusuchus|B. albertoi]]''
|2={{clade
|1=''[[Baurusuchus|B. salgadoensis]]''
|2=''[[Baurusuchus|B. pachecoi]]''
}} }} }} }} }} }} }} }} }}

Another phylogenetic analysis of baurusuchids was conduced by Riff and Kellner (2011). Their analysis placed ''Stratiotosuchus'' and ''Baurusuchus'' deep within Notosuchia, as the [[sister taxon]] of the family [[Sphagesauridae]]. Below is the cladogram from that study:<ref name=RK11/>

{{clade| style=font-size:85%;line-height:80%
|label1=[[Metasuchia]]&nbsp;
|1={{clade
|1={{clade
|1=''[[Araripesuchus]]''
|label2=[[Notosuchia]]
|2={{clade
|1={{clade
|1=''[[Uruguaysuchus]]''
|2=''[[Candidodon]]''}}
|2={{clade
|1=''[[Libycosuchus]]''
|2={{clade
|1=''[[Simosuchus]]''
|2={{clade
|1={{clade
|1=''[[Chimaerasuchus]]''
|2=''[[Malawisuchus]]''}}
|2={{clade
|1=''[[Notosuchus]]''
|2={{clade
|1=''[[Mariliasuchus]]''
|2={{clade
|1=''[[Comahuesuchus]]''
|2={{clade
|label1=[[Sphagesauridae]]
|1={{clade
|1=''[[Adamantinasuchus]]''
|2={{clade
|1=''[[Armadillosuchus]]''
|2=''[[Sphagesaurus]]''}} }}
|label2=[[Baurusuchidae]]
|2={{clade
|1='''''Stratiotosuchus'''''
|2=''[[Baurusuchus]]''}} }} }} }} }} }} }} }} }} }}
|2={{clade
|1=''[[Lomasuchus]]''
|2={{clade
|1={{clade
|1=''[[Stolokrosuchus]]''
|2={{clade
|label1=[[Sebecidae]]
|1={{clade
|1=''[[Bretesuchus]]''
|2=''[[Sebecus]]''}}
|2={{clade
|1=''[[Uberabasuchus]]''
|2=''[[Hamadasuchus]]''}} }} }}
|2=[[Neosuchia]]
}} }} }} }}

==Paleobiology==
Based on the types of deposits in the Adamantina Formation, ''Stratiotosuchus'' most likely lived alongside a river system with many small [[ephemeral lake]]s.<ref name=RK11/>


==References==
==References==

Revision as of 02:03, 25 February 2012

Stratiotosuchus
Temporal range: Late Cretaceous, Campanian–Maastrichtian
Life restoration of Stratiotosuchus maxhechti
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Clade: †Notosuchia
Clade: †Sebecosuchia
Family: †Baurusuchidae
Subfamily: †Baurusuchinae
Genus: †Stratiotosuchus
Campos et al., 2001
Type species
†S. maxhechti
Campos et al., 2001

Stratiotosuchus (from Greek, στρατιώτης (stratiotis, "soldier") and σοῦχος (suchos, "crocodile")) is an extinct genus of baurusuchid mesoeucrocodylian from the Adamantina Formation in Brazil. It lived during the Late Cretaceous.[1][2] The first fossils were found in the 1980s, and the type species Stratiotosuchus maxhechti was named in 2001.[1] A hyperpredator,[2] it and other baurusuchids may have filled niches occupied elsewhere by theropod dinosaurs.[3][4]

Description

Stratiotosuchus has a deep, laterally compressed skull 470 centimetres (15.4 ft) long. The teeth are ziphodont, meaning that they are laterally compressed, curved, and serrated. Like other baurusuchids, Stratiotosuchus has a reduced number of teeth: four in its premaxilla and five in its maxilla. When the jaw is closed, the teeth of the upper jaw overlie those of the lower jaw and shear closely together. Stratiotosuchus has one large caniniform tooth in its premaxilla, and several large maxillary teeth behind it. An enlarged fourth dentary tooth in the lower jaw also forms a canine, and is visible when the jaw is closed.[5]

History

The first known fossil of Stratiotosuchus was a nearly complete skeleton, cataloged as DGM 1477-R. It was found by paleontologist José Martin Suárez in the town of Irapuru in São Paulo State in 1988. This skeleton and all other specimens of Stratiotosuchus come from the Adamantina Formation, which is either Turonian-Santonian in age (about 85 million years old) or Campanian-Maastrichtian in age (about 70 million years old). DGM 1477-R includes a nearly complete skull, partial lower jaw, vertebral column, and limb bones. The skeleton was identified as that of a baurusuchid, closely related but distinct from Baurusuchus pachechoi, which had been known since 1945. Stratiotosuchus maxhechti was named in 2001 on the basis of this skeleton, designated the holotype of the species. Stratiotosuchus means "soldier crocodile" in Greek, and the species name honors paleontologist Max K. Hetch.[1]

