Editing Coelacanth

{{Short description|Class of lobe-finned fishes}}
{{About|the class of fish|the living species of coelacanths|Latimeria}}
{{Use dmy dates|date=February 2025}}
{{Automatic taxobox
| name = Coelacanths
| fossil_range = [[Early Devonian]] – [[Recent]],<ref name="ref4" /> {{fossil range|409|0}}
| image = Coelacanth off Pumula on the KwaZulu-Natal South Coast, South Africa, on 22 November 2019.png
| image_caption = Live coelacanth seen off [[Umzumbe|Pumula]] on the [[KwaZulu-Natal South Coast]], South Africa, 2019
| image_upright = 1.15
| image2 = Axelrodichthys araripensis - Naturmuseum Senckenberg - DSC02202.JPG
| image2_caption = Specimen of ''[[Axelrodichthys]] araripensis'' from the Early Cretaceous of Brazil ([[Mawsoniidae]])
| display_parents = 2
| taxon = Actinistia
| authority = [[Edward Drinker Cope|Cope]], 1871
| type_species = {{extinct}}''[[Coelacanthus granulatus]]''
| type_species_authority = [[Louis Agassiz|Agassiz]], 1839
| subdivision_ranks = [[Family (biology)|Families]]
| subdivision = *'''Coelacanthiformes'''
**'''Latimerioidei'''
***[[Latimeriidae]]
***{{extinct}}[[Mawsoniidae]]
And see [[#Evolution and taxonomy|text]]
}}

'''Coelacanths''' ({{IPAc-en|audio=En-us-coelacanth.ogg|ˈ|s|iː|l|ə|k|æ|n|θ}} {{respell|SEE|lə-kanth}}) are an ancient group of [[Sarcopterygii|lobe-finned fish]] (Sarcopterygii) in the [[Class (biology)|class]] '''Actinistia'''.<ref>{{Cite book |last=Nelson |first=Joseph S. |url=http://worldcat.org/oclc/951128215 |title=Fishes of the World |date=16 March 2016 |publisher=John Wiley & Sons |isbn=978-1-119-22081-7 |oclc=951128215|pages=103-105}}</ref><ref>{{Cite web |title=Order Summary for Coelacanthiformes |url=https://www.fishbase.se/summary/OrdersSummary.php?order=Coelacanthiformes |access-date=2023-03-13 |website=fishbase.se}}</ref> As sarcopterygians, they are more closely related to [[lungfish]] and [[tetrapods]] (which includes [[amphibian]]s, [[reptile]]s, [[bird]]s and [[mammal]]s) than to [[Actinopterygii|ray-finned fish]].

Well-represented in both freshwater and marine fossils since the [[Devonian]], they are now represented by only two [[Extant taxon|extant]] marine [[species]] in the genus ''[[Latimeria]]'': the [[West Indian Ocean coelacanth]] (''Latimeria chalumnae''), primarily found near the [[Comoro Islands]] off the east coast of Africa, and the [[Indonesian coelacanth]] (''Latimeria menadoensis'').<ref>{{Cite journal|title = Adaptive evolution of color vision of the Comoran coelacanth (Latimeria chalumnae)|journal = Proceedings of the National Academy of Sciences|volume = 96|issue = 11|pages = 6279–84|last1 = Yokoyama|first1 = Shozo|last2 = Zhang|first2 = Huan|last3 = Radlwimmer|first3 = F. Bernhard|last4 = Blow|first4 = Nathan S.|year = 1999|doi = 10.1073/pnas.96.11.6279|pmid = 10339578|pmc = 26872|bibcode = 1999PNAS...96.6279Y|doi-access = free}}</ref> The name ''coelacanth'' originates from the [[Permian]] genus ''[[Coelacanthus]]'', which was the first [[scientifically named]] coelacanth.<ref>{{cite book|last=Agassiz|first=L.|author-link=Louis Agassiz|date=1839|title= Recherches sur les poissons fossiles II|url=https://www.biodiversitylibrary.org/bibliography/4275|publisher=Petitpierre|location=Neuchâtel|doi=10.5962/bhl.title.4275|pages=xxxvi-xxxviii|access-date=12 May 2025}}</ref><ref>{{cite web|url=https://www.nhm.ac.uk/discover/coelacanths-the-fish-that-outdid-the-loch-ness-monster.html|title=Coelacanths: the fish that 'outdid' the Loch Ness Monster |last=Osterloff|first=Emily|publisher=Natural History Museum, London|access-date=12 May 2025}}</ref>

The oldest known coelacanth fossils date back more than 410{{nbsp}}million years. Coelacanths were thought to have become extinct in the [[Late Cretaceous]], around 66{{nbsp}}million years ago, but were discovered living off the coast of [[South Africa]] in 1938.<ref name=Smith>{{cite book|last=Smith|first=J. L. B.|title=Old Fourlegs: the Story of the Coelacanth|publisher=Longmans Green |year=1956 |page=24}}</ref><ref name="ref2">{{cite journal |bibcode=1975Sci...190.1105L |title=Latimeria, the Living Coelacanth, is Ovoviviparous |last1=Lavett Smith |first1=C. |last2=Rand |first2=Charles S. |last3=Schaeffer |first3=Bobb |last4=Atz |first4=James W. |volume=190 |year=1975 |pages=1105–6 |journal=Science |doi=10.1126/science.190.4219.1105 |issue=4219|s2cid=83943031 }}</ref>

The coelacanth was long considered a "[[living fossil]]" because scientists thought it was the sole remaining member of a [[taxon]] otherwise known only from fossils, with no close relatives alive,<ref name="ref1">{{cite book |last1=Forey |first1=Peter L |title=History of the Coelacanth Fishes |publisher=Chapman & Hall |year=1998 |isbn=978-0-412-78480-4 |location=London|pages=1, 3, 6, 13-16, 19, 27, 32, 35-40}}</ref>{{rp|1}} and that it evolved into roughly its current form approximately 400{{nbsp}}million years ago.<ref name="ref4">{{cite journal |doi=10.1098/rsbl.2006.0470 |title=Oldest coelacanth, from the Early Devonian of Australia |year=2006 |last1=Johanson |first1=Z. |last2=Long |first2=J. A |last3=Talent |first3=J. A |last4=Janvier |first4=P. |last5=Warren |first5=J. W |journal=Biology Letters |volume=2 |issue=3 |pages=443–6 |pmid=17148426 |pmc=1686207}}</ref> However, several more recent studies have shown that coelacanth body shapes are much more diverse than previously thought.<ref name="Friedman2007">{{cite journal |doi=10.1111/j.1525-142X.2007.00169.x |title=First discovery of a primitive coelacanth fin fills a major gap in the evolution of lobed fins and limbs |year=2007 |last1=Friedman |first1=Matt |last2=Coates |first2=Michael I. |last3=Anderson |first3=Philip |journal=Evolution & Development |volume=9 |issue=4 |pages=329–37 |pmid=17651357|s2cid=23069133 }}</ref><ref name="Friedman2006">{{cite journal |doi=10.1098/rspb.2005.3316 |title=A newly recognized fossil coelacanth highlights the early morphological diversification of the clade |year=2006 |last1=Friedman |first1=Matt |last2=Coates |first2=Michael I. |journal=Proceedings of the Royal Society B: Biological Sciences |volume=273 |issue=1583 |pages=245–50 |jstor=25223279 |pmid=16555794 |pmc=1560029}}</ref><ref name=Rebellatrix>{{cite journal |doi=10.1080/02724634.2012.657317 |title=A fork-tailed coelacanth, Rebellatrix divaricerca, gen. Et sp. Nov. (Actinistia, Rebellatricidae, fam. Nov.), from the Lower Triassic of Western Canada |year=2012 |last1=Wendruff |first1=Andrew J. |last2=Wilson |first2=Mark V. H. |journal=Journal of Vertebrate Paleontology |volume=32 |issue=3 |pages=499–511|bibcode=2012JVPal..32..499W |s2cid=85826893 }}</ref>

