View source for Velvet crab

{{Short description|Species of crab}}
{{Speciesbox
| name = Velvet crab
| image = Etreinte d'étrilles (Necora puber) (Ifremer 00557-66881 - 20149).jpg
| image_caption = Velvet crabs among ''[[Corynactis]]'' anemones in [[Brest, France]]
| parent_authority = [[Lipke Holthuis|Holthuis]], 1987
| genus = Necora
| species = puber
| authority = ([[Carl Linnaeus|Linnaeus]], [[12th edition of Systema Naturae|1767]])
| synonyms = {{hidden|List|
{{Species list
| Cancer puber | Linnaeus, 1767
| Liocarcinus puber | (Linnaeus, 1767)
| Macropipus puber | (Linnaeus, 1767)
| Portunus puber | (Linnaeus, 1767)
| Cancer velutinus | Pennant, 1777
}}
}}
| synonyms_ref = {{Sfn|Adema|1991|p=164}}
}}
The '''velvet crab''' ('''''Necora puber'''''), also known as the '''velvet swimming crab''' or '''devil crab''', is a species of [[crab]] from the North-East Atlantic and the Mediterranean.

== Classification ==
[[File:Œil à facette de l'étrille commune (Necora puber) (Ifremer 00563-67528 - 23736).jpg|thumb|Velvet crabs have distinctive, bright red eyes, for which they are sometimes called "devil crabs".]]
The velvet crab was first [[Species description|formally described]] in 1767 by [[Carl Linnaeus]] in the second part of the first volume of [[12th edition of Systema Naturae|the twelfth edition]] of his definitive work ''[[Systema Naturae]].'' Linnaeus gave it the name ''Cancer puber;''{{Sfn|Linneaus|1767|p=1046}} at the time, all crabs were classified indiscriminately into the genus ''[[Cancer (genus)|Cancer]].''{{Sfn|Holthuis|1987|p=1}} ''Necora puber'' is commonly known as the "velvet crab", the "velvet [[swimming crab]]", and the "devil crab", the latter due to its aggressive behaviour and bright red eyes.{{Sfn|Trewhella|Hatcher|2021|p=119}}{{Sfn|Barreto|Bailey|2013|pp=48–9}} In the Scottish fishing industry, they are sometimes known just as "velvets",{{Sfn|Barreto|Bailey|2013|pp=48–9}} and other less pervasive common names include the "velvet fiddler crab" the "lady crab", and the "Kerry witch".{{Sfn|Ingle|1980|pp=92–3}}

Linnaeus provided a very brief Latin description ‒ "vague and unsatisfactory", according to [[Lipke Holthuis]].{{Sfn|Linneaus|1767|p=1046}}{{Sfn|Holthuis|1987|p=8}} In fact, the identity of Linnaeus's crab in unclear, as no [[type material]] was assigned and the description given seems to more closely resemble [[Polybius corrugatus|''Polybius corrugatus'']].{{Sfn|Holthuis|1987|p=1}} Since Linneaus' initial 1767 description, the velvet crab has been reclassified four times: first into ''[[Portunus]]'' by [[Johan Christian Fabricius|Fabricius]] in 1798, a classification which stood until 1958, when it was transferred to ''[[Macropipus]]'' by Holthuis and Gottlieb. In 1981 [[Raymond B. Manning|Manning]] and Holthuis moved it to ''[[Liocarcinus]]'',{{Sfn|Adema|1991|p=164}} and six years later Holthuis reclassified the species into an entirely new genus, ''Necora'', of which the velvet crab is the [[Monotypic taxon|only species]]. This classification still stands. The genus name ''Necora'' comes from the local word for the crabs in [[Galicia (Spain)|Galicia]].{{Sfn|Holthuis|1987|p=3}} Several species names described by other taxonomists have since been [[Synonym (taxonomy)|synonymised]] with ''Necora puber''.{{Sfn|Ingle|1980|pp=92–3}}

===Phylogenetics===
Recent [[phylogenetic]] studies of the [[Portunoidea]] and related groups have considered ''Necora'' several times in their research. ''Necora'' is usually grouped with members of the genera ''[[Bathynectes]]'', ''[[Liocarcinus]]'', ''[[Macropipus]]'', ''[[Polybius (crab)|Polybius]]'', and ''[[Thia]]''.{{efn|''Thia'', like ''Necora'', contains only one species.}}

