Editing Jellyfish (section)

== Largest and smallest ==
Jellyfish range from about one millimeter in bell height and diameter,<ref name=MillsHirano /> to nearly {{convert|2|m|ft|frac=2}} in bell height and diameter; the tentacles and mouth parts usually extend beyond this bell dimension.<ref name=Ruppert />

The smallest jellyfish are the peculiar creeping jellyfish in the genera ''[[Staurocladia]]'' and ''[[Eleutheria (hydrozoan)|Eleutheria]]'', which have bell disks from {{convert|0.5|mm|in|frac=32}} to a few millimeters in diameter, with short tentacles that extend out beyond this, which these jellyfish use to move across the surface of seaweed or the bottoms of rocky pools;<ref name=MillsHirano>{{cite book |last=Mills |first=C.E. |author2=Hirano, Y.M. |title=Encyclopedia of Tidepools and Rocky Shores: Hydromedusae |year=2007 |pages=286–288 |isbn=978-0-520-25118-2 |publisher=University of California Press}}</ref> many of these tiny creeping jellyfish cannot be seen in the field without a hand lens or microscope. They can reproduce asexually by [[fission (biology)|fission]] (splitting in half). Other very small jellyfish, which have bells about one millimeter, are the hydromedusae of many species that have just been released from their parent polyps;<ref>{{cite journal |last=Mills |first=C.E. |title=''Podocoryne selena'', a new species of hydroid from the Gulf of Mexico, and a comparison with ''Hydractinia echinata'' |journal=Biological Bulletin |year=1976 |volume=151 |issue=1 |pages=214–224 |doi=10.2307/1540715 |jstor=1540715|url=https://www.biodiversitylibrary.org/part/13948 }}</ref> some of these live only a few minutes before shedding their gametes in the plankton and then dying, while others will grow in the plankton for weeks or months. The hydromedusae ''Cladonema radiatum'' and ''Cladonema californicum'' are also very small, living for months, yet never growing beyond a few mm in bell height and diameter.<ref>{{cite journal |last=Costello |first=J. |title=Laboratory culture and feeding of the hydromedusa ''Cladonema californicum'' Hyman (Anthomedusa: Cladonemidae) |journal=Journal of Experimental Marine Biology and Ecology |year=1988 |volume=123 |issue=2 |pages=177–188 |doi=10.1016/0022-0981(88)90168-2|bibcode=1988JEMBE.123..177C }}</ref>

[[File:Largelionsmanejellyfish.jpg|thumb|upright|The [[lion's mane jellyfish]] (''Cyanea capillata'') is one of the largest species.]]