== Etymology ==
The word ''Coelacanth'' is an adaptation of the Modern Latin {{Lang|la|Cœlacanthus}} ('hollow spine'), from the [[Ancient Greek]] {{lang|grc|κοῖλ-ος}} ({{transliteration|grc|koilos}}, 'hollow') and {{lang|grc|ἄκανθ-α}} ({{transliteration|grc|akantha}}, 'spine'),<ref>{{cite web|title = The Coelancanth|url = http://www.actforlibraries.org/the-coelancanth/|website = actforlibraries.org|access-date = 2015-10-30}}</ref> referring to the hollow [[caudal fin]] rays of the first fossil specimen described and named by [[Louis Agassiz]] in 1839, belonging to the genus ''[[Coelacanthus]]''.<ref name=ref1 />{{rp|1}} The genus name ''Latimeria'' commemorates [[Marjorie Courtenay-Latimer]], who discovered the first specimen.<ref>{{cite web|title = Smithsonian Institution – The Coelacanth: More Living than Fossil|url = http://vertebrates.si.edu/fishes/coelacanth/coelacanth_wider.html|website = vertebrates.si.edu|access-date = 2015-10-30}}</ref>

== Discovery ==
[[File:Coelacanthus granulatus.JPG|left|thumb|Fossil of ''[[Coelacanthus|Coelacanthus granulatus]],'' the first described coelacanth, named by [[Louis Agassiz]] in 1839]]
The earliest fossils of coelacanths were discovered in the 19th century. Coelacanths, which are related to [[lungfish]]es and [[tetrapod]]s, were believed to have become [[extinction|extinct]] at the end of the [[Cretaceous]] period.<ref>{{cite web|title = Coelacanth – Deep Sea Creatures on Sea and Sky|url = http://www.seasky.org/deep-sea/coelacanth.html|website = seasky.org|access-date = 2015-10-27}}</ref> More closely related to tetrapods than to the [[ray-finned fish]], coelacanths were considered transitional species between fish and tetrapods.<ref>{{Cite journal |last=Meyer |first=Axel |title=Molecular evidence on the origin of tetrapods and the relationships of the coelacanth |journal=Trends in Ecology & Evolution |volume=10 |issue=3 |pages=111–116 |doi=10.1016/s0169-5347(00)89004-7 |pmid=21236972 |year=1995 |bibcode=1995TEcoE..10..111M |url=http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-36291 |type=Submitted manuscript}}</ref> On 22 December 1938, the first ''[[Latimeria]]'' specimen was found off the east coast of South Africa, off the [[Chalumna River]] (now Tyolomnqa).<ref name=Smith /><ref>{{Cite web |title=Marjorie Courtenay-Latimer |url=https://www.lindahall.org/about/news/scientist-of-the-day/marjorie-courtenay-latimer/ |date=24 February 2020|access-date=2024-12-20 |website=The Linda Hall Library |language=en-US}}</ref><ref>{{Cite journal |last=Smith |first=J. L. B. |date=March 1939 |title=A Living Fish of Mesozoic Type |url=https://www.nature.com/articles/143455a0 |journal=Nature |language=en |volume=143 |issue=3620 |pages=455–456 |doi=10.1038/143455a0 |bibcode=1939Natur.143..455S |issn=0028-0836}}</ref> Museum curator [[Marjorie Courtenay-Latimer]] discovered the fish among the catch of a local fisherman.<ref name=Smith /> Courtenay-Latimer contacted a Rhodes University ichthyologist, [[J. L. B. Smith]], sending him drawings of the fish, and he confirmed the fish's importance with a famous cable: "Most Important Preserve Skeleton and Gills = Fish Described."<ref name=Smith />

Its discovery 66 million years after its supposed extinction makes the coelacanth the best-known example of a [[Lazarus taxon]], an evolutionary line that seems to have disappeared from the fossil record only to reappear much later. Since 1938, [[West Indian Ocean coelacanth]] have been found in the [[Comoros]], [[Kenya]], [[Tanzania]], [[Mozambique]], [[Madagascar]], in [[iSimangaliso Wetland Park]], and off the South Coast of [[Kwazulu-Natal]] in South Africa.<ref name=venter>{{cite journal|last1=Venter|first1=P.|last2=Timm|first2=P.|last3=Gunn|first3=G.|last4=le Roux|first4=E.|last5=Serfontein|first5=C.|year=2000|title=Discovery of a viable population of coelacanths (''Latimeria chalumnae'' Smith, 1939) at Sodwana Bay, South Africa|journal=South African Journal of Science|volume=96|issue=11/12|pages=567–568}}</ref><ref name="Fraser et al 2020" >{{cite journal|url=https://www.sajs.co.za/article/view/7806/9870 |title=Live coelacanth discovered off the KwaZulu-Natal South Coast, South Africa  |journal=South African Journal of Science |volume=116 |issue=3/4 March/April 2020 |first1=Michael D. |last1=Fraser |first2=Bruce A.S. |last2=Henderson |first3=Pieter B. |last3=Carstens |first4=Alan D. |last4=Fraser |first5=Benjamin S. |last5=Henderson |first6=Marc D. |last6=Dukes |first7=Michael N. |last7=Bruton |doi=10.17159/sajs.2020/7806 |date=26 March 2020 |doi-access=free }}</ref>

The [[Comoro Islands]] specimen was discovered in December 1952.<ref>{{Cite news|url=https://www.newspapers.com/clip/11755015/prehistoric_fish_offers_rare_glimpse_of/|title=Prehistoric fish offers rare glimpse of hidden sea life – Coelacanth (1953)|date=1953-02-23|work=Abilene Reporter-News|access-date=2017-06-18|page=25}}</ref> Between 1938 and 1975, 84 specimens were caught and recorded.<ref>{{Cite news|url=https://www.newspapers.com/clip/11755368/70millionyearold_fish_dissected/|title=70-million-year-old fish dissected – Coaelacanth (1975)|date=1975-05-28|work=Redlands Daily Facts|access-date=2017-06-18|page=6}}</ref>

