Cirrothauma
{{Short description|Genus of octopuses}}
{{Automatic taxobox
| image = CirrothaumaMurDraw2.jpg
| image_caption = Cirrothauma murrayi
| taxon = Cirrothauma
| authority = Chun, 1911{{cite web | url = http://www.marinespecies.org/aphia.php?p=taxdetails&id=137791 | title = Cirrothauma Chun, 1911 | accessdate = 3 March 2018 | publisher = Flanders Marine Institute | author = Julian Finn| year = 2016 | work = World Register of Marine Species}}
| type_species = Cirrothauma murrayi
| type_species_authority = Chun, 1911
}}
Cirrothauma is a genus of deep water octopuses from the cirrate family Cirroteuthidae. The species of Cirrothauma are fragile, gelatinous deep-sea octopods with a large 'butterfly-shaped' shell.
They are unique in the Octopoda in being blind, with eyes lacking lenes and being imbedded/covered in head tissues. The genus contains a single species Cirrothauma murrayi.{{Cite journal |last=Verhoeff |first=Tristan Joseph |last2=O'Shea |first2=Steve |date=2025-03-14 |title=A new southern hemisphere species of Cirroteuthis (Octopoda: Cirrata: Cirroteuthidae), and re-evaluation of the taxonomic status of Cirroteuthis hoylei Robson, 1932 |url=https://www.foliamalacologica.com/A-new-southern-hemisphere-species-of-Cirroteuthis-Octopoda-Cirrata-Cirroteuthidae,199484,0,2.html |journal=Folia Malacologica |language=english |issue=1 |doi=10.12657/folmal.033.003 |issn=1506-7629|doi-access=free }}{{Cite web |title=WoRMS - World Register of Marine Species - Cirrothauma Chun, 1911 |url=https://www.marinespecies.org/aphia.php?p=taxdetails&id=137791 |access-date=2025-03-21 |website=www.marinespecies.org}}
Species and taxonomy
Two other species have formerly been included in Cirrothauma,{{cite web | url = http://tolweb.org/Cirrothauma/20095 | title = Cirrothauma Chun 1911 | accessdate = 3 March 2018 | publisher = Tree of Life Web Project | author1 = Richard E. Young | author2 = Michael Vecchione | year = 2012}} but have recently been allocated to their own genus (Inopinoteuthis): Inopinoteuthis magna (Hoyle, 1885) and Inopinoteuthis hoylei (Robson, 1932).{{Cite web |title=WoRMS - World Register of Marine Species - Inopinoteuthis Verhoeff & O'Shea, 2025 |url=https://www.marinespecies.org/aphia.php?p=taxdetails&id=1804323 |access-date=2025-03-21 |website=www.marinespecies.org |language=en}}
Both Cirrothauma and Inopinoteuthis have butterfly-shaped shells, and much longer arms than the related Cirroteuthis. Genera Cirrothauma and Inopinoteuthis can be separated given the presence of well-developed eyes on Inopinoteuthis (vs. vestigial eyes) as well as the presence of functional suckers with suction chambers on Inopinoteuthis (Cirrothauma have minute vestigial suckers atop elongate fleshy stalks across the mid-distal arm regions).
Range
The single recognized species Cirrothauma murrayi has been reported from various locations across the Atlantic, Arctic, and Pacific Oceans, but seemingly not the Southern Ocean.{{Cite journal |last=Aldred |first=R. G. |last2=Nixon |first2=Marion |last3=Young |first3=John Zachary |date=1983 |title=Cirrothauma murrayi chun, a finned octopod |url=https://royalsocietypublishing.org/doi/10.1098/rstb.1983.0021 |journal=Philosophical Transactions of the Royal Society of London. B, Biological Sciences |volume=301 |issue=1103 |pages=1–54 |doi=10.1098/rstb.1983.0021|url-access=subscription }}{{cite book | url = http://www.fao.org/3/a-i3489e.pdf | title = Cephalopds of the World An Annotated and illustrated catalogue of Cephalopods species known to date Volume 3 Octopods and Vampire Squids | editor1 = Patrizia Jereb | editor2 = Clyde F.E. Roper | editor3 = Mark D. Norman | editor4 = Julian K. Finn | year = 2016 | publisher = Food and Agriculture Organisation of the United Nations, Rome |isbn = 9789251079898 | page = 250}}
Species
There is a single currently recognized species within the genus Cirrothauma, though a second (as yet undescribed taxon) is indicated in molecular data.
- Cirrothauma murrayi Chun, 1911