{{Short description|Species of bivalve, freshwater mussel}} {{Speciesbox | image = Naturalis Biodiversity Center - RMNH.MOL.327070 - Obovaria olivaria (Rafinesque, 1820) - Unionidae - Mollusc shell.jpeg | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn status 16 November 2021">{{cite iucn |author=Cummings, K. |author2=Cordeiro, J. |date=2012 |title=''Obovaria olivaria'' |volume=2012 |article-number=e.T15022A547105 |doi=10.2305/IUCN.UK.2012.RLTS.T15022A547105.en |access-date=16 November 2021}}</ref> | status2 = G4 | status2_system = TNC | status2_ref = <ref name="nserveolivaria">{{cite NatureServe |id=2.113791 |title=''Obovaria olivaria'' |access-date=7 March 2023}}</ref> | genus = Obovaria | species = olivaria | authority = ([[Constantine Samuel Rafinesque-Schmaltz|Rafinesque]], 1820) | synonyms = {{collapsible list| *''Amblema olivaria'' <small>Rafinesque, 1820</small> *''Amblema olivaria'' subsp. ''dilatata'' <small>Rafinesque, 1820</small> *''Amblema olivaria'' subsp. ''fasciolaris'' <small>Rafinesque, 1820</small> *''Margarita'' (''Unio'') ''ellipsis'' <small>(I.Lea, 1827)</small> *''Margaron'' (''Unio'') ''ellipsis'' <small>(I.Lea, 1827)</small> *''Obovaria'' (''Pseudoon'') ''ellipsis'' <small>(I.Lea, 1827)</small> *''Unio ellipsis'' <small>I.Lea, 1827</small> *''Unio pealei'' <small>I.Lea, 1871</small>}} |synonyms_ref=<ref>{{GBIF|taxon=''Obovaria olivaria'' (Rafinesque, 1820)|id=2288371|access-date=7 March 2023}}</ref> }}
'''''Obovaria olivaria''''' is a [[species]] of [[freshwater mussel]], an [[aquatic animal|aquatic]] [[bivalve]] [[mollusk]] in the family [[Unionidae]], the river mussels. It is commonly referred to as '''hickorynut'''.<ref>{{Cite web |title=''Obovaria olivaria'' (Hickorynut)|url=https://mnfi.anr.msu.edu/species/description/12378/Obovaria-olivaria |access-date=7 March 2023|website=Michigan Natural Features Inventory|publisher=Michigan State University}}</ref>
The species is native to eastern North America. It is found in the drainages of the [[Ohio River]], the [[St. Lawrence River]], and the [[Great Lakes]]. It is known to use only [[sturgeon]]s as larval hosts.<ref name=":0">{{Cite journal |last1=Bucholz |first1=Jamie R. |last2=Sard |first2=Nicholas M. |last3=VanTassel |first3=Nichelle M. |last4=Lozier |first4=Jeffrey D. |last5=Morris |first5=Todd J. |last6=Paquet |first6=Annie |last7=Zanatta |first7=David T. |date=2022-01-26 |title=RAD-tag and mitochondrial DNA sequencing reveal the genetic structure of a widespread and regionally imperiled freshwater mussel, ''Obovaria olivaria'' (Bivalvia: Unionidae) |journal=Ecology and Evolution |volume=12 |issue=1 |article-number=e8560 |doi=10.1002/ece3.8560|doi-access=free|issn=2045-7758 |pmc=8794720 |pmid=35127054}}</ref>
Although the species is considered of least concern by the [[International Union for Conservation of Nature|IUCN]], it is considered endangered across much of its native habitat. The species is especially threatened near the Great Lakes and in [[Canada]].<ref name="nserveolivaria"/><ref name=":0" /> According to [[NatureServe]], the hickorynut is presumed to be [[extirpated]] in [[Kansas]], [[Alabama]] and [[Ohio]] and may have been extirpated from [[Nebraska]] and [[Pennsylvania]].<ref name="nserveolivaria"/>
==References== {{Reflist}}
{{Taxonbar|from=Q3014883}}
[[Category:Molluscs of the United States]] [[Category:Obovaria|olivaria]] [[Category:Bivalves described in 1820]] [[Category:Taxa named by Constantine Samuel Rafinesque]] [[Category:Taxonomy articles created by Polbot]]
{{Unionidae-stub}}