The second [[Extant taxon|extant]] species, the [[Indonesian coelacanth]], was described from [[Manado]], North Sulawesi, Indonesia, in 1999 by Pouyaud et al.<ref name=Pouyaud>{{cite journal |doi=10.1016/S0764-4469(99)80061-4 |title=Une nouvelle espèce de cœlacanthe. Preuves génétiques et morphologiques |trans-title=A new species of coelacanth. Genetic and morphologic proof |language=fr |year=1999 |last1=Pouyaud |first1=Laurent |last2=Wirjoatmodjo |first2=Soetikno |last3=Rachmatika |first3=Ike |last4=Tjakrawidjaja |first4=Agus |last5=Hadiaty |first5=Renny |last6=Hadie |first6=Wartono |journal=Comptes Rendus de l'Académie des Sciences |volume=322 |issue=4 |pages=261–7 |bibcode=1999CRASG.322..261P |pmid=10216801}}</ref> based on a specimen discovered by [[Mark V. Erdmann]] in 1998<ref name=Erdmann>{{cite journal |doi=10.1038/26376 |year=1998 |last1=Erdmann |first1=Mark V. |last2=Caldwell |first2=Roy L. |last3=Moosa |first3=M. Kasim |journal=Nature |volume=395 |issue=6700 |page=335 |bibcode=1998Natur.395..335E |title=Indonesian 'king of the sea' discovered|s2cid=204997216 |doi-access=free }}</ref> and deposited at the [[Indonesian Institute of Sciences]] (LIPI).<ref>{{cite journal |url=https://www.science.org/content/article/dispute-over-legendary-fish |title= Dispute Over a Legendary Fish|first= Constance |last=Holden|date=30 March 1999 |journal=Science |volume= 284|issue= 5411|pages= 22–3|doi= 10.1126/science.284.5411.22b|pmid= 10215525|s2cid= 5441807|url-access= subscription}}</ref> Erdmann and his wife Arnaz Mehta first encountered a specimen at a local market in September 1997, but took only a few photographs of the first specimen of this species before it was sold. After confirming that it was a unique discovery, Erdmann returned to Sulawesi in November 1997 to interview fishermen and look for further examples. A second specimen was caught by a fisherman in July 1998 and was then handed to Erdmann.<ref>{{cite journal |title=Coelacanth discovery in Indonesia |first=Henry |last=Gee |date= 1 October 1998 | journal=Nature | doi=10.1038/news981001-1 }}</ref><ref>{{cite web |url=http://www.ucmp.berkeley.edu/vertebrates/coelacanth/coelacanth1.html |title=The Discovery |publisher=University of California Museum of Paleontology }}</ref>

== Description ==
[[File:Latimeria chalumnae replica.jpg|thumbnail|Reconstruction of [[West Indian Ocean coelacanth]]]]
[[File:Latimeria menadoensis.jpg|thumb|upright|Preserved ''Latimeria menadoensis'', [[Tokyo Sea Life Park]], Japan]]
''[[Latimeria chalumnae]]'' and ''[[Latimeria menadoensis|L. menadoensis]]'' are the only two known living coelacanth species.<ref name="ref1" />{{rp|1,6}}<ref name="ref6">{{cite book |last1=Nelson |first1=Joseph S. |title=Fishes of the World |location=Hoboken, New Jersey |publisher=John Wiley |year=2006 |isbn=978-0-471-75644-6 |page=461}}</ref> Coelacanths are large, plump, lobe-finned fish that can grow to more than {{Convert|2|m|ft|abbr=on}} and weigh around {{Convert|90|kg|lb|abbr=on}}.<ref>{{cite web|title = Coelacanths, Coelacanth Pictures, Coelacanth Facts – National Geographic|url = http://animals.nationalgeographic.com/animals/fish/coelacanth/|archive-url = https://web.archive.org/web/20100114080556/http://animals.nationalgeographic.com/animals/fish/coelacanth|url-status = dead|archive-date = 14 January 2010|website = National Geographic|access-date = 2015-10-28|date = 2011-05-10}}</ref> They are estimated to live up to 100 years, based on analysis of annual growth marks on scales, and reach maturity around the age of 55;<ref>{{cite web |url=https://www.eurekalert.org/pub_releases/2021-06/cp-cml061021.php |title=Coelacanths may live nearly a century, five times longer than researchers expected |work=[[Eurekalert]] |date=17 June 2021 |access-date=17 June 2021}}</ref> the oldest known specimen was 84 years old at the time of its capture in 1960.<ref>{{cite journal |last1=Mahé |first1=Kélig |last2=Ernande |first2=Bruno |last3=Herbin |first3=Marc |title=New scale analyses reveal centenarian African coelacanths |journal=[[Current Biology]] |publisher=[[Cell Press]] |date=17 June 2021 |volume=31 |issue=16 |pages=3621–3628.e4 |doi=10.1016/j.cub.2021.05.054 |pmid=34143958 |issn=0960-9822|doi-access=free |bibcode=2021CBio...31E3621M }}</ref> 
Even though their estimated lifetime is similar to humans, gestation can last 5 years, which is 1.5 years more than the deep-sea [[frilled shark]], the previous record holder.<ref>{{cite magazine |url=https://www.economist.com/science-and-technology/2021/06/19/coelacanths-live-for-as-long-as-people |title=Coelacanths live for as long as people |magazine=[[The Economist]] |date=19 June 2021 |access-date=19 August 2021}}</ref>

They are nocturnal [[piscivorous]] drift-hunters.<ref name="ref7">{{cite journal |bibcode=1987Natur.329..331F |title=Locomotion of the coelacanth Latimeria chalumnae in its natural environment |last1=Fricke |first1=Hans |last2=Reinicke |first2=Olaf |last3=Hofer |first3=Heribert |last4=Nachtigall |first4=Werner |volume=329 |year=1987 |pages=331–3 |journal=Nature |doi=10.1038/329331a0 |issue=6137|s2cid=4353395 }}</ref>

The body is covered in [[Fish scale#Leptoid scales|ctenoid]] [[Fish scale#Elasmoid scales|elasmoid]] scales that act as armor.<ref name="Sherman 2016">{{Cite journal |last=Sherman |first=Vincent R. |title=A comparative study of piscine defense: The scales of ''Arapaima gigas'', ''Latimeria chalumnae'' and ''Atractosteus spatula'' |journal=Journal of the Mechanical Behavior of Biomedical Materials |volume=73 |pages=1–16 |year=2016 |doi=10.1016/j.jmbbm.2016.10.001 |pmid=27816416 }}</ref> Coelacanths have eight fins – two dorsal fins, two pectoral fins, two pelvic fins, one anal fin and one caudal fin. The tail is very nearly equally proportioned and is split by a terminal tuft of fin rays that make up its caudal lobe. The eyes of the coelacanth are very large, while the mouth is very small.{{citation needed|date=December 2021|reason=Contradicted by most every picture here, esp. the one adjacent to this text, dropped here 10 years ago (Jhende34) then editor disappeared, can't find any support for this statement "very small"}} The eye is acclimatized to seeing in poor light by rods that absorb mostly short wavelengths. Coelacanth vision has evolved to a mainly blue-shifted color capacity.<ref name="ref8">{{cite journal |bibcode=1999PNAS...96.6279Y |title=Adaptive Evolution of Color Vision of the Comoran Coelacanth (''Latimeria chalumnae'') |last1=Yokoyama |first1=Shozo |last2=Zhang |first2=Huan |last3=Radlwimmer |first3=F. Bernhard |last4=Blow |first4=Nathan S. |volume=96 |year=1999 |pages=6279–84 |journal=Proceedings of the National Academy of Sciences of the United States of America |doi=10.1073/pnas.96.11.6279 |pmid=10339578 |issue=11 |pmc=26872 |jstor=47861|doi-access=free }}</ref> [[maxilla|Pseudomaxillary]] folds surround the mouth and replace the maxilla, a structure absent in coelacanths. Two nostrils, along with four other external openings, appear between the premaxilla and lateral [[Anatomical terms of location#Other directional terms|rostral]] bones. The nasal sacs resemble those of many other fish and do not contain an internal nostril. The coelacanth's rostral organ, contained within the [[ethmoid]] region of the braincase, has three unguarded openings into the environment and is used as a part of the coelacanth's laterosensory system.<ref name="ref1" />{{rp|14-16, 19}} The coelacanth's auditory reception is mediated by its inner ear, which is very similar to that of tetrapods and is classified as being a [[basilar papilla]].<ref name="ref9">{{cite journal |bibcode=1987Natur.327..153F |title=Inner ear of the coelacanth fish ''Latimeria'' has tetrapod affinities |last1=Fritzsch |first1=B. |volume=327 |year=1987 |pages=153–4 |journal=Nature |doi=10.1038/327153a0 |pmid=22567677 |issue=6118|s2cid=4307982 }}</ref>

