{{Short description|Extinct genus of mylagaulid rodent}} {{Automatic taxobox | fossil_range = {{Fossil range|Early Miocene}} | image = Mesogaulus ballensis.jpg | image_caption = Mandible of ''M. ballensis'' | taxon = Mesogaulus | authority = Riggs, 1899 | subdivision_ranks = Species | subdivision = * ''M.ballensis'' (Matthew, 1902) * ''M. paniensis'' (Riggs, 1899) | synonyms = ''Mylagaulus paniensis'' }}
'''''Mesogaulus''''' is a genus of mylagaulid rodent from Miocene North America.<ref>{{Cite web |title=Mindat.org |url=https://www.mindat.org/taxon-9246022.html |access-date=2025-10-24 |website=www.mindat.org}}</ref>
== Description == ''Mesogaulus'' is very basal morphologically, lacking horns of later mylagaulids like ''Ceratogaulus''. The genus also has large fourth premolars and hypsodont teeth, though not to the extremes of later mylagaulids. The first molar is elongated, whilst the third is more rotund.<ref name=":0">{{Cite book |last1=Field Columbian Museum. |url=https://www.biodiversitylibrary.org/item/21349 |title=Publication. Field Columbian Museum. Geological series |last2=Museum |first2=Field Columbian |last3=History |first3=Field Museum of Natural |date=1899 |publisher=The Museum |volume=v.1:no.4 (1899) |location=Chicago, U.S.A}}</ref> Similar to other members of their clade, ''Mesogaulus'' has a low, broad skull.<ref>{{Cite journal |last1=Cook |first1=Harold J. |last2=Gregory |first2=Joseph T. |date=1941 |title=Mesogaulus praecursor, a New Rodent from the Miocene of Nebraska |journal=Journal of Paleontology |volume=15 |issue=5 |pages=549–552 |jstor=1298811 |issn=0022-3360}}</ref><ref>{{Cite book |last1=Carnegie Museum |url=https://www.biodiversitylibrary.org/item/216920 |title=Annals of the Carnegie Museum |last2=Museum |first2=Carnegie |last3=History |first3=Carnegie Museum of Natural |date=2000 |publisher=Published by authority of the Board of Trustees of the Carnegie Institute |volume=v.69 (2000:Feb.-Nov.) |location=[Pittsburgh]}}</ref>
== Classification == ''Mesogaulus'' is currently grouped within Mesogaulinae, a potentially paraphyletic subfamily<ref>{{Cite journal |last1=Lu |first1=Xiaoyu |last2=Ni |first2=Xijun |last3=Li |first3=Lüzhou |last4=Li |first4=Qiang |date=2016-08-03 |title=Two New Mylagaulid Rodents from the Early Miocene of China |journal=PLOS ONE |language=en |volume=11 |issue=8 |article-number=e0159445 |doi=10.1371/journal.pone.0159445 |doi-access=free |issn=1932-6203 |pmc=4972310 |pmid=27486803 |bibcode=2016PLoSO..1159445L }}</ref> within Mylagaulidae containing the more basal members of the group.<ref name=":1">{{Cite journal |last=Hopkins |first=Samantha S. B. |date=2005-08-22 |title=The evolution of fossoriality and the adaptive role of horns in the Mylagaulidae (Mammalia: Rodentia) |journal=Proceedings. Biological Sciences |volume=272 |issue=1573 |pages=1705–1713 |doi=10.1098/rspb.2005.3171 |issn=0962-8452 |pmc=1559849 |pmid=16087426}}</ref> It has been suggested historically that ''Mesogaulus'' was ancestral to the later mylagaulines,<ref name=":0" /> though this is not supported by modern phylogenies.<ref name=":1" />
== References == {{Reflist}}{{Sciuromorpha|state=collapsed}}{{Taxonbar|from=Q17276952}}
Category:Sciuromorpha Category:Fossil taxa described in 1899 Category:Prehistoric rodent genera