Cracking pearlymussel

{{Short description|Species of bivalve}} {{Speciesbox | image = Hemistena lata.jpg | image_caption = | status = CR | status_system = IUCN2.3 | status_ref = <ref name="iucn status 20 November 2021">{{cite iucn |author=Bogan, A.E. |date=1996 |title=''Hemistena lata'' |volume=1996 |article-number=e.T9907A13025910 |doi=10.2305/IUCN.UK.1996.RLTS.T9907A13025910.en |access-date=20 November 2021}}</ref> | status2=LE | status2_system=ESA | status2_ref=<ref>{{cite web|url=https://ecos.fws.gov/ecp/species/4130|title=Cracking pearlymussel (''Hemistena lata'')|website=Environmental Conservation Online System|publisher=U.S. Fish & Wildlife Service|access-date=6 April 2023}}</ref><ref>{{Federal Register|54|39850}}</ref> | genus = Hemistena | parent_authority = Rafinesque, 1820 | display_parents = 2 | species = lata | authority = ([[Constantine Samuel Rafinesque|Rafinesque]], 1820) | synonyms = *''Lastena lata'' (Rafinesque, 1820) *''Anodonta lata'' Rafinesque, 1820 *''Unio dehiscens'' Say, 1829 *''Unio oriens'' Lea, 1831 *''Odatelia radiata'' Rafinesque, 1832 *''Unio hildrethi'' Delessert, 1841 *''Unio dehiscens'' subsp. ''oriensopsis'' de Gregorio, 1914 | synonyms_ref = <ref>{{ITIS|id=80350|taxon=''Hemistena lata'' (Rafinesque, 1820)|access-date=6 April 2023}}</ref> }}

The '''cracking pearlymussel''' ('''''Hemistena lata''''') is an [[endangered species]] of [[freshwater mussel]], an [[Aquatic animal|aquatic]] [[bivalve]] [[mollusk]] in the family [[Unionidae]].

This species is native to the United States, where it remains only in [[Tennessee]] and [[Virginia]]. It was originally distributed in the [[Ohio River]], [[Cumberland River]] and [[Tennessee River]] systems, but it has been extirpated from most of its previous range.

Parmalee and Bogan reported that there were still populations in the [[Clinch River]] in Tennessee.<ref name="Parmalee">Parmalee, P. W. and Bogan, A. E. (1998) ''The Freshwater Mussels of Tennessee''. Knoxville, TN: [http://utpress.org/ University of Tennessee Press].</ref> Other populations that are known to survive are located in the [[Powell River (Virginia)|Powell]] and [[Elk River (North Carolina)|Elk]] Rivers.<ref>{{cite book |editor=C. J. Moseley |year=1990 |chapter=Cracking Pearly Mussel |title=The Official World Wildlife Fund Guide to Endangered Species of North America |url=https://archive.org/details/officialworldwil03amer |url-access=registration |location=Washington, D.C. |publisher=[[Beacham Publishing Inc.]] |series=volume III |pages=[https://archive.org/details/officialworldwil03amer/page/1447 1447–1448]|isbn=978-0-933833-17-3 }}</ref> ==Shell description== These mussels have thin, fairly weak, elongated [[Mollusc shell|shells]]. The shells may reach up to {{convert|69|mm}} in height The outer coloring of the shell varies from yellow to brown, while the interior of the shell is pale bluish white, with a purple beak cavity.<ref name="Parmalee" />

==Ecology== This species spends its adult life buried under the sand or mud at the bottom of medium-sized, flowing rivers. The females capture sperm released into the water by males. They store the sperm until they need them to fertilize their eggs. After fertilization, the females release the larvae into the river, where the larvae attach themselves to fish. Once the larva matures into juveniles with shells, they leave their host fish and drop into the sediment, where they bury themselves.<ref name="fwsspecies">{{cite web |publisher=[[U.S. Fish and Wildlife Service]] |url=https://www.fws.gov/species/cracking-pearly-mussel-hemistena-lata |title=Cracking Pearly Mussel |access-date=January 24, 2024}}</ref> This process, therefore, requires an environment with ample fish to act as hosts. They prefer relatively shallow (usually less than 2 ft deep) water with a moderate current.<ref name="Parmalee" />

==Conservation== The main threats to the continued existence of this species are habitat changes due to [[dam]]ming of rivers, [[silting]] of rivers due to erosion caused by construction, farming and logging, and poisoning due to agricultural and industrial [[pollution]].<ref name="fwsspecies" /> The U.S. Fish and Wildlife Service has created a recovery plan for this species.<ref>{{cite web |author=R. C. Biggins |year=1991 |url=https://ecos.fws.gov/docs/recovery_plan/Cracking%20Pearlymussel%201991_2.pdf |title=Recovery Plan for Cracking Pearlymussel (''Hemistena (=Lastena) lata'')}}</ref> As of the most recent 5 year review, the cracking pearlymussel is still critically endangered and has not met the recovery goals.<ref>{{cite web |author=U.S. Fish & Wildlife Service Southeast Region |year=1918 |url=https://ecos.fws.gov/docs/five_year_review/doc6300.pdf |title=Cracking Pearlymussel ''Hemistena lata'' (Rafinesque, 1820) 5 year review: Summary and Evaluation}}</ref>

==References== {{Reflist}}

[[Category:Unionidae]] [[Category:Bivalves described in 1820]] [[Category:Bivalves of North America]] [[Category:Taxa named by Constantine Samuel Rafinesque]] [[Category:ESA endangered species]]