Coelacanths are a part of the [[clade]] [[Sarcopterygii]], or the lobe-finned fishes. They share membership in this clade with lungfish and tetrapods. Externally, several characteristics distinguish coelacanths from other lobe-finned fish. They possess a three-lobed [[caudal fin]], also called a trilobate fin or a diphycercal tail. A secondary tail extending past the primary tail separates the upper and lower halves of the coelacanth. Ctenoid elasmoid scales act as thick armor to protect the coelacanth's exterior. Several internal traits also aid in differentiating coelacanths from other lobe-finned fish. At the back of the skull, the coelacanth possesses a hinge, the [[intracranial]] joint, which allows it to open its mouth extremely wide. Coelacanths also retain an oil-filled [[notochord]], a hollow, pressurized tube which is replaced by a [[vertebral column]] early in embryonic development in most other vertebrates.<ref>{{Cite web|url=http://www.scienceinafrica.co.za/2002/february/coela.htm|archive-url=https://web.archive.org/web/20130921055458/http://www.scienceinafrica.co.za/2002/february/coela.htm|url-status=dead|title=What do we know about the coelacanths – Science in Africa|archive-date=21 September 2013}}</ref> The coelacanth's heart is shaped differently from that of most modern fish, with its chambers arranged in a straight tube. The coelacanth's [[braincase]] is 98.5% filled with fat; only 1.5% of the braincase contains brain tissue. The cheeks of the coelacanth are unique because the [[Operculum (fish)|opercular]] bone is very small and holds a large soft-tissue opercular flap. A spiracular chamber is present, but the [[Spiracle (vertebrates)|spiracle]] is closed and never opens during development.<ref>{{Cite book|url=https://books.google.com/books?id=4j9AKGsQ1msC&q=%22spiracular+chamber+is+closed+in+coelacanths%22&pg=PA391|title=Gaining Ground, Second Edition: The Origin and Evolution of Tetrapods|first=Jennifer A.|last=Clack|date=27 June 2012|page=391|publisher=Indiana University Press|isbn=978-0-253-00537-3}}</ref><ref name="ref1" />{{rp|15}}<ref name="ref5">{{cite web |title=The Coelacanth – a Morphological Mixed Bag |publisher=ReefQuest Centre for Shark Research |url=http://www.elasmo-research.org/education/classification/coelacanth.htm}}</ref> Also unique to extant coelacanths is the presence of a "fatty lung" or a fat-filled single-lobed [[vestigial]] [[lung]], homologous to other fishes' [[swim bladder]]s. The parallel development of a fatty organ for buoyancy control suggests a unique specialization for deep-water habitats. There are small and hard but flexible plates around the vestigial lung in adult specimens, though not around the fatty organ. The plates most likely had a regulation function for the volume of the lung.<ref name="Brito">{{cite journal |doi=10.1111/j.1475-4983.2010.01015.x |title=The histological structure of the calcified lung of the fossil coelacanth ''Axelrodichthys araripensis'' (Actinistia: Mawsoniidae) |year=2010 |last1=Brito |first1=Paulo M. |last2=Meunier |first2=François J. |last3=Clément |first3=Gael |last4=Geffard-Kuriyama links|first4=Didier |journal=Palaeontology |volume=53 |issue=6 |pages=1281–90|bibcode=2010Palgy..53.1281B |doi-access=free }}</ref> Due to the size of the fatty organ, researchers assume that it is responsible for the kidney's unusual relocation. The two kidneys, which are fused into one,<ref>{{Cite book|url=https://books.google.com/books?id=hPEJAwAAQBAJ&q=%22amounts.+The+paired+kidneys+are+fused%2C+%22&pg=PA92|title=From fish to philosopher|first=H. W.|last=Smith|date=24 October 2018|publisher=Рипол Классик|isbn=9785873926930|page=92}}</ref> are located ventrally within the abdominal cavity, posterior to the cloaca.<ref>{{Cite book|url=https://books.google.com/books?id=wHZ6WwqbrmkC&q=%22amongst+vertebrates+in+being+located+ventrally%22&pg=PA26|title=History of the Coelacanth Fishes|first=Peter|last=Forey|date=30 November 1997|publisher=Springer Science & Business Media|isbn=978-0-412-78480-4|page=26}}</ref>

[[File:Latimeria chalumnae.jpg|thumbnail|West Indian Ocean coelacanth caught on 21 January 1965, near [[Mutsamudu]] (Anjouan, Comoro Islands)]]
[[File:Pectoral fin Latimeria chalumnae.jpg|thumb|[[Pectoral fin]] of a West Indian Ocean coelacanth]]

=== Genetics ===
In 2013, a research group published the [[genome sequence]] of the coelacanth in the scientific journal ''[[Nature (journal)|Nature]]''.<ref name="genome">{{cite journal | title = The African coelacanth genome provides insights into tetrapod evolution | journal = Nature | date = 18 April 2013 | doi = 10.1038/nature12027 | last1 = Amemiya | first1 = Chris T. | last2 = Alföldi | first2 = Jessica | last3 = Lee | first3 = Alison P. | last4 = Fan | first4 = Shaohua | last5 = Philippe | first5 = Hervé | last6 = MacCallum | first6 = Iain | last7 = Braasch | first7 = Ingo | last8 = Manousaki | first8 = Tereza | last9 = Schneider | first9 = Igor | volume = 496 | issue = 7445 | pages = 311–6 | pmid = 23598338 | pmc = 3633110|bibcode = 2013Natur.496..311A | display-authors = 9 | last10 = Rohner | first10 = Nicolas | last11 = Organ | first11 = Chris | last12 = Chalopin | first12 = Domitille | last13 = Smith | first13 = Jeramiah J. | last14 = Robinson | first14 = Mark | last15 = Dorrington | first15 = Rosemary A. | last16 = Gerdol | first16 = Marco | last17 = Aken | first17 = Bronwen | last18 = Biscotti | first18 = Maria Assunta | last19 = Barucca | first19 = Marco | last20 = Baurain | first20 = Denis | last21 = Berlin | first21 = Aaron M. | last22 = Blatch | first22 = Gregory L. | last23 = Buonocore | first23 = Francesco | last24 = Burmester | first24 = Thorsten | last25 = Campbell | first25 = Michael S. | last26 = Canapa | first26 = Adriana | last27 = Cannon | first27 = John P. | last28 = Christoffels | first28 = Alan | last29 = De Moro | first29 = Gianluca | last30 = Edkins | first30 = Adrienne L. }}</ref>

Due to their lobed fins and other features, it was once hypothesized that the coelacanth might be the youngest diverging non-[[tetrapod]] [[Sarcopterygii|sarcopterygian]].<ref name=ref9 /><ref>{{cite journal |doi=10.1002/jmor.1051900418|title=Lungfish neural characters and their bearing on sarcopterygian phylogeny|journal=Journal of Morphology|volume=190|pages=277–297|year=1986|last1=Northcutt|first1=R. Glenn|hdl=2027.42/50281|s2cid=35473487|url=https://deepblue.lib.umich.edu/bitstream/2027.42/50281/1/1051900418_ftp.pdf|hdl-access=free}}</ref> But after sequencing the full genome of the coelacanth, it was discovered that the lungfish instead is more closely related to tetrapods. Coelacanths and [[rhipidistia]]ns (the [[concestor]] of lungfish and tetrapods) had already diverged from each other before the lungfish made the transition to land.<ref name="smithsonianmag.com">{{cite web|url=http://www.smithsonianmag.com/science-nature/dna-sequencing-reveals-that-coelacanths-werent-the-missing-link-between-sea-and-land-25025860/?no-ist|title=DNA Sequencing Reveals that Coelacanths Weren't the Missing Link Between Sea and Land|first=Joseph|last=Stromberg|publisher=Smithsonian Magazine}}</ref>

