View source for Ostrea edulis

{{speciesbox
| name = ''Ostrea edulis''
| image = Ostrea edulis 01.jpg
| image_caption = Valves of ''Ostrea edulis''
| fossil_range = {{fossil range|15.97|0|[[Miocene]] – Recent}}
| genus = Ostrea
| species = edulis
| authority = [[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]]<ref name="linnaeus">{{cite book|last=Linnaeus|first=Carl|title=[[Systema Naturae]]|edition=10|year=1758|location=[[Uppsala]]|language=Latin|publisher=Linnaeus}}</ref><ref name="itis">{{cite web
|url=https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=all&search_value=Ostrea+edulis&search_kingdom=every&search_span=exactly_for&categories=All&source=html&search_credRating=All
|title=ITIS Standard Report Page: Ostrea edulis|accessdate=2008-08-06}}</ref>
}}

'''''Ostrea edulis'',''' commonly known as the '''European flat oyster''', is a species of [[oyster]] native to [[Europe]]. In the British Isles, regional names include '''[[Colchester]] native oyster''', '''mud oyster''', or '''edible oyster'''. In France, ''Ostrea edulis'' are known as ''huîtres plates'' (flat oysters) except for those that come from the Belon River estuary in [[Brittany]], France, which are known as ''''Belons'''<nowiki/>'.<ref name="pangeashellfish.com">{{Cite news|url=http://www.pangeashellfish.com/blog/history-of-belon-oysters-rare-or-not|title=Where do Belon Oysters come from and are they that rare?|work=Pangea Shellfish Company {{!}} Oyster and Shellfish Wholesale|access-date=2018-07-17|language=en-US}}</ref>

The fossil record of this species dates back to the [[Miocene]] (age range: 15.97 to 0.012 million years ago). These fossils have been found in Belgium, Italy, the Netherlands, Egypt, Greece, Spain, the United Kingdom, Austria, France and Germany.<ref>[http://fossilworks.org/bridge.pl?a=taxonInfo&taxon_no=89009 Fossilworks]</ref>

==Description==
When mature, ''O. edulis'' adults range from {{convert|3.8|to|11|cm|in}} across.<ref name="jackson">{{cite web|url=http://www.marlin.ac.uk/species/Ostreaedulis.htm|author=Jackson, Angus|title=Basic information for Ostrea edulis (Native oyster)|publisher=Plymouth: Marine Biological Association of the United Kingdom|date=2008-07-14|accessdate=2008-08-07|archive-url=https://web.archive.org/web/20080315205955/http://www.marlin.ac.uk/species/Ostreaedulis.htm|archive-date=2008-03-15|dead-url=yes|df=}}</ref>

Shells are oval or pear shaped, white, yellowish or cream in colour, with a rough surface showing pale brown or bluish concentric bands on the right valve. The two valves are quite different in shape and size, as the left one is concave and fixed to the substratum, while the right one is almost flat and fits inside the left. The inner surface is smooth, whitish or bluish-grey.<ref>{{Cite web|url=http://www.fao.org/fishery/culturedspecies/Ostrea_edulis/en|title=FAO Fisheries & Aquaculture Ostrea edulis|last=|first=|date=|website=www.fao.org|language=en|archive-url=|archive-date=|dead-url=|access-date=2018-07-09}}</ref>

[[File: Ostreidae - Ostrea edulis.JPG|thumb|240px|left|Fossil of ''Ostrea edulis'' from Pliocene of Italy]]

==Biology==
''Ostrea edulis'' are gregarious molluscs that start their lives as males. They mature sexually after eight–ten months and may change sex depending on the water temperature. Usually the lifespan can reach about six years, with a maximum of 15 years. Adult oysters feed by filtration.<ref>{{Cite web |url=http://www.arkive.org/native-oyster/ostrea-edulis/ |title=Arkive.org |access-date=2015-06-08 |archive-url=https://web.archive.org/web/20150608173614/http://www.arkive.org/native-oyster/ostrea-edulis/ |archive-date=2015-06-08 |dead-url=yes |df= }}</ref> [[File:Ostrea edulis 001.png|240px|thumb|right|''Ostrea edulis''; a) labial palpi b) gills c) mantle d) junction of the two folds of the mantle e) large adductor muscle f) the shell]]

==Distribution==
The species naturally ranges along the western and southern coasts of [[Europe]] from [[Norway]] to [[Morocco]] and including most of the [[British Isles]] and the [[Mediterranean]] coast.<ref name="fao">{{cite web|url=http://www.fao.org/fishery/culturedspecies/Ostrea_edulis|title=FAO Fisheries &amp; Aquaculture Ostrea edulis|accessdate=2008-08-06|publisher=FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS}}</ref>  Naturally viable populations have appeared in eastern [[North America]] from [[Maine]] to [[Rhode Island]] subsequent to artificial introduction in the 1940s and 1950s.<ref name="fao"/>