A phylogenetic study published in ''[[Frontiers in Zoology]]'' in 2022 used both [[maximum parsimony]] and [[bayesian inference]] and analysed morphological characteristics placed ''Necora puber'' in a monophyletic [[Carcinidae]] clade. Of the surveyed species, ''Necora'' was [[sister group|sister]] to a ''[[Macropipus rugosus]]'' / ''Thia'' grouping.{{sfn|Hazerli|Höpel|Richter|2022|p=43}} However, a study using [[nuclear DNA]] from 2009 placed ''Thia'' sister to a clade that includes ''Necora'', but also species from ''Macropipus'', ''Liocarcinus'', ''Polybius'', and ''Bathynectes''. The authors of the 2009 study noted that the conventional classifications of the [[Portunoidea]] and [[Canceroidea]] have recently been challenged, and some morphological traits – especially those of the [[carapace]] and the [[chelae]] – can be affected by [[convergent evolution]].{{Efn|The 2022 analysis focused on characters of the [[axial skeleton]], the [[pereiopod]]s, and the crabs' musculature.}} The 2016 study kept ''Necora'' in the [[Polybiidae]].{{sfn|Schubart|Reuschel|2009|pp=542 & 545}} A yet earlier (2001) study using [[mitochondrial DNA]] of 46 species paired ''Necora'' with ''[[Bathynectes maravigna]]'', close to ''Macropipus tuberculatus'' and ''Thia''.{{sfn|Schubart|Reuschel|2009|p=540}}

{| style="margin-left: auto; margin-right: auto;"
|{{Cladogram
|align=center
|cladogram=
{{clade
|1=
{{clade
|1=''Liocarcinus'' and ''Polybius'' spp.
|2={{clade
   |1=''{{azure|Bathynectes maravigna}}''
   |2={{clade
     |1='''''{{dark red|Necora puber}}'''''
     |2={{clade
          |1=''{{green|Macropipus rugosus}}''
          |2=''{{purple|Thia scutellata}}''
         }}
      }}
    }}
}}
}}

|caption=After Hazerli et al, 2022.
}}
|
{{Cladogram
|align=center
|cladogram=
{{clade
|1=
{{clade
|1=''{{purple|Thia scutellata}}''
|2={{clade
   |1='''''{{dark red|Necora puber}}''''' 
   |2=''{{azure|Bathynectes maravigna}}''
   |3=''{{verdyre|Macropipus tuberculatus}}''
   |4=''Liocarcinus'' and ''Polybius'' spp.
}}
}}
}}

|caption=After Schubert & Reuschel, 2009.
}}
|-
|}

== Distribution ==
In the [[British Isles]], velvet crabs are found from [[Orkney]] around Scotland, England, Wales, and Ireland. They also live in the nearby [[German Bight]] and in parts of the [[West Frisian Islands|West Frisian Islands.]]{{Sfn|Ingle|1980|pp=92–3}}
[[File:Etrille(Necora).jpg|thumb|350x350px|Bottom, top, and front views of one dried velvet crab specimen.]]

== Description ==
Velvet crabs have a dark, flattened [[carapace]] which ranges from black to brown in colour and is usually around 6.5 cm long{{Sfn|Ingle|1980|pp=92–3}} and up to 10 cm across, weighing up to 250 grams.{{Sfn|Hearn|2004|p=1}} The carapace is [[wikt:pubescent|pubescent]] with short yellowish hairs providing a velvety texture.{{Sfn|Holthuis|1987|p=3}}{{Sfn|Cuvier|Latreille|1834|p=165}} Tubercles are scattered across the upper surface, with a higher concentration towards the front. The frontal part of the crab's underside has some tubercles as well and is densely hairy. The front of the carapace is mostly straight and bends slightly inwards at the centre line; the front edge bears seven to ten tooth-like indentations. The [[Chelae|claw]]-bearing legs (the chelipeds) also have short hairs and are of equally short length. The "wrist" is armed with a spine on its outer side.{{Sfn|Holthuis|1987|pp=3–7}}{{Sfn|Ingle|1980|pp=92–3}}

== Conservation ==
Velvet crabs are "very common".{{Sfn|Trewhella|Hatcher|2021|p=119}} 

=== French fisheries ===
In France, velvet crabs are considered a delicacy.{{Sfn|Cuvier|Latreille|1834|p=165}} Fisheries in south [[Brittany]], France's main producers of velvet crabs, suffered in the late 20th century due to mass mortality events; between 1984 and 1988 the catch dropped by 96%. The decline was attributed to infections by [[Dinoflagellate|dinoflagellates]] which a 1996 investigation tentatively identified as belonging to the genus ''[[Hematodinium]].''<ref>Wilhelm, G. and Mialhe, E, 1996. "[https://www.int-res.com/articles/dao/26/d026p213.pdf Dinoflagellate infection associated with the decline of ''Necora puber'' crab populations in France]", published in ''Diseases of Aquatic Organisms'' volume 26.</ref>
[[File:Velvet crabs - geograph.org.uk - 827537.jpg|thumb|A fisherman in [[Lybster]], Scotland, sorts velvet crabs for export. Scotland is today Europe's largest velvet crab fisher.]]