Another important discovery made from the genome sequencing is that the coelacanths are still evolving today. While phenotypic similarity between extant and extinct coelacanths suggests there is limited [[evolutionary pressure]] on these organisms to undergo morphological divergence, they are undergoing measurable genetic divergence. Despite prior studies showing that protein coding regions are undergoing evolution at a substitution rate much lower than other sarcopterygians (consistent with phenotypic stasis observed between extant and fossil members of the taxa), the non-coding regions subject to higher transposable element activity show marked divergence even between the two extant coelacanth species.<ref name="genome" /> This has been facilitated in part by a coelacanth-specific endogenous retrovirus of the Epsilon retrovirus family.<ref>{{Cite journal|doi=10.1371/journal.pone.0114382|doi-access=free|title=Interspecies Insertion Polymorphism Analysis Reveals Recent Activity of Transposable Elements in Extant Coelacanths|year=2014|last1=Naville|first1=Magali|last2=Chalopin|first2=Domitille|last3=Volff|first3=Jean-Nicolas|journal=PLOS ONE|volume=9|issue=12|pages=e114382|pmid=25470617|pmc=4255032|bibcode=2014PLoSO...9k4382N}}</ref>[[File:Fishapods.svg|thumb|upright=1.4|In the [[Devonian|Late Devonian]] [[vertebrate]] speciation, descendants of [[Pelagic zone|pelagic]] [[Sarcopterygii|lobe-finned fish]]—like ''[[Eusthenopteron]]''—exhibited a sequence of adaptations: ''[[Panderichthys]]'', suited to muddy shallows; ''[[Tiktaalik]]'' with limb-like fins that could take it up onto land; and [[Tetrapod|Early tetrapods]] in weed-filled swamps, such as ''[[Acanthostega]]'' which had feet with eight digits and ''[[Ichthyostega]]'' with limbs. Descendants also included pelagic lobe-finned fish such as the coelacanth species.]]

== Evolution and taxonomy ==
[[File:Libys sp.jpg|thumb|Specimen of ''[[Libys]]'' (Latimeriidae) from the Upper Jurassic of Germany]]
[[File:Mawsonia scaling.png|thumb|320x320px|Estimated size of the largest known individual of the Jurassic-Cretaceous freshwater coelacanth ''[[Mawsonia (fish)|Mawsonia]]'' compared to a human]]
[[File:Allenypterus montanus (Restoration).jpg|thumb|Life restoration of the basal coelacanth ''[[Allenypterus]]'' from the Carboniferous of North America]]
Coelacanths are members of the class Actinistia, with many researchers considering the term "coelacanth" to cover all members of Actinistia.<ref name=":0">{{Cite journal |last1=Toriño |first1=Pablo |last2=Soto |first2=Matías |last3=Perea |first3=Daniel |date=2021-02-25 |title=A comprehensive phylogenetic analysis of coelacanth fishes (Sarcopterygii, Actinistia) with comments on the composition of the Mawsoniidae and Latimeriidae: evaluating old and new methodological challenges and constraints |url=https://www.researchgate.net/publication/349631865 |journal=Historical Biology |volume=33 |issue=12 |pages=3423–3443 |bibcode=2021HBio...33.3423T |doi=10.1080/08912963.2020.1867982 |issn=0891-2963 |s2cid=233942585}}</ref><ref name=":1" /> The order Coelacanthiformes has been used for a subgroup of actinistians, containing the modern coelacanths.<ref>{{Cite journal |last=Arratia |first=Gloria |last2=Schultze |first2=Hans-Peter |date=2015-09-03 |title=A new fossil actinistian from the Early Jurassic of Chile and its bearing on the phylogeny of Actinistia |url=http://www.tandfonline.com/doi/full/10.1080/02724634.2015.983524 |journal=Journal of Vertebrate Paleontology |language=en |volume=35 |issue=5 |pages=e983524 |doi=10.1080/02724634.2015.983524 |issn=0272-4634|url-access=subscription }}</ref> According to the fossil record, the divergence of coelacanths, [[lungfish]], and [[tetrapods]] is thought to have occurred during the [[Silurian]].<ref>{{Cite journal|last1=Lu|first1=Jing|last2=Giles|first2=Sam|last3=Friedman|first3=Matt|last4=Zhu|first4=Min|date=2017-12-05|title=A new stem sarcopterygian illuminates patterns of character evolution in early bony fishes|journal=Nature Communications|language=en|volume=8|issue=1|pages=1932|doi=10.1038/s41467-017-01801-z|pmid=29203766|issn=2041-1723|pmc=5715141|bibcode=2017NatCo...8.1932L}}</ref> Over 100 fossil species of coelacanth have been described.<ref name=":0" /> The oldest identified coelacanth fossils are around 420–410 million years old, dating to the [[Pragian]] stage of the early [[Devonian]]. These include ''[[Eoactinistia]]'' from Australia, known only from a fragmentary jaw, as well as ''[[Euporosteus|Euporosteus yunnanensis]]'' from China, known from a partial skull that indicates it to be the earliest anatomically modern coelacanth.<ref name="ref4" /><ref name=":1">{{Cite journal |last=Zhu |first=Min |last2=Yu |first2=Xiaobo |last3=Lu |first3=Jing |last4=Qiao |first4=Tuo |last5=Zhao |first5=Wenjin |last6=Jia |first6=Liantao |date=2012-04-10 |title=Earliest known coelacanth skull extends the range of anatomically modern coelacanths to the Early Devonian |url=https://www.nature.com/articles/ncomms1764 |journal=Nature Communications |language=en |volume=3 |issue=1 |pages=772 |doi=10.1038/ncomms1764 |issn=2041-1723}}</ref> Some authors have also suggested that the slightly older [[Onychodontiformes|onychodont]] ''[[Styloichthys]]'' may also be an early coelacanth.<ref>{{cite journal|last=Friedman|first=Matt|date=10 August 2007|title=Styloichthys as the oldest coelacanth: implications for early osteichthyan interrelationships |url=https://www.tandfonline.com/doi/abs/10.1017/S1477201907002052 |journal=Journal of Systematic Palaeontology|volume=5|issue=3|pages=289–343|doi=10.1017/S1477201907002052|bibcode=2007JSPal...5..289F |s2cid=83712134|access-date=2007-12-28|url-access=subscription}}</ref> 