==Habitat==
''Ostrea edulis'' can be found in estuarine and shallow coastal water with hard substrata of mud and rocks.<ref>[http://www.marlin.ac.uk/speciesfullreview.php?speciesID=3997 MarLIN]</ref>

==Human use==
[[Image:Y.P. Ostrea edulis 1950-2003.gif|thumb|190px|left|Worldwide ''O. edulis'' harvest in tonnes, 1950–2003]]''Ostrea edulis'' has been harvested throughout Europe as an important food source since prehistory. During Roman occupation of Britain ''O. edulis'' oysters were exported in large quantities back to Italy.<ref>{{Cite web|url=http://eol.org/pages/449502/details|title=European Flat Oyster – Ostrea edulis – Details – ''Encyclopedia of Life''|website=Encyclopedia of Life|language=en|access-date=2017-10-28}}</ref> However, due to their robust nature and ease of cultivation the [[Pacific oyster]]s, ''[[Crassostrea gigas]]'', account for more than 75 percent of Europe's oyster production.

European flat oysters are famously grown in Brittany, France. The true Belon oyster is cultivated in the Belon River, France, and has the [[Appellation d'origine contrôlée|AOC]] protected name.<ref>{{Cite web|url=http://www.chefs-resources.com/seafood/oysters/atlantic-oysters/belon-oysters-maine/|title=Belon Oysters – Maine|website=www.chefs-resources.com|access-date=2017-10-28}}</ref> In the 1950s, Dutch scientists artificially introduced Belon oyster seed into the waters around [[Maine]] in hopes to establish a viable stock. The initial project was abandoned but ten years later natural colonies of flat oysters were found in the wild.<ref name="pangeashellfish.com"/> Many North American suppliers use the name 'Belon' to species that are found in the wild throughout the [[United States]].

[[File:European Flat Oyster.jpg|thumb|
Loch Ryan oysters are sourced from Scotland's only commercial European flat oyster bed.
]]

''Ostrea edulis'' is now also being [[mariculture]]d in the states of [[California]], [[Maine]], and [[Washington (U.S. state)|Washington]] in the United States. The species once dominated European oyster production but disease, pollution, and overfishing sharply reduced the harvest.<ref name="fao"/>

U.S. [[Oyster farming|oyster growers]] farm ''O. edulis'' in small quantities on both coasts. They are prized for their unique tannic seawater flavour, sometimes described as dry and metallic, and are more expensive than other American oysters.<ref name="fao"/>  The flavour is considered excellent for eating raw on the half shell.<ref name="time">{{cite news|url=http://www.time.com/time/magazine/article/0,9171,874019,00.html|title=Ostrea Edulis &amp; Others – TIME|publisher=[[''Time'']]|accessdate=2008-08-07 | date=1964-07-31}}</ref><ref>{{cite web|url=http://www.kellyoysters.com/oysters.html|title=Kelly Galway Oysters|accessdate=2008-08-07|archive-url=https://web.archive.org/web/20090423124106/http://www.kellyoysters.com/oysters.html|archive-date=2009-04-23|dead-url=yes|df=}}</ref>

The abductor muscle of the European flat in combination with the shape of the shell results in a somewhat weaker seal compared with other oyster species. It is common practice to use rubber bands to prevent oysters from spilling their liquor and dehydrating in storage before consumption.<ref>{{Cite news|url=http://www.pangeashellfish.com/blog/history-of-belon-oysters-rare-or-not|title=Where do Belon Oysters come from and are they that rare?|work=Pangea Shellfish Company {{!}} Oyster and Shellfish Wholesale|access-date=2017-10-28|language=en-US}}</ref>

==See also==
* [[Locmariaquer#History of oyster farming]]

==References==
{{Reflist}}

==External links==
{{Commons category}}
* [https://web.archive.org/web/20100701043108/http://www.ukbap.org.uk/UKPlans.aspx?ID=495 UK Biodiversity Action Plan]

{{Oysters}}
{{Edible molluscs}}
{{Taxonbar|from=Q729678}}

[[Category:Ostrea]]
[[Category:Edible bivalves]]
[[Category:Commercial molluscs]]
<!-- [[Category:Seafood]] included in "Category:Marine edible bivalves" -->
[[Category:Molluscs described in 1758]]
[[Category:Taxa named by Carl Linnaeus]]