View source for Cirrina

{{Short description|Suborder of octopuses}}
{{Automatic taxobox
| fossil_range = {{fossil range|Campanian|present}}
| image = Cirrothauma murrayi2.jpg
| image_caption = Oral view of ''[[Cirrothauma murrayi]]'' showing single row of suckers and paired cirri
| taxon = Cirrina
| subdivision_ranks = Families
| subdivision = [[Opisthoteuthidae]]<br />[[Grimpoteuthidae]]<br />[[Cirroteuthidae]]<br />[[Stauroteuthis|Stauroteuthidae]]<br />[[Cirroctopus|Cirroctopodidae]]
| synonyms = *Cirrata<br /><small>Grimpe, 1916</small>
*Cirroctopoda<br /><small>Young, 1989</small>
| authority = [[Grimpe]], 1916 ''sensu'' [[Felley]] ''et al.'', 2001
}}
'''Cirrina''' or '''Cirrata''' is a suborder and one of the two main divisions of [[octopus]]es. Cirrate octopuses have a [[Cirrate shell|small, internal shell]] and [[Cephalopod fin|two fins]] on their head, while their sister suborder [[Incirrina]] has neither. The fins of cirrate octopods are associated with a unique cartilage-like shell in a shell sac. In cross-section, the fins have distinct proximal and distal regions, both of which are covered by a thin surface sheath of muscle.
The suborder is named for small, [[cilia]]-like strands (cirri) on the arms of the octopus, a pair for each sucker.  These are thought to play some role in feeding, perhaps by creating currents of water that help bring food closer to the beak. Cirrate octopuses are noteworthy for lacking [[ink]] sacs.
The oldest known member of the group is ''[[Paleocirroteuthis]]'' from the [[Late Cretaceous]] of Japan and Canada.<ref>{{Cite journal |last1=Tanabe |first1=Kazushige |last2=Trask |first2=Pat |last3=Ross |first3=Rick |last4=Hikida |first4=Yoshinori |date=2008 |title=Late Cretaceous octobrachiate coleoid lower jaws from the north Pacific regions |url=https://www.cambridge.org/core/journals/journal-of-paleontology/article/abs/late-cretaceous-octobrachiate-coleoid-lower-jaws-from-the-north-pacific-regions/4ABDF56B2029DF258947C90FA1632A5B |journal=Journal of Paleontology |language=en |volume=82 |issue=2 |pages=398–408 |doi=10.1666/07-029.1 |issn=0022-3360}}</ref>
==Phylogeny==
A [[molecular phylogeny]] based on [[mitochondria]]l and [[nuclear DNA]] marker sequences by
Sanchez ''et al.'', 2018, shows that the Cirrina is [[paraphyletic]], i.e. it is not a single [[clade]]. Instead, a clade containing [[Opisthoteuthidae]] and [[Cirroctopodidae]] is sister to the Octopodida, while a clade containing [[Cirroteuthidae]] and [[Stauroteuthidae]] is sister to the clade that contains those other groups.<ref name="Sanchez et al, 2018">{{cite journal | last1=Sanchez | first1=Gustavo | last2=Setiamarga | first2=Davin H. E. | last3=Tuanapaya | first3=Surangkana | last4=Tongtherm | first4=Kittichai | last5=Winkelmann | first5=Inger E. | last6=Schmidbaur | first6=Hannah | last7=Umino | first7=Tetsuya | last8=Albertin | first8=Caroline | last9=Allcock | first9=Louise | last10=Perales-Raya | first10=Catalina | last11=Gleadall | first11=Ian | last12=Strugnell | first12=Jan M. | last13=Simakov | first13=Oleg | last14=Nabhitabhata | first14=Jaruwat | title=Genus-level phylogeny of cephalopods using molecular markers: current status and problematic areas | journal=PeerJ  | volume=6 | year= 2018 | doi=10.7717/peerj.4331 | pmid=29456885 | pmc=5813590 | page=e4331 | doi-access=free }}</ref> However, subsequent studies, using a greater coverage of species and genes, have found Cirrata and [[Incirrata]] to be monophyletic clades,<ref name=":0">{{Cite journal |last1=Taite |first1=M. |last2=Fernández-Álvarez |first2=F. Á. |last3=Braid |first3=H. E. |last4=Bush |first4=S. L. |last5=Bolstad |first5=K. |last6=Drewery |first6=J. |last7=Mills |first7=S. |last8=Strugnell |first8=J. M. |last9=Vecchione |first9=M. |last10=Villanueva |first10=R. |last11=Voight |first11=J. R. |last12=Allcock |first12=A. L. |date=2023-02-10 |title=Genome skimming elucidates the evolutionary history of OctopodA |url=https://www.sciencedirect.com/science/article/pii/S1055790323000295 |journal=Molecular Phylogenetics and Evolution |volume=182 |language=en |pages=107729 |doi=10.1016/j.ympev.2023.107729 |pmid=36773750 |s2cid=256804597 |issn=1055-7903|hdl=10261/329953 |hdl-access=free }}</ref> consistent with earlier morphological and molecular studies.<ref name=":1">{{Cite journal |last1=Piertney |first1=Stuart B. |last2=Hudelot |first2=Cendrine |last3=Hochberg |first3=F. G. |last4=Collins |first4=Martin A. |date=2003-05-01 |title=Phylogenetic relationships among cirrate octopods (Mollusca: Cephalopoda) resolved using mitochondrial 16S ribosomal DNA sequences |url=https://www.sciencedirect.com/science/article/pii/S1055790302004207 |journal=Molecular Phylogenetics and Evolution |language=en |volume=27 |issue=2 |pages=348–353 |doi=10.1016/S1055-7903(02)00420-7 |pmid=12695097 |issn=1055-7903}}</ref><ref>{{Cite journal |last1=Lindgren |first1=Annie R. |last2=Pankey |first2=Molly S. |last3=Hochberg |first3=Frederick G. |last4=Oakley |first4=Todd H. |date=2012-07-28 |title=A multi-gene phylogeny of Cephalopoda supports convergent morphological evolution in association with multiple habitat shifts in the marine environment |journal=BMC Evolutionary Biology |volume=12 |issue=1 |pages=129 |doi=10.1186/1471-2148-12-129 |issn=1471-2148 |pmc=3733422 |pmid=22839506 |doi-access=free }}</ref>
==Classification==
The family level clades recognized within Cirrina has changed over time. Currently five families are recognized by the [[World Register of Marine Species]] allocated to two superfamily level clades, Superfamily Cirroteuthoidea ([[Cirroteuthidae]], [[Stauroteuthidae]]) and Superfamily Opisthoteuthoidea ([[Umbrella octopus|Opisthoteuthidae]], [[Grimpoteuthidae]], and [[Cirroctopodidae]]),<ref>{{Cite web |title=WoRMS - World Register of Marine Species - Cirrata |url=https://www.marinespecies.org/aphia.php?p=taxdetails&id=11732 |access-date=2023-06-24 |website=www.marinespecies.org}}</ref> with these groups also recognized in recent molecular work.<ref name=":0" /><ref>{{Cite journal |last=Verhoeff |first=Tristan Joseph |date=2023-11-24 |title=The molecular phylogeny of cirrate octopods (Cephalopoda: Octopoda: Cirrata) using COI and 16S sequences |url=https://www.foliamalacologica.com/The-molecular-phylogeny-of-cirrate-octopods-Cephalopoda-Octopoda-Cirrata-using-COI,175806,0,2.html |journal=Folia Malacologica |language=english |volume=31 |issue=4 |pages=175–196 |doi=10.12657/folmal.031.026 |issn=1506-7629}}</ref> The families Cirroteuthidae and Stauroteuthidae have been problematic, while they are distinct morphologically, molecular studies using mitochondrial genes revealed a single family (Stauroteuthidae being synonymized under Cirroteuthidae),<ref name=":1" /> but more recent analysis using nuclear genes does show separation.<ref name=":0" /> The family [[Grimpoteuthidae]] has also at times been synonymized under [[Umbrella octopus|Opisthoteuthidae]] but is currently well supported.