Coelacanths were never a diverse group in comparison to other groups of fish, and reached a peak diversity during the [[Early Triassic]] (252–247 million years ago),<ref name="Cavin&al.2020" /> coinciding with a burst of diversification between the Late Permian and Middle Triassic.<ref name=":0" /> Most [[Mesozoic]] coelacanths belong to the suborder Latimerioidei, which contains two major subdivisions, the marine [[Latimeriidae]], which contains modern coelacanths, as well as the extinct [[Mawsoniidae]], which were native to [[Brackish water|brackish]], freshwater as well as marine environments.<ref>{{Cite journal|last1=Cavin|first1=Lionel|last2=Cupello|first2=Camila|last3=Yabumoto|first3=Yoshitaka|last4=Léo|first4=Fragoso|last5=Deersi|first5=Uthumporn|last6=Brito|first6=Paul M.|date=2019|title=Phylogeny and evolutionary history of mawsoniid coelacanths|url=http://www.kmnh.jp/wp-content/uploads/2019/05/A17-3-Cavin.pdf|journal=Bulletin of the Kitakyushu Museum of Natural History and Human History, Series A|volume=17|pages=3–13}}</ref>

Paleozoic coelacanths are generally small (~{{Cvt|30–40|cm|disp=or}} in length), while Mesozoic forms were larger.<ref name=":0" /> Several specimens belonging to the Jurassic and Cretaceous mawsoniid coelacanth genera ''[[Trachymetopon]]'' and ''[[Mawsonia (fish)|Mawsonia]]'' likely reached or exceeded {{Convert|5|m|ft|abbr=off}} in length, making them amongst the largest known fishes of the Mesozoic, and amongst the largest bony fishes of all time.<ref>{{Cite journal|last1=Cavin|first1=Lionel|last2=Piuz|first2=André|last3=Ferrante|first3=Christophe|last4=Guinot|first4=Guillaume|date=2021-06-03|title=Giant Mesozoic coelacanths (Osteichthyes, Actinistia) reveal high body size disparity decoupled from taxic diversity|journal=Scientific Reports|language=en|volume=11|issue=1|pages=11812|doi=10.1038/s41598-021-90962-5|pmid=34083600|issn=2045-2322|pmc=8175595|bibcode=2021NatSR..1111812C}}</ref>

The most recent fossil latimeriid is ''[[Megalocoelacanthus|Megalocoelacanthus dobiei]]'', whose disarticulated remains are found in late [[Santonian]] to middle [[Campanian]], and possibly earliest [[Maastrichtian]]-aged marine strata of the Eastern and Central United States,<ref name="Schwimmer&al.1994">{{cite journal|last1=Schwimmer|first1=D.R.|author2=Stewart, J.D.|author3=Williams, G.D.|title=Giant fossil coelacanths of the Late Cretaceous in the eastern United States|journal=Geology|date=1994|volume=2|issue=6|pages=503–506|doi=10.1130/0091-7613(1994)022<0503:GFCOTL>2.3.CO;2|bibcode=1994Geo....22..503S}}</ref><ref name="gottfried">{{cite journal|author1=Gottfried, Michael D. |author2=Rogers, Raymond R. |author3=Rogers, K. Curry   |title=First record of Late Cretaceous coelacanths from Madagascar|url=https://www.researchgate.net/publication/265667981|journal= Recent Advances in the Origin and Early Radiation of Vertebrates |year=2004|pages= 687–691}}</ref><ref name="Dutel&al.2012">{{cite journal|last1=Dutel|first1=H.|author2=Maisey, J.P.|author3=Schwimmer, D.R.|author4=Janvier, P.|author5=Herbin, M.|author6=Clément, G.|title= The Giant Cretaceous Coelacanth (Actinistia, Sarcopterygii) Megalocoelacanthus dobiei Schwimmer, Stewart & Williams, 1994, and Its Bearing on Latimerioidei Interrelationships|journal=PLOS ONE|year=2012|volume= 7|issue= 11|pages= e49911|doi=10.1371/journal.pone.0049911|pmid= 23209614|pmc= 3507921|bibcode=2012PLoSO...749911D|doi-access=free}}</ref> the most recent mawsoniids are ''[[Axelrodichthys|Axelrodichthys megadromos]]'' from early Campanian to early Maastrichtian freshwater continental deposits of France,<ref name="Cavin&al.2005">{{cite journal|last1=Cavin|first1=L.|author2=Forey, P.L.|author3=Tong, H.|author4=Buffetaut, E.|title=Latest European coelacanth shows Gondwanan affinities|journal=Biology Letters|date=2005|volume=1|issue=2|pages=176–177|doi=10.1098/rsbl.2004.0287|pmid=17148159|pmc=1626220}}</ref><ref name="Cavin&al.2016">{{cite journal|last1=Cavin|first1=L.|author2=Valentin, X.|author3=Garcia, G.|title=A new mawsoniid coelacanth (Actinistia) from the Upper Cretaceous of Southern France|journal=Cretaceous Research|date=2016|volume=62|pages=65–73|doi=10.1016/j.cretres.2016.02.002|bibcode=2016CrRes..62...65C }}</ref><ref name="Cavin&al.2020">{{cite journal|last1=Cavin|first1=L.|author2=Buffetaut, E.|author3=Dutour, Y.|author4=Garcia, G.|author5=Le Loeuff, J.|author6=Méchin, A.|author7=Méchin, P.|author8=Tong, H.|author9=Tortosa, T.|author10=Turini, E.|author11=Valentin, X.|title=The last known freshwater coelacanths: New Late Cretaceous mawsoniids remains (Osteichthyes: Actinistia) from Southern France|journal=PLOS ONE|date=2020|volume=15|issue=6|pages=e0234183|doi=10.1371/journal.pone.0234183|pmc=7274394|pmid=32502171|bibcode=2020PLoSO..1534183C|doi-access=free}}</ref> as well as an indeterminate marine mawsoniid from Morocco, dating to the late Maastrichtian<ref name="Brito&al.2021">{{cite journal|last1=Brito|first1=P.M.|author2=Martill, D.M.|author3=Eaves, I.|author4=Smith, R.E.|author5=Cooper, S.L.A.|year=2021|title=A marine Late Cretaceous (Maastrichtian) coelacanth from North Africa|journal=Cretaceous Research|volume=122|page=104768|doi=10.1016/j.cretres.2021.104768|bibcode=2021CrRes.12204768B |s2cid=233551515|url=https://researchportal.port.ac.uk/portal/en/publications/a-marine-late-cretaceous-maastrichtian-coelacanth-from-north-africa(c8521ebb-5597-4a15-9320-961113ee06d9).html |url-access=subscription}}</ref> A small bone fragment from the [[Europe]]an [[Paleocene]] has been considered the only plausible post-Cretaceous record, but this identification is based on comparative bone histology methods of doubtful reliability.<ref name="Schwimmer&al.1994" /><ref>{{cite journal |last1=Ørvig |first1=Tor |title=A vertebrate bone from the Swedish Paleocene |journal=Geologiska Föreningen i Stockholm Förhandlingar |date=1 June 1986 |volume=108 |issue=2 |pages=139–141 |doi=10.1080/11035898609452636 |issn=0016-786X}}</ref>

Living coelacanths have been considered "living fossils" based on their supposedly conservative [[morphology (biology)|morphology]] relative to fossil species;<ref name="ref10">{{cite journal |last=Butler |first=Carolyn |title=Living Fossil Fish |journal=National Geographic |date=March 2011 |pages=86–93}}</ref><ref name="ref1" />{{rp|1}} however, recent studies have expressed the view that coelacanth morphologic conservatism is a belief not based on data.<ref name="Friedman2007" /><ref name="Friedman2006" /><ref name="Rebellatrix" /><ref name="Casane">{{cite journal |doi=10.1002/bies.201200145 |title=Why coelacanths are not 'living fossils' |year=2013 |last1=Casane |first1=Didier |last2=Laurenti |first2=Patrick |journal=BioEssays |volume=35 |issue=4 |pages=332–8 |pmid=23382020|s2cid=2751255 |doi-access=free }}</ref> Fossils suggest that coelacanths were most morphologically diverse during the Devonian and Carboniferous, while Mesozoic species are generally morphologically similar to each other.<ref name=":0" />