The [[lion's mane jellyfish]], ''[[Cyanea (jellyfish)|Cyanea]] capillata'', was long-cited as the largest jellyfish, and arguably the longest animal in the world, with fine, thread-like tentacles that may extend up to {{convert|36.5|m|ftin|abbr=on}} long (though most are nowhere near that large).<ref>{{cite web |url=http://www.waterford-today.ie/index.php?option=com_content&task=view&id=933&Itemid=10177&ed=68 |archive-url=https://web.archive.org/web/20100530112100/http://www.waterford-today.ie/index.php?option=com_content&task=view&id=933&Itemid=10177&ed=68 |archive-date=2010-05-30 |title=Rare sighting of a lion's mane jellyfish in Tramore Bay |publisher=Waterford Today |date=1 August 2007 |access-date=18 October 2010}}</ref><ref>{{cite web |url=http://www.redorbit.com/education/reference_library/cnidaria/lions_mane_jellyfish/4326/index.html |title=Lion's Mane Jellyfish – Reference Library |publisher=redOrbit |access-date=18 October 2010 |url-status=live |archive-url=https://web.archive.org/web/20100730012003/http://www.redorbit.com/education/reference_library/cnidaria/lions_mane_jellyfish/4326/index.html |archive-date=30 July 2010|date=2003-06-12 }}</ref> They have a moderately painful, but rarely fatal, sting.<ref>{{cite web |url=http://www.wmur.com/news/24341753/detail.html |title=150 Stung By Jellyfish At Rye Beach |publisher=Wmur.com |date=21 July 2010 |access-date=11 June 2018 |url-status=dead |archive-url=https://web.archive.org/web/20111014004929/http://www.wmur.com/news/24341753/detail.html |archive-date=14 October 2011}}</ref>
The increasingly common giant [[Nomura's jellyfish]], ''[[Nemopilema nomurai]]'', found in some, but not all years in the waters of [[Japan]], [[Korea]] and [[China]] in summer and autumn is another candidate for "largest jellyfish", in terms of diameter and weight, since the largest Nomura's jellyfish in late autumn can reach {{convert|2|m|ftin|abbr=on}} in bell (body) diameter and about {{convert|200|kg|lb|abbr=on}} in weight, with average specimens frequently reaching {{convert|0.9|m|ftin|abbr=on|0}} in bell diameter and about {{convert|150|kg|abbr=on}} in weight.<ref>{{cite journal |last=Omori |first=Makoto |author2=Kitamura, Minoru |title=Taxonomic review of three Japanese species of edible jellyfish (Scyphozoa: Rhizostomeae) |journal=Plankton Biology and Ecology |year=2004 |volume=51 |issue=1 |pages=36–51 |url=http://www.plankton.jp/PBE/issue/vol51_1/vol51_1_036.pdf |url-status=live |archive-url=https://web.archive.org/web/20120323235428/http://www.plankton.jp/PBE/issue/vol51_1/vol51_1_036.pdf |archive-date=23 March 2012}}</ref><ref>{{cite journal |last=Uye |first=Shin-Ichi |title=Blooms of the giant jellyfish ''Nemopilema nomurai'': a threat to the fisheries sustainability of the East Asian Marginal Seas |url=http://www.plankton.jp/PBR/issue/vol03_suppl/03suppl_125.pdf |journal=Plankton & Benthos Research |year=2008 |volume=3 (Supplement) |pages=125–131 |doi=10.3800/pbr.3.125 |url-status=live |archive-url=https://web.archive.org/web/20130516154258/http://www.plankton.jp/PBR/issue/vol03_suppl/03suppl_125.pdf |archive-date=16 May 2013|doi-access=free }}</ref> The large bell mass of the giant Nomura's jellyfish<ref>{{cite news |title=Giant Echizen jellyfish off Japan coast |url=http://news.bbc.co.uk/2/hi/science/nature/8385953.stm |publisher=BBC |date=30 November 2009 |url-status=live |archive-url=https://web.archive.org/web/20110101105524/http://news.bbc.co.uk/2/hi/science/nature/8385953.stm |archive-date=1 January 2011}}</ref> can dwarf a diver and is nearly always much greater than the Lion's Mane, whose bell diameter can reach {{convert|1|m|ftin|abbr=on}}.<ref>{{cite journal |last=Kramp |first=P.L. |title=Synopsis of the medusae of the world |journal=[[Journal of the Marine Biological Association of the United Kingdom]] |year=1961 |volume=40 |pages=1–469 |doi=10.1017/s0025315400007347|doi-broken-date=1 November 2024 |bibcode=1961JMBUK..40....7K }}</ref>

The rarely encountered deep-sea jellyfish ''[[Stygiomedusa gigantea]]'' is another candidate for "largest jellyfish", with its thick, massive bell up to {{convert|100|cm|ftin|abbr=on}} wide, and four thick, "strap-like" oral arms extending up to {{convert|6|m|ft|frac=2|abbr=on}} in length, very different from the typical fine, threadlike tentacles that rim the umbrella of more-typical-looking jellyfish, including the Lion's Mane.<ref>{{cite news |title=Giant deep sea jellyfish filmed in Gulf of Mexico |url=http://news.bbc.co.uk/earth/hi/earth_news/newsid_8638000/8638527.stm |work=BBC Earth News |date=23 April 2010 |first=Jody |last=Bourton |url-status=live |archive-url=https://web.archive.org/web/20100705082759/http://news.bbc.co.uk/earth/hi/earth_news/newsid_8638000/8638527.stm |archive-date=5 July 2010}}</ref>

[[Desmonema (cnidarian)|''Desmonema glaciale'']], which lives in the Antarctic region, can reach a very large size (several meters).<ref>{{cite web | url=https://www.inaturalist.org/taxa/780667-Desmonema-glaciale/browse_photos | title=Photos of Antarctic Giant Jelly (Desmonema glaciale) {{*}} iNaturalist }}</ref><ref>{{Cite journal |last=League |first=Michael |date=11 October 2011 |title=The Way to End a Dive |url=https://www.polartrec.com/expeditions/adaptations-of-marine-worms-in-antarctica/journals/2011-10-11 |journal=[[PolarTREC]] |location=[[McMurdo Station]], Antarctica |access-date=13 June 2023 |archive-date=13 June 2023 |archive-url=https://web.archive.org/web/20230613094135/https://www.polartrec.com/expeditions/adaptations-of-marine-worms-in-antarctica/journals/2011-10-11 |url-status=dead }}</ref> [[Chrysaora colorata|Purple-striped jelly]] (''Chrysaora colorata'') can also be extremely long (up to 15 feet).<ref>{{cite web | url=https://www.uwphotographyguide.com/purple-jellyfish-underwater | title=Diving underwater with giant jellyfish | date=26 April 2010 }}</ref>