Helice tridens
{{Short description|Species of crab}}
{{Speciesbox
| image = Helice tridens (Kohnoura).jpg
| genus = Helice
| species = tridens
| authority = (De Haan, 1835) {{cite web |url=http://www.marinespecies.eu/species.php?species_group=crabs_of_japan&menuentry=soorten&id=1739&tab=beschrijving |title=Helice tridens |work=Crabs of Japan |accessdate=January 31, 2009}}
| synonyms_ref = {{cite journal|journal=Raffles Bulletin of Zoology |year=2008 |volume=17 |pages=1–286 |title=Systema Brachyurorum: Part I. An annotated checklist of extant Brachyuran crabs of the world |author=P. K. L. Ng, D. Guinot & P. J. F. Davie |url=http://rmbr.nus.edu.sg/rbz/biblio/s17/s17rbz.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20110606061453/http://rmbr.nus.edu.sg/rbz/biblio/s17/s17rbz.pdf |archivedate=2011-06-06 }}
| synonyms =
- Ocypode tridens De Haan, 1835
- Cyclograpsus latreillii H. Milne-Edwards, 1837
- Helice latreillei H. Milne-Edwards, 1837
}}
Helice tridens is a species of crab which lives on mudflats around the coasts of Japan and the Korean Peninsula.{{cite journal |journal=Zoological Studies |url=http://zoolstud.sinica.edu.tw/Journals/47.1/114.pdf |title=Taxonomy, phylogeny, and biogeography of the endemic mudflat crab Helice/Chasmagnathus complex (Crustacea: Brachyura: Varunidae) from East Asia |author1=Hsi-Te Shih |author2=Hiroshi Suzuki |name-list-style=amp |volume=47 |issue=1 |pages=114–125 |year=2008 |access-date=2010-03-27 |archive-date=2017-08-09 |archive-url=https://web.archive.org/web/20170809075913/http://zoolstud.sinica.edu.tw/Journals/47.1/114.pdf |url-status=dead }}
Ecology
It is semi-terrestrial, returning to the sea to spawn.{{cite book |chapter=Rapid range expansion of the feral raccoon (Procyon lotor) in Kanagawa Prefecture, Japan, and its impact on native organisms |author1=Hisayo Hayama, Masato Kaneda |author2=Mayuh Tabata |name-list-style=amp |pages=196–199 |editor1=F. Koike |editor2=M. N. Clout |editor3=M. Kawamichi |editor4=M. De Poorter |editor5=K. Iwatsuki |title=Assessment and Control of Biological Invasion Risks |publisher=Shoukadoh Book Sellers, Kyoto, Japan and IUCN, Gland, Switzerland |year=2006 |url=http://vege1.kan.ynu.ac.jp/isp/pdf/Hayama_et_al.pdf |access-date=2009-01-31 |archive-url=https://web.archive.org/web/20110722080721/http://vege1.kan.ynu.ac.jp/isp/pdf/Hayama_et_al.pdf |archive-date=2011-07-22 |url-status=dead }} The species appears to be adversely affected by the presence of raccoons (Procyon lotor), an invasive predator. H. tridens has a salinity requirement which lies between those of two other estuarine crabs in Japan, Helicana japonica and Chiromantes dehaani.{{cite journal |journal=Tohoku Journal of Agricultural Research |volume=44 |issue=1–4 |year=1994 |title=Difference of salinity requirements among the three estuarine crab species, Chiromantes dehaani, Helice tridens and H. japonica (Brachyura: Grapsidae) |author1=Bambang Irawan |author2=Akihiro Kijima |name-list-style=amp |url=http://ir.library.tohoku.ac.jp/re/bitstream/10097/29948/1/KJ00000715049.pdf |access-date=2009-01-31 |archive-url=https://web.archive.org/web/20120602075333/http://ir.library.tohoku.ac.jp/re/bitstream/10097/29948/1/KJ00000715049.pdf |archive-date=2012-06-02 |url-status=dead }}
Smaller individuals shelter in burrows in reed marshes, apparently in order to avoid cannibalism; this may also be the reason for the migration of larger individuals to brackish water lagoons in summer, when the crabs exceed their carrying capacity.{{cite journal |title=Wandering behaviour of the mud-crab Helice tridens related to evasion of cannibalism |author1=Yasushi Kurihara, Katsuhiro Sekimoto |author2=Masahide Miyata |name-list-style=amp |url=https://www.int-res.com/articles/meps/49/m049p041.pdf |volume=49 |pages=41–50 |year=1988 |journal=Marine Ecology Progress Series |doi=10.3354/meps049041|doi-access=free |bibcode=1988MEPS...49...41K }}
Taxonomy
Helice tridens was first described by Wilhem de Haan in an 1835 volume of Fauna Japonica, as Ocypode tridens.{{cite book |chapter-url=http://edb.kulib.kyoto-u.ac.jp/exhibit/b04/image/01/b04s0137.html |title=Fauna Japonica |author=Wilhem de Haan |author-link=Wilhem de Haan |editor=Philipp Franz von Siebold |editor-link=Philipp Franz von Siebold |year=1835 |chapter=Ocypode (Helice) tridens sp. nov. |page=57 |access-date=2009-01-31 |archive-date=2011-07-25 |archive-url=https://web.archive.org/web/20110725014805/http://edb.kulib.kyoto-u.ac.jp/exhibit/b04/image/01/b04s0137.html |url-status=dead }} The former subspecies H. t. wuana and H. t. sheni are now recognised as a separate species, Helicana wuana.
References
{{Reflist|32em}}
External links
{{Portal|Crustaceans}}
- {{Commons category-inline|Helice tridens|Helice tridens}}
{{Taxonbar|from=Q5704964}}
Category:Crustaceans described in 1835