[[Cladogram]] showing the relationships of coelacanth genera after Torino, Soto and Perea, 2021.<ref name=":0" />

{{clade |style=font-size:90%; line-height:90%;
|1=''[[Mimipiscis]]'' ([[Actinopterygii]])
|2=''[[Porolepis]]'' ([[Porolepiformes]])
|label3='''Actinistia'''
|3={{clade
|1=''[[Miguashaia]]''
|2=''[[Styloichthys]]''
|3=''[[Gavinia]]''
|4={{clade
|1=''[[Diplocercides]]''
|2={{clade
|1=''[[Serenichthys]]''
|2={{clade
|1=''[[Holopterygius]]''
|2=''[[Allenypterus]]''}} 
|3={{clade
|1=''[[Lochmocercus]]''
|2={{clade
|1={{clade
|1=''[[Polyosteorhynchus]]''
|2={{clade 
|1=''[[Rebellatrix]]''
|2=''[[Hadronector]]''}} }}
|2={{clade
|1=''[[Rhabdoderma]]''
|2={{clade
|1=''[[Caridosuctor]]''
|2={{clade
|1={{clade
|1=''[[Sassenia]]''
|2=''[[Spermatodus]]''}}
|2={{clade
|1={{clade
|1=''[[Piveteauia]]''
|2={{clade
|1=''[[Coccoderma]]''
|2=''[[Laugia]]''}} }}
|2={{clade
|1=''[[Coelacanthus]]''
|2={{clade
|1=''[[Guizhoucoelacanthus]]''
|2={{clade
|1={{clade
|1=''[[Wimania]]''
|2=''[[Axelia]]''}} 
|2={{clade
|1=''[[Whiteia]]''
|2={{clade
|1=''[[Heptanema]]''
|2=''[[Dobrogeria]]''
|label3=[[Latimerioidei]]
|3={LATIMERIOIDEA}
}} }} }} }} }} }} }} }} }} }} }} }} }} }}
|targetA={LATIMERIOIDEA}
|subcladeA={{clade
   |label1=[[Mawsoniidae]]
   |1={{clade
      |1={{clade
         |1=''[[Atacamaia]]''
         |2=''[[Luopingcoelacanthus]]''
         }}
      |2={{clade
         |1=''[[Yunnancoelacanthus]]''
         |2={{clade
            |1=''[[Chinlea]]''
            |2={{clade
               |1=''[[Parnaibaia]]''
               |2={{clade
                  |1=''[[Trachymetopon]]''
                  |2=''[[Lualabaea]]''
                  |3={{clade
                     |1=''[[Axelrodichthys]]''
                     |2=''[[Mawsonia (fish)|Mawsonia]]''
                     }}
                  }} 
               }} 
            }} 
         }} 
      }}
   |label2=[[Latimeriidae]]
   |2={{clade
      |1=''[[Garnbergia]]''
      |2={{clade
         |1=''[[Diplurus]]''
         |2={{clade
            |1={{clade
               |1=''[[Megalocoelacanthus]]''
               |2=''[[Libys]]''
               }} 
            |2={{clade
               |1={{clade
                  |1=''[[Ticinepomis]]''
                  |2=''[[Foreyia]]''
                  }}
               |2={{clade
                  |1=''[[Holophagus]]''
                  |2={{clade
                     |1=''[[Undina (fish)|Undina]]''
                     |2={{clade
                        |1=''[[Macropoma]]''
                        |2={{clade
                           |1=''[[Swenzia]]''
                           |2=''[[Latimeria]]''
                           }} 
                        }} 
                     }} 
                  }} 
               }} 
            }} 
         }} 
      }} 
   }} 
}}

=== Timeline of genera ===
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 from: -488.3    till: -443.7    color:ordovician    text:[[Ordovician]]
 from: -443.7    till: -416    color:silurian    text:[[Silurian]]
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 from: -359.2    till: -299   color:carboniferous    text:[[Carboniferous]]
 from: -299    till: -251   color:permian    text:[[Permian]]
 from: -251    till: -199.6  color:triassic    text:[[Triassic]]
 from: -199.6    till: -145.5   color:jurassic    text:[[Jurassic]]
 from: -145.5   till: -66   color:cretaceous    text:[[Cretaceous]]
 from: -66    till: -23.03   color:paleogene    text:[[Paleogene]]
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 from:  -542   till:  -251    color:paleozoic    text:[[Paleozoic Era]]
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 color:devonian bar:NAM3 from:-412.8    till:-411.2 text:[[Powichthys]]
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 color:devonian bar:NAM13 from:-397.5    till:-359.2 text:[[Strunius]]
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 color:devonian bar:NAM20 from:-385.3    till:-381.7 text:[[Miguashaia]]
 color:devonian bar:NAM21 from:-385.3    till:-374.5 text:[[Nesides]]
 color:devonian bar:NAM22 from:-381.7    till:-328.3 text:[[Diplocercides]]
 color:devonian bar:NAM26 from:-364.3    till:-359.2 text:[[Chagrinia]]
 color:carboniferous bar:NAM29 from:-345.3    till:-299 text:[[Rhabdoderma]]
 color:carboniferous bar:NAM30 from:-333.97    till:-328.3 text:[[Coelacanthopsis]]
 color:carboniferous bar:NAM31 from:-328.3    till:-324.9 text:[[Allenypterus]]
 color:carboniferous bar:NAM32 from:-328.3    till:-324.9 text:[[Caridosuctor]]
 color:carboniferous bar:NAM33 from:-328.3    till:-324.9 text:[[Hadronector]]
 color:carboniferous bar:NAM34 from:-328.3    till:-324.9 text:[[Lochmocereus]]
 color:carboniferous bar:NAM35 from:-328.3    till:-324.9 text:[[Polyosteorhynchus]]
 color:carboniferous bar:NAM36 from:-306.5    till:-301.37 text:[[Synaptotylus]]
 color:permian bar:NAM37 from: -299    till:-294.6 text:[[Ectosteorhachis]]
 color:permian bar:NAM38 from:-260    till:-251 text:[[Changxingia]]
 color:permian bar:NAM39 from:-258.0    till:-252 text:[[Coelacanthus]]
 color:permian bar:NAM40 from:-255    till:-251 text:[[Yonngichthys]]
 color:triassic bar:NAM41 from:-251    till:-250.57 text:[[Laugia]]
 color:triassic bar:NAM42 from:-251    till:-248.13 text:[[Sassenia]]
 color:triassic bar:NAM43 from:-251    till:-245 text:[[Sinocoelacanthus]]
 color:triassic bar:NAM44 from:-250.13    till:-249.7 text:[[Piveteauia]]
 color:triassic bar:NAM45 from:-250.13    till:-249.7 text:[[Whiteia]]
 color:triassic bar:NAM46 from:-249.7    till:-248.13 text:[[Axelia]]
 color:triassic bar:NAM47 from:-249.7    till:-248.13 text:[[Mylacanthus]]
 color:triassic bar:NAM48 from:-249.7    till:-248.13 text:[[Scleracanthus]]
 color:triassic bar:NAM49 from:-249.7    till:-248.13 text:[[Wimania]]
 color:triassic bar:NAM50 from:-245    till:-237 text:[[Garnbergia]]
 color:triassic bar:NAM51 from:-242    till:-237 text:[[Heptanema]]
 color:triassic bar:NAM52 from:-237    till:-234 text:[[Alcoveria]]
 color:triassic bar:NAM53 from:-237    till:-234 text:[[Ticinepomis]]
 color:triassic bar:NAM54 from:-237    till:-228 text:[[Hainbergia]]
 color:triassic bar:NAM55 from:-220.3    till:-216.5 text:[[Graphiuricthys]]
 color:jurassic bar:NAM56 from:-199.6    till:-191 text:[[Holophagus]]
 color:jurassic bar:NAM57 from:-199    till:-163.5 text:[[Trachymetopon]]
 color:jurassic bar:NAM57.1 from:-163.5  till:-157.3 text:[[Swenzia]]
 color:jurassic bar:NAM58 from:-161.2    till:-145.5 text:[[Lualabaea]]
 color:jurassic bar:NAM59 from:-152    till:-145 text:[[Undina]]
 color:jurassic bar:NAM60 from:-150.8    till:-149.03 text:[[Coccoderma]]
 color:jurassic bar:NAM60.1 from:-150.8    till:-149.03 text:[[Libys]]
 color:cretaceous bar:NAM60.2 from:-150   till:-95 text:[[Mawsonia (fish)|Mawsonia]]
 color:cretaceous bar:NAM60.3 from:-112    till:-71.5 text:[[Axelrodichthys]]
 color:cretaceous bar:NAM60.6 from:-112    till:-79.2 text:[[Macropoma]]
 color:cretaceous bar:NAM61 from:-99.6    till:-93.5 text:[[Macropomoides]]
 color:cretaceous bar:NAM62 from:-86.3   till:-71.5 text:[[Megalocoelacanthus]]
 color:cretaceous bar:NAM62.1 from:-67   till:-65 text:[[Coelacanth|Mawsoniidae indeterminate]]
 color:cretaceous bar:NAM63 from:-65    till:-64 text: [[Post Cretaceous Coelacanth fossils|Coelacanthiformes indeterminate]]?
 color:quaternary bar:NAM64 from:-1    till:0 text:[[Latimeria]]

