{{Short description|Species of bivalve}} {{Speciesbox | image = Naturalis Biodiversity Center - ZMA.MOLL.418497 - Pyganodon lacustris (Lea, 1857) - Unionidae - Mollusc shell.jpeg | image_caption = | status = LC | status_system = IUCN3.1 | status_ref = <ref name=IUCN>{{cite iucn |last1=Bogan |first1=A.E. |last2=Cordeiro |first2=J. |year=2011 |title=''Pyganodon lacustris'' |volume=2011 |article-number=e.T189753A8766462 |doi=10.2305/IUCN.UK.2011-2.RLTS.T189753A8766462.en |access-date=30 December 2025}}</ref> | status2 = G4 | status2_system = TNC | status2_ref = <ref name=NS>{{cite NatureServe |id=2.113595 |title=''Pyganodon lacustris'' |access-date=30 December 2025}}</ref> | genus = Pyganodon | species = lacustris | authority = ([[Isaac Lea|Lea]], 1857) | synonyms_ref = }}
'''''Pyganodon lacustris''''' is a [[species]] of [[freshwater mussel]], an [[Aquatic animal|aquatic]] [[bivalve]] [[mollusk]] in the family [[Unionidae]], the river mussels. It is [[endemism|endemic]] to the [[United States]], where it is known to occur in [[Illinois]], [[Ohio]], [[Michigan]], [[New York (state)|New York]], [[Indiana]] and [[Wisconsin]]. It may also occur in the [[Great Lakes]] and into [[Canada]], however its full range has not been fully assessed.<ref name=IUCN/> It is commonly called the '''lake floater'''.<ref>{{Cite web|url=http://dnr.wi.gov/topic/EndangeredResources/Animals.asp?mode=detail&SpecCode=IMBIV54040|title=Lake Floater (Pyganodon lacustris)|website=dnr.wi.gov|access-date=2017-09-22}}</ref>
==Description== ''Pyganodon lacustris'' varies in size with the largest found to be around 20 centimeters (8 inches)<ref>{{Cite web|url=http://animaldiversity.org/accounts/Pyganodon_lacustris/|title=Pyganodon lacustris|website=Animal Diversity Web|language=en|access-date=2017-09-22}}</ref> with an average of around 10 centimeters (4 inches). They have an elliptical shape and is generally long and thin. The ventral is straight to slightly curved and color ranges from yellow-green in adolescence to dark brown or black in adulthood.<ref>{{Cite web|url=https://mnfi.anr.msu.edu/explorer/species.cfm?id=19860|title=Pyganodon lacustris (Lake floater) - MNFI Rare Species Explorer|website=mnfi.anr.msu.edu|access-date=2017-09-22}}</ref>
==References== {{Reflist}}
{{Taxonbar|from=Q3805091}}
[[Category:Pyganodon|lacustris]] [[Category:Bivalves described in 1857]]
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