Further preparation of DGM 1477-R revealed that two individuals were present in the same block of sandstone, as indicated by two extra leg bones, an extra fragment of the hip, and extra metatarsals. They are the same size as the other bones, suggesting that the second individual was equal in body size to the first.[5]

Classification

Stratiotosuchus has been recognized as a baurusuchid since it was first described in 1988.[6] In 2004, Baurusuchidae was even defined as the most recent common ancestor of Baurusuchus and Stratiotosuchus and all of its descendants; thus, the definition of Baurusuchidae relies on the inclusion of Stratiotosuchus.[7] Stratiotosuchus and Baurusuchus both belong to a large clade called Metasuchia, which includes living crocodilians and many extinct relatives extending back into the Jurassic. However, the exact position of Stratiotosuchus and Baurusuchus within Metasuchia is still uncertain. Below are several possibilities that have been uncovered in various phylogenetic analyses:

  • Baurusuchidae is grouped with the family Sebecidae in a clade called Sebecosuchia.
  • Sebecids are closer to Neosuchia (the group including modern crocodilians), while baurusuchids are either basal metasuchians or deeply nested within Notosuchia, a large clade of extinct metasuchians.
  • Baurusuchidae is polyphyletic, with Stratiotosuchus and Baurusuchus positioned as basal metasuchians while other baurusuchids are placed in the clade Sebecia along with sebecids.[5]

Montefeltro et al. (2011) found support for baurusuchids as advanced notosuchians, and divided the family into two subfamilies, Baurusuchinae and Pissarrachampsinae. Stratiotosuchus belonged to Baurusuchinae along with Baurusuchus. Below is the cladogram from Montefeltro et al. (2011):[8]

Notosuchia 

Another phylogenetic analysis of baurusuchids was conduced by Riff and Kellner (2011). Their analysis placed Stratiotosuchus and Baurusuchus deep within Notosuchia, as the sister taxon of the family Sphagesauridae. Below is the cladogram from that study:[5]

Metasuchia 

Paleobiology

Based on the types of deposits in the Adamantina Formation, Stratiotosuchus most likely lived alongside a river system with many small ephemeral lakes.[5]

References

  1. ^ a b c Campos, D.A. (2001). "Short note on a new Baurusuchidae (Crocodyliformes, Metasuchia) from the Upper Cretaceous of Brazil". Boletim do Museu Nacional, Nova Série, Geologia. 57: 1–7. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  2. ^ a b ANDRÉ EDUARDO PIACENTINI PINHEIRO, REINALDO J. BERTINI, MARCO BRANDALISE DE ANDRADE and RAFAEL GIÓIA MARTINS NETO (2008). "A NEW SPECIMEN OF STRATIOTOSUCHUS MAXHECHTI (BAURUSUCHIDAE,CROCODYLIFORMES) FROM THE ADAMANTINA FORMATION (UPPERCRETACEOUS), SOUTHEASTERN BRAZIL" (PDF). Revista Brasileira De Paleontologia. 11 (1): 37–50. doi:10.4072/rbp.2008.1.04.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. ^ Martinelli, Agustín G. (2008). "A new baurusuchid crocodyliform (Archosauria) from the Late Cretaceous of Patagonia (Argentina)". Comptes Rendus Palevol. 7 (6): 371–381. doi:10.1016/j.crpv.2008.05.002. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  4. ^ Candeiro, C. R. A., Martinelli, A. G., Avilla, L. S. & Rich, T. H. (2006). "Tetrapods from the Upper Cretaceous (Turonian-Maastrichtian) Bauru Group of Brazil: a reappraisal". Cretaceous Research. 27 (6): 923–946. doi:10.1016/j.cretres.2006.05.002.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ a b c d e Riff, D. (2011). "Baurusuchid crocodyliforms as theropod mimics: clues from the skull and appendicular morphology of Stratiotosuchus maxhechti (Upper Cretaceous of Brazil)". Zoological Journal of the Linnean Society. 163 (s1): s37–s56. doi:10.1111/j.1096-3642.2011.00713.x. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  6. ^ Campos, D.A. (1988). "Um novo Baurusuchidae (Reptilia, Crocodylia) do Cretáceo Superior do Estado de São Paulo". Anais da Academia Brasileira de Ciências. 27: 412. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  7. ^ Carvalho, I.S. (2004). "Uberabasuchus terrificus sp. nov., a new Crocodylomorpha from the Bauru Basin (Upper Cretaceous), Brazil" (PDF). Gondwana Research. 7 (4): 975–1002. doi:10.1016/S1342-937X(05)71079-0. ISSN 1342-937X. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  8. ^ Montefeltro, F.C. (2011). "A new baurusuchid (Crocodyliformes, Mesoeucrocodylia) from the Late Cretaceous of Brazil and the phylogeny of Baurusuchidae". PLoS ONE. 6 (7): e21916. doi:10.1371/journal.pone.0021916. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)CS1 maint: unflagged free DOI (link)
Stub icon

This article about a prehistoric archosaur is a stub. You can help Wikipedia by expanding it.

Retrieved from "https://en.wikipedia.org/w/index.php?title=Stratiotosuchus&oldid=478709631"