===British fisheries===
{{See also|Crabs of the British Isles#Fisheries}}
Velvet crabs are traditionally eaten in France and Spain, and are commercially important for the [[British Isles]], although they were there once regarded as pests.{{sfn|Hinchliff|Dick|Sigwart|Gilmore|2015|p=6}} In the [[United Kingdom]], the velvet crab catch is regulated by ''The Undersized Velvet Crabs Order 1989,'' which enforced a [[minimum landing size]] of 6.5 cm across the carapace, although it is also customary to throw back egg-bearing females when caught.{{Sfn|Hearn|2004|p=2}}

Targeted fishing for the crabs is a recent phenomenon in Ireland, having started in the 1980s in response to increased demand due to the collapse of the Spanish velvet crab fisheries and thus of the southern European stocks.{{sfn|Collins|Ward|Bateman|Cheslett|2022|p=167}} Velvet crabs are found all around Ireland, where the crabs are often taken as [[bycatch]] from [[edible crab]] and [[lobster]] fisheries, but they are fished for in the [[Irish Sea]].{{sfn|Hinchliff|Dick|Sigwart|Gilmore|2015|p=6}}{{sfn|Collins|Ward|Bateman|Cheslett|2022|p=167}} Between 2006 and 2014, the volume of velvet crabs caught in Ireland decreased by nearly 100 tonnes, down from 230 tonnes, prompting concerns from fishermen and the [[fishing industry]]. In 2003, the velvet crab catch in Ireland was worth £5,812 a year.{{sfn|Hinchliff|Dick|Sigwart|Gilmore|2015|p=6}} 

Velvet crab fisheries in Scotland have a similar history: the crabs were once regarded as pests, but the 1980s supply crisis prompted the emergence of a Scottish fishery. Today, Scotland is in fact Europe's largest fisher of velvet crabs, although the crabs are rarely targeted specifically and are caught alongside edible crabs and lobster. In 2011, the Scottish velvet crab fishery caught £5.8 million worth of crabs, or more than two thousand tonnes. The most productive areas are around the Scottish islands and west coast, the fishery having started around the [[Hebrides]] and [[Orkney]] islands, but an east coast industry is also emerging. Although the industry is regulated, the crabs may be being overfished in the [[Firth of Clyde]], Orkney and South [[Minch]].{{Sfn|Barreto|Bailey|2013|pp=48–9}}

In England, the velvet crab fishery reached its peak in 2006, and in 2011 around 200 tonnes of crabs worth £290,000 were landed. Velvet crabs are also found around the [[Isle of Man]], but it is not of primary interest to the fishing industry there.<ref>{{Cite book |url=http://sustainable-fisheries-wales.bangor.ac.uk/documents/ICESWGCRAB2012Report_000.pdf |title=Report of the Working Group on the Biology and Life History of Crabs |publisher=[[International Council for the Exploration of the Sea]] |year=2012 |pages=9 & 33}}</ref>

