View source for Nesodon

{{Expand Italian|topic=scitech|date=June 2022}}
{{Short description|Extinct genus of notoungulates}}
{{Automatic taxobox
| fossil_range = [[Miocene|Early Miocene]] ([[Deseadan]]-[[Friasian]])<br />~{{fossil range|23.03|15.5}}
| image = Nesodon imbricatus skeleton reconstruction.jpg
| image_caption = ''Nesodon imbricatus'' skeleton
| image2 = Nesodon imbricatus.JPG
| image2_caption = ''Nesodon imbricatus'' skull
| taxon = Nesodon
| authority = [[Richard Owen|Owen]], 1846
| type_species = †'''''Nesodon imbricatus'''''
| subdivision_ranks = Species
| subdivision_ref = <ref>Croft et al. (2004) pp. 4–5</ref>
| subdivision = * ''N. conspurcatus'' {{small|Ameghino 1887}}
* ''N. cornutus''
* ''N. imbricatus'' {{small|Owen 1846}}
* ''N. taweretus'' {{small|Forasiepi ''et al''. [[2014 in paleontology|2014]]}}
| synonyms_ref = <ref>McKenna and Bell (1997), p. 460</ref>
| synonyms = * ''Lithops'' {{small|[[Florentino Ameghino|Ameghino]] 1887}}
* ''Adelphotherium'' {{small|[[Florentino Ameghino|Ameghino]] 1887}}
* ''Gronotherium'' {{small|[[Florentino Ameghino|Ameghino]] 1887}}
* ''Atryptherium'' {{small|[[Florentino Ameghino|Ameghino]] 1887}}
* ''Rhadinotherium'' {{small|[[Florentino Ameghino|Ameghino]] 1887}}
* ''Protoxodon'' {{small|[[Florentino Ameghino|Ameghino]] 1887}}
* ''Acrotherium'' {{small|[[Florentino Ameghino|Ameghino]] 1891}}
* ''Palaeolithops'' {{small|[[Florentino Ameghino|Ameghino]] 1891}}
* ''Xotoprodon'' {{small|[[Florentino Ameghino|Ameghino]] 1891}}
* ''Nesotherium'' {{small|Mercerat 1891}}
}}

'''''Nesodon''''' ("[[island]] [[tooth]]")<ref name=etymo>[[Theodore Sherman Palmer|Palmer]] (1904) p. 457.</ref> is a genus of [[Miocene]] [[mammal]] belonging to the [[extinction|extinct]] [[Order (biology)|order]] [[Notoungulata]] which inhabited southern [[South America]] during the [[Late Oligocene]] to [[Miocene]] living from 29.0 to 16.3 [[Annum|Ma]] and existed for approximately {{Mya|29-16.3|million years}}.
<ref>[http://paleobackup.nceas.ucsb.edu:8110/cgi-bin/bridge.pl?action=checkTaxonInfo&taxon_no=43396&is_real_user=1 Paleobiology Database: ''Nesodon imbricatus'', Basic info.]{{Dead link|date=April 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> It had a relatively large size, weighing up to 554&nbsp;kg (1221&nbsp;lbs) and reaching 1.5 m in height.<ref>D.Patterson, Bruce (2012) ''Bones, Clones, and Biomes: The History and Geography of Recent Neotropical Mammals'' p.92</ref>

== Taxonomy ==
[[File:Nesodon.jpg|thumb|left|''N. imbricatus'' restoration by [[Charles R. Knight]], 1905]] 
''Nesodon'' was named by [[Richard Owen|Owen]] (1846). It was assigned to [[Toxodontidae]] by [[Robert L. Carroll|Carroll]] (1988). It was an early member of the family [[Toxodontidae]], which included the well-known [[Pleistocene]] genus ''[[Toxodon]]''. Like almost all toxodontids, ''Nesodon'' was [[endemism|endemic]] to [[South America]]. In particular, fossils of ''Nesodon'' are known from late early Miocene ([[Santacrucian]] [[SALMA]]) deposits of [[Argentina]] and [[Chile]].<ref name=distr>Croft et al. (2004), p. 5.</ref>

Three species of ''Nesodon'' are recognized including a larger species, ''N. imbricatus'', and a smaller species, ''N. conspurcatus''.<ref name=species>Croft et al. (2004), pp. 7–8.</ref> A poorly known and possibly invalid third species, ''N. cornutus'', was similar to ''N. imbricatus'' but may have had a small horn on its head. All species of ''Nesodon'' were larger than species of the contemporary toxodontid ''[[Adinotherium]]''.

The [[dentition]] of ''Nesodon'' shows features typical of living [[grazing]] (grass-eating) mammals, but a study of wear on the [[Tooth enamel|enamel]] of ''N. imbricatus'' suggests that it was a [[Browser (herbivore)|browser]] (leaf eater) that may have supplemented its diet with fruit or [[Bark (botany)|bark]].<ref name=diet>Townsend & Croft (2008) p. 225.</ref>

== Classification ==
[[File:Promegatherium_nanum.JPG|thumb|right|''[[Promegatherium|Promegatherium nanum]]'' and ''Nesodon''.]] 
In 2014, a study identifying a new species of ''Nesodon'', ''N. taweretus'', resolved the families phylogenetic relations, deriving the cladogram shown below:<ref name="AMFetal2014">{{Cite journal | doi = 10.1007/s12542-014-0233-5| title = New toxodontid (Notoungulata) from the Early Miocene of Mendoza, Argentina| journal = Paläontologische Zeitschrift| volume = 89| issue = 3| pages = 611–634| year = 2014| last1 = Forasiepi | first1 = A. A. M. | last2 = Cerdeño | first2 = E. | last3 = Bond | first3 = M. | last4 = Schmidt | first4 = G. I. | last5 = Naipauer | first5 = M. | last6 = Straehl | first6 = F. R. | last7 = Martinelli | first7 = A. N. G. | last8 = Garrido | first8 = A. C. | last9 = Schmitz | first9 = M. D. | last10 = Crowley | first10 = J. L. | s2cid = 129293436| url = http://sedici.unlp.edu.ar/bitstream/handle/10915/127531/Documento_completo.pdf?sequence=1 }}</ref>

