Editing Nautilus (section)

{{Short description|Family of molluscs}}
{{About|the marine mollusc family Nautilidae|ships of the same name|List of ships named Nautilus|other uses}}
{{Automatic taxobox
| name = Nautilus
| fossil_range = [[Triassic]]{{en dash}}present {{Fossil range|230|0|ref=<ref>{{Cite journal| journal = Journal of Paleontology| year = 1997| volume = 71| issue = 6| title = ''Allonautilus'': A New Genus of Living Nautiloid Cephalopod and Its Bearing on Phylogeny of the Nautilida| last1 = Ward| first1 = P. D.| last2 = Saunders| first2 = W. B.| jstor = 1306604| pages = 1054–1064| doi = 10.1017/S0022336000036039| bibcode = 1997JPal...71.1054W| s2cid = 87319305}}</ref>}}
| image = Nautilus belauensis from Palau.jpg
| image_caption = ''[[Palau Nautilus|Nautilus belauensis]]''
| status = CITES_A2
| status_system = CITES
| taxon = Nautilidae
| authority = [[Henri Marie Ducrotay de Blainville|Blainville]], 1825
| subdivision_ranks = Genera
| subdivision = †''[[Carinonautilus]]''<br/>
†''[[Cenoceras]]''<br/>
†''[[Eutrephoceras]]''<br/>
†''[[Pseudocenoceras]]''<br/>
†''[[Strionautilus]]''<br/>
''[[Allonautilus]]''<br/>
''[[Nautilus (genus)|Nautilus]]''<br/>
† = Extinct
| synonyms_ref = <ref>{{cite journal |last1=Cichowolski|first1=M. |last2=Ambrosio|first2=A. |last3=Concheyro|first3=A. |doi=10.1017/S0954102005002671 |title=Nautilids from the Upper Cretaceous of the James Ross Basin, Antarctic Peninsula |journal=[[Antarctic Science]] |volume=17 |issue=2 |page=267 |year=2005 |bibcode=2005AntSc..17..267C |s2cid=128767860 |hdl=11336/96152 |hdl-access=free }}</ref>
| synonyms = *Eutrephoceratidae <small>Miller, 1951</small>
}}

A '''nautilus''' ({{etymology|la|{{wikt-lang|la|nautilus}}|sails like a vessel}}; {{etymology|grc|''{{wikt-lang|grc|ναυτίλος}}'' ({{grc-transl|ναυτίλος}})|seaman, sailor }})<ref>{{cite encyclopedia |url= https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0059%3Aentry%3Dnautilus |title= nautĭlus or nautĭlŏs |last1= Lewis |first1= Charlton T. |author1-link=Charlton T. Lewis |last2= Short |first2= Charles|author2-link=Charles Short |dictionary= A Latin Dictionary |edition= |publisher= [[Perseus Digital Library]] |date = 1879 }}</ref> {{efn|The word originally referred to a type of [[Mediterranean]]<ref name=Prescott>{{Cite journal|last1= Prescott|first1=Henry W.|author1-link=Henry W. Prescott |url=https://www.jstor.org/stable/262901  |date=October 1921|title=Callimachus' Epigram on the Nautilus|journal=[[Classical Philology (journal)|Classical Philology]]|volume=16|issue=4|publisher=[[University of Chicago Press]]|doi=|issn=|arxiv=|bibcode=|s2cid=|doi-access=}}</ref> [[cephalopod]] [[mollusc]] ''[[Argonauta argo#Gallery|Argonauta argo]]'', also known as 'paper nautilus', which were thought to use their membrane arms as sails.<ref>{{cite web|url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dnauti/los |title=ναυτίλος |last1=Liddell |first1=Henry George |last2=Scott |first2=Robert |work=A Greek-English Lexicon |publisher=Perseus Digital Library |date= 1940 }}</ref> [[Ancient Greek]] usage: [[Aristotle]]. [[Callimachus]] - [[Callimachus#Epigrams|Epigram]]<ref name=Prescott/> V.<ref>{{cite web|url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0226%3Atext%3Depigrams%3Apoem%3D5|website=www.perseus.tufts.edu|title=Callimachus, Epigrams|date=|editor=Ulrich von Wilamowitz-Moellendorff|editor-link=Ulrich von Wilamowitz-Moellendorff|publisher=|access-date=|url-status=|archive-url=|archive-date=}}</ref>}} is any of the various species within the [[cephalopod]] family '''Nautilidae'''. This is the sole extant family of the superfamily [[Nautilaceae]] and the suborder [[Nautilina]].

It comprises nine living species in two genera, the [[type genus|type]] of which is the genus ''[[Nautilus (genus)|Nautilus]]''. Though it more specifically refers to the species ''[[chambered nautilus|Nautilus pompilius]]'', the name [[chambered nautilus]] is also used for any of the Nautilidae. All are protected under [[CITES]] [[CITES Appendix II|Appendix II]].<ref>{{cite web |title=Checklist of CITES species |url=http://checklist.cites.org |publisher=[[CITES]] |access-date=24 June 2020}} (please fill in 'Nautilus' in the search-box).</ref> Depending on species, adult shell diameter is between {{convert|4|and|10|in|cm|abbr=in|order=flip}}.

The Nautilidae, both extant and extinct, are characterized by [[involute]] or more or less convoluted shells that are generally smooth, with compressed or depressed [[whorl (mollusc)|whorl]] sections, straight to sinuous [[Suture (anatomy)|suture]]s, and a tubular, generally central [[siphuncle]].<ref name=Kummel>Kümmel, B. 1964. Nautiloidae-Nautilida, in the [[Treatise on Invertebrate Paleontology]], Geological Society of America and Univ of Kansas Press, Teichert and Moore eds.</ref> Having survived relatively unchanged for hundreds of millions of years, nautiluses represent the only living members of the subclass [[Nautiloidea]], and are often considered "[[living fossil]]s".
[[File:The_first_and_oldest_fossil_of_Chambered_Nautilus_displayed_at_Philippine_National_Museum.jpg|thumb|The first and oldest fossil of [[chambered nautilus]] displayed at [[National Museum of the Philippines|Philippine National Museum]].]]