==Notes==

{{notelist}}

==Citations==
{{Reflist}}

==Bibliography==
{{div col|small=yes}}
*Adema, J.P.H.M., 1991. "De Krabben van Nederland en Belgie" (in Dutch), published by the [[Nationaal Natuurhistorisch Museum]]. {{ISBN|90-73239-02-8}} {{SfnRef inline|Adema|1991}}
*Barreto, Elisa and Bailey, Nick, 2013. [https://www.gov.scot/binaries/content/documents/govscot/publications/statistics/2013/09/fish-shellfish-stocks-2013/documents/00434286-pdf/00434286-pdf/govscot%3Adocument/00434286.pdf "Fish and Shellfish Stocks, 2013 Edition"], published by the [[Scottish Government]]. {{ISBN|978-1-78256-861-2}}; {{ISSN|2044-0340}} {{SfnRef inline|Barreto|Bailey|2013}}
*Collins, Evelyn ''et al.'', 2022. "High prevalence of ''Paramarteilia canceri'' infecting velvet swimming crabs ''Necora puber'' in Ireland", published in ''Diseases of Aquatic Organisms'' volume 148. {{doi|10.3354/dao03652|doi-access=free}} [https://creativecommons.org/licenses/by/4.0/ CC-BY 4.0] {{SfnRef inline|Collins|Ward|Bateman|Cheslett|2022}}
*[[Georges Cuvier|Cuvier, Georges]] and [[Pierre André Latreille|Latreille, Pierre André]], 1834. ''The Animal Kingdom'', vol. 3. {{Doi|10.5962/bhl.title.39976}} {{OCLC|7349472}}{{SfnRef inline|Cuvier|Latreille|1834}}
*Hazerli, Dennis; Höpel, Christoph Gert; and Richter, Stefan, 2022. "New insights into the evolution of portunoid swimming crabs (Portunoidea, Heterotremata, Brachyura) and the brachyuran axial skeleton", published in ''[[Frontiers in Zoology]]'' volume 19, no. 1 by [[BioMed Central|BMC]]. {{doi|10.1186/s12983-022-00467-8|doi-access=free}}. [https://creativecommons.org/licenses/by-sa/4.0/ CC-BY-SA 4.0] {{SfnRef inline|Hazerli|Höpel|Richter|2022|p=43}}
*Hearn, Alex R., 2004. "Reproductive biology of the velvet swimming crab, ''Necora puber'' (Brachyura: Portunidae), in the Orkney Islands, UK" published in ''Sarsia'' volume 89. {{SfnRef inline|Hearn|2004}}
*Hinchliff, Laura; Dick, Jaimie; Sigwart, Julia; and Gilmore, Lynn, 2015. ''The velvet swimming crab (Necora puber) fishery in Northern Ireland: a study of populations and welfare to enhance sustainability'', published by [[Queen’s University Belfast]] and [[Seafish (non-departmental public body)|Seafish]]. {{isbn|978-1-906634-94-0}} {{SfnRef inline|Hinchliff|Dick|Sigwart|Gilmore|2015}}
*Holthuis, Lipke B., 1987. "[https://repository.naturalis.nl/pub/317926/ZM1987061001.pdf ''Necora'', a new genus of European swimming crabs (Crustacea, Decapoda, Portunidae) and its type species, ''Cancer puber'' L., 1767]", published in ''[[Zoologische Mededelingen]]'' volume 61 no. 1 by the [[Rijksmuseum van Natuurlijke Historie|National Museum of Natural History, Leiden]]. {{ISSN|0024-0672}}{{SfnRef inline|Holthuis|1987}}
*Ingle, Raymond W., 1980. ''British Crabs'', published by [[Oxford University Press]]. {{Internet Archive ID|britishcrabs0000ingl}}{{SfnRef inline|Ingle|1980}}
*Linnaeus, Carl, 1767. ''Systema Naturae'', 12th edition, vol. 1 part 2. {{Doi|10.5962/bhl.title.37256}} {{SfnRef inline|Linneaus|1767}}
*Schubart, Christoph D. and Reuschel, Silke, 2009. "[https://ia600108.us.archive.org/view_archive.php?archive=/24/items/wikipedia-scholarly-sources-corpus/10.1201.zip&file=10.1201%252F9781420092592-c27.pdf A proposal for a new classification of Portunoidea and Cancroidea (Brachyura: Heterotremata) based on two independent molecular phylogenies]" in ''Decapod Crustacean Phylogenetics'', 1st edition, published by [[CRC Press]]. {{isbn|9780429145384}} {{SfnRef inline|Schubart|Reuschel|2009}}
*Trewhella, Steve; and Hatcher, Julie, 2021. ''[https://www.google.ca/books/edition/The_Essential_Guide_to_Beachcombing_and/j_YlEAAAQBAJ?hl=en&gbpv=1 The Essential Guide to Beachcombing and the Strandline]'', published by [[Princeton University Press]]. {{isbn|9780691232423}} {{SfnRef inline|Trewhella|Hatcher|2021}}
{{div col end}}
{{sfn whitelist|CITEREFHolthuis1987|CITEREFLinneaus1767|CITEREFAdema1991|CITEREFBarretoBailey2013|CITEREFHaxerliHöpelRichter2022|CITEREFSchubartReuschel2009|CITEREFHazerliHöpelRichter2022|CITEREFHazerliHöpelRichter2022|CITEREFTrewhellaHatcher2021}}

{{Taxonbar|from=Q853487}}

[[Category:Portunoidea]]
[[Category:Crabs of the Atlantic Ocean]]
[[Category:Crustaceans described in 1767]]
[[Category:Taxa named by Carl Linnaeus]]