<ref name=":1" /><ref>{{Cite book |url=http://www.crcnetbase.com/doi/book/10.1201/9781420006391 |title=Oceanography and Marine Biology: An Annual Review, Volume 44 |date=2006-06-13 |publisher=CRC Press |isbn=978-0-8493-7044-1 |editor-last=Gibson |editor-first=R |series=Oceanography and Marine Biology - An Annual Review |language=en |doi=10.1201/9781420006391 |editor-last2=Atkinson |editor-first2=R |editor-last3=Gordon |editor-first3=J}}</ref><ref name=":0" /><ref>{{Cite journal |last1=Verhoeff |first1=Tristan Joseph |last2=O’Shea |first2=Steve |date=2022-01-02 |title=New records and two new species of Grimpoteuthis (Octopoda: Cirrata: Grimpoteuthididae) from southern Australia and New Zealand |url=https://www.tandfonline.com/doi/full/10.1080/13235818.2022.2035889 |journal=Molluscan Research |language=en |volume=42 |issue=1 |pages=4–30 |doi=10.1080/13235818.2022.2035889 |s2cid=247020706 |issn=1323-5818}}</ref><ref>{{Cite journal |last1=Ziegler |first1=Alexander |last2=Sagorny |first2=Christina |date=2021-04-23 |title=Holistic description of new deep sea megafauna (Cephalopoda: Cirrata) using a minimally invasive approach |journal=BMC Biology |volume=19 |issue=1 |pages=81 |doi=10.1186/s12915-021-01000-9 |issn=1741-7007 |pmc=8063452 |pmid=33888110 |doi-access=free }}</ref>
*CLASS [[Cephalopoda|CEPHALOPODA]]
**Subclass [[Nautiloidea]]: nautilus
**Subclass †[[Ammonoidea]]: ammonites
**Subclass [[Coleoidea]]
***Superorder [[Decapodiformes]]: [[squid]], [[cuttlefish]]
***Superorder [[Octopodiformes]]
****Family †[[Trachyteuthididae]] <small>(''[[incertae sedis]]'')</small>
****Order [[Vampyromorphida]]: vampire squid
****Order [[Octopoda]]
*****Genus †''[[Keuppia]]'' <small>(''[[incertae sedis]]'')</small>
*****Genus †''[[Palaeoctopus]]'' <small>(''[[incertae sedis]]'')</small>
*****Genus †''[[Proteroctopus]]'' <small>(''[[incertae sedis]]'')</small>
*****Genus †''[[Styletoctopus]]'' <small>(''[[incertae sedis]]'')</small>
*****Suborder '''Cirrina''': finned deep-sea octopus
******Superfamily Opisthoteuthoidea
*******Family [[Opisthoteuthidae]] (containing ''[[Opisthoteuthis]], [[Exsuperoteuthis]] & [[Insigniteuthis]]'')
*******Family [[Grimpoteuthidae]] (containing ''[[Grimpoteuthis]]'', ''[[Cryptoteuthis]]'', & ''[[Luteuthis]]'')
*******Family [[Cirroctopus|Cirroctopodidae]] (containing ''[[Cirroctopus]]'')
******Superfamily Cirroteuthoidea
******* Family [[Cirroteuthidae]] (containing ''[[Cirroteuthis]]'' & ''[[Cirrothauma]]'')
******* Family [[Stauroteuthis|Stauroteuthidae]] (containing ''[[Stauroteuthis]]'')
****** Family & Superfamily uncertain: †''[[Paleocirroteuthis]]''<ref>{{Cite journal |last1=Tanabe |first1=Kazushige |last2=Trask |first2=Pat |last3=Ross |first3=Rick |last4=Hikida |first4=Yoshinori |date=March 2008 |title=Late Cretaceous octobrachiate coleoid lower jaws from the north Pacific regions |url=https://www.cambridge.org/core/journals/journal-of-paleontology/article/abs/late-cretaceous-octobrachiate-coleoid-lower-jaws-from-the-north-pacific-regions/4ABDF56B2029DF258947C90FA1632A5B |journal=Journal of Paleontology |language=en |volume=82 |issue=2 |pages=398–408 |doi=10.1666/07-029.1 |bibcode=2008JPal...82..398T |s2cid=130635916 |issn=0022-3360}}</ref>
*****Suborder [[Incirrina]]: octopus without mantle fins or cirri.
==References==
{{Reflist}}
==External links==
*[http://tolweb.org/Cirrata/20086 Cirrata] at the [[Tree of Life Web Project]]
*[http://tolweb.org/notes/?note_id=1486 Cirrate male reproductive tract] at the [[Tree of Life Web Project]]
{{Taxonbar|from=Q2289096}}
[[Category:Octopuses]]
{{octopus-stub}}
[[Category:Extant Campanian first appearances]]