{{clade| style=font-size:85%; line-height:85%
|1={{clade
 |1=''[[Pampahippus|Pampahippus arenalesi]]''
 |2={{clade
  |1={{clade
   |1=''[[Rhynchippus]]'' spp.
   |2={{clade
    |1=''[[Scarritia|Scarritia canquelensis]]''
    |2=''[[Leontinia|Leonitinia gaudri]]'' }} }}
  |label2=Toxodontidae
  |2={{clade
   |1=''[[Proadinotherium|Proadinotherium leptognathum]]''
   |2={{clade
    |1={{clade
     |1=''[[Adinotherium]]'' spp.
     |2={{clade
      |1='''''Nesodon taweretus'''''
      |2='''''Nesodon imbricatus''''' }} }}
    |2={{clade
     |1=''[[Palyeidodon|Palyeidodon obtusum]]''
     |2={{clade
      |1=''[[Hyperoxotodon|Hyperoxotodon speciosus]]''
      |2={{clade
       |1={{clade
        |1=''[[Nonotherium|Nonotherium henningi]]''
        |2=''[[Xotodon]]'' spp. }}
       |2={{clade
        |1={{clade
         |1=''[[Andinotoxodon|Andinotoxodon bolivariensis]]''
         |2={{clade
          |1={{clade
           |1=''[[Dinotoxodon|Dinotoxodon paranensis]]''
           |2=''[[Toxodon|Toxodon platensis]]'' }}
          |2={{clade
           |1=''[[Gyrinodon|Gyrinodon quassus]]''
           |2={{clade
            |1=''[[Ocnerotherium|Ocnerotherium intermedium]]''
            |2=''[[Hoffstetterius|Hoffstetterius imperator]]'' }} }} }} }}
        |2={{clade
         |1=''[[Posnanskytherium|Posnanskytherium desaguaderoi]]''
         |2={{clade
          |1=''[[Pisanodon|Pisanodon nazari]]''
          |2={{clade
           |1=''[[Pericotoxodon|Pericotoxodon platignathus]]''
           |2={{clade
            |1={{clade
             |1=''[[Calchaquitherium|Calchaquitherium mixtum]]''
             |2=''[[Mixotoxodon|Mixotoxodon larensis]]'' }}
            |2={{clade
             |1=''[[Paratrigodon|Paratrigodon euguii]]''
             |2=''[[Trigodon|Trigodon gaudri]]'' }} }} }} }} }} }} }} }} }} }} }} }} }} }}

== Distribution ==
Fossils of ''Nesodon'' have been found in:<ref name=FWNesodon>[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=43396 ''Nesodon''] at [[Fossilworks]].org</ref>
* [[Deseado Formation|Deseado]] and [[Santa Cruz Formation, Argentina|Santa Cruz Formation]], [[Argentina]]
* [[Chucal Formation|Chucal]] and [[Río Frías Formation]]s, [[Chile]]

== References ==
{{Reflist}}

=== Bibliography ===
* {{cite journal | last1 = Croft | first1 = D.A. | last2 = Flynn | first2 = J.J. | last3 = Wyss | first3 = A.R. | year = 2004 | title = Notoungulata and Litopterna of the Early Miocene Chucal Fauna, Northern Chile | url = https://archive.org/details/notoungulatalito50crof | journal = Fieldiana Geology | volume = 50 | issue = 1| pages = [https://archive.org/details/notoungulatalito50crof/page/1 1]–52 }}
* McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level.'' Columbia University Press, New York, 631 pp. {{ISBN|0-231-11013-8}}
* {{cite journal | last1 = Palmer | first1 = T.S. | year = 1904 | title = Index Generum Mammalium: a List of the Genera and Families of Mammals | journal = North American Fauna | volume = 23 | pages = 1–984 | doi=10.3996/nafa.23.0001| doi-access = free }}
* {{cite journal | last1 = Townsend | first1 = K.E.B. | last2 = Croft | first2 = D.A. | year = 2004 | title = Diets of notoungulates from the Santa Cruz Formation, Argentina: new evidence from enamel microwear | journal = Journal of Vertebrate Paleontology | volume = 28 | issue = 1| pages = 217–230 | doi = 10.1671/0272-4634(2008)28[217:DONFTS]2.0.CO;2 | s2cid = 85916583 }}

{{Meridiungulata|N.|state=collapsed}}
{{Taxonbar|from=Q846251}}

[[Category:Toxodonts]]
[[Category:Prehistoric placental genera]]
[[Category:Miocene mammals of South America]]
[[Category:Friasian]]
[[Category:Santacrucian]]
[[Category:Colhuehuapian]]
[[Category:Deseadan]]
[[Category:Neogene Argentina]]
[[Category:Fossils of Argentina]]
[[Category:Neogene Chile]]
[[Category:Fossils of Chile]]
[[Category:Fossil taxa described in 1846]]
[[Category:Taxa named by Richard Owen]]
[[Category:Austral or Magallanes Basin]]
[[Category:Santa Cruz Formation]]


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