PlotData=
 align:center textcolor:black fontsize:M mark:(line,black) width:25

 bar:period
 from: -542    till:  -488.3   color:cambrian  text:[[Cambrian]]
 from: -488.3    till: -443.7    color:ordovician    text:[[Ordovician]]
 from: -443.7    till: -416    color:silurian    text:[[Silurian]]
 from: -416    till: -359.2   color:devonian    text:[[Devonian]]
 from: -359.2    till: -299   color:carboniferous    text:[[Carboniferous]]
 from: -299    till: -251   color:permian    text:[[Permian]]
 from: -251    till: -199.6  color:triassic    text:[[Triassic]]
 from: -199.6    till: -145.5   color:jurassic    text:[[Jurassic]]
 from: -145.5   till: -66   color:cretaceous    text:[[Cretaceous]]
 from: -66    till: -23.03   color:paleogene    text:[[Paleogene]]
 from: -23.03    till: -2.588   color:neogene    text:[[Neogene|Neog.]]
 from: -2.588    till: 0   color:quaternary    text:[[Quaternary|Q.]]

 bar:era
 from:  -542   till:  -251    color:paleozoic    text:[[Paleozoic Era]]
 from:  -251   till:  -66    color:mesozoic    text:[[Mesozoic Era]]
 from:  -66   till:  0   color:cenozoic    text:[[Cenozoic]]
</timeline>

== Distribution and habitat ==
[[File:Latimeria distribution RUS.png|thumb|upright=1.3|Geographical distribution of coelacanth]]
The current coelacanth range is primarily along the eastern African coast, although ''Latimeria menadoensis'' was discovered off Indonesia. Coelacanths have been found in the waters of Kenya, Tanzania, Mozambique, South Africa, Madagascar, Comoros and Indonesia.<ref name="ref10" /> Most ''Latimeria chalumnae'' specimens that have been caught have been captured around the islands of Grande Comore and Anjouan in the Comoros Archipelago (Indian Ocean). Though there are cases of ''L.&nbsp;chalumnae'' caught elsewhere, amino acid sequencing has shown no big difference between these exceptions and those found around Comore and Anjouan. Even though these few may be considered strays, there are several reports of coelacanths being caught off the coast of Madagascar. This leads scientists to believe that the endemic range of ''Latimeria chalumnae'' coelacanths stretches along the eastern coast of Africa from the Comoros Islands, past the western coast of Madagascar to the South African coastline.<ref name="ref1" />{{rp|13, 32, 35}} Mitochondrial DNA sequencing of coelacanths caught off the coast of southern Tanzania suggests a divergence of the two populations some 200,000 years ago. This could refute the theory that the Comoros population is the main population while others represent recent offshoots.<ref>{{Cite journal|title = Genetically distinct coelacanth population off the northern Tanzanian coast|journal = Proceedings of the National Academy of Sciences|date = 2011-11-01|pmc = 3207662|pmid = 22025696|pages = 18009–18013|volume = 108|issue = 44|doi = 10.1073/pnas.1115675108|first1 = Masato|last1 = Nikaido|first2 = Takeshi|last2 = Sasaki|first3 = J. J.|last3 = Emerson|first4 = Mitsuto|last4 = Aibara|first5 = Semvua I.|last5 = Mzighani|first6 = Yohana L.|last6 = Budeba|first7 = Benjamin P.|last7 = Ngatunga|first8 = Masamitsu|last8 = Iwata|first9 = Yoshitaka|last9 = Abe|bibcode = 2011PNAS..10818009N|doi-access = free}}</ref> A live specimen was seen and recorded on video in November 2019 at {{Cvt|69|m}} off the village of [[Umzumbe]] on the South Coast of KwaZulu-Natal, {{Cvt|325|km}} south of the iSimangaliso Wetland Park. This is the farthest south since the original discovery, and the second shallowest record after {{Cvt|54|m}} in the [[Diepgat Canyon]]. These sightings suggest that they may live shallower than previously thought, at least at the southern end of their range, where colder, better-oxygenated water is available at shallower depths.<ref name="Fraser et al 2020" />

The geographical range of the Indonesia coelacanth, ''Latimeria menadoensis'', is believed to be off the coast of Manado Tua Island, [[Sulawesi]], Indonesia, in the [[Celebes Sea]].<ref name="ref3">{{cite journal |last1=Holder |first1=Mark T. |last2=Erdmann |first2=Mark V. |last3=Wilcox |first3=Thomas P. |last4=Caldwell |first4=Roy L. |last5=Hillis |first5=David M. |year=1999 |title=Two Living Species of Coelacanths? |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=96 |issue=22 |pages=12616–20 |bibcode=1999PNAS...9612616H |doi=10.1073/pnas.96.22.12616 |jstor=49396 |pmc=23015 |pmid=10535971 |doi-access=free}}</ref> Key components confining coelacanths to these areas are food and temperature restrictions, as well as ecological requirements such as caves and crevices that are well-suited for drift feeding.<ref name="ref11">{{cite journal |bibcode=1988NW.....75..149F |title=Habitat requirements of the living coelacanth ''Latimeria chalumnae'' at grande comore, Indian Ocean |last1=Fricke |first1=H. |last2=Plante |first2=R. |volume=75 |year=1988 |pages=149–51 |journal=Naturwissenschaften |doi=10.1007/BF00405310 |issue=3|s2cid=39620387 }}</ref> Teams of researchers using submersibles have recorded live sightings of the fish in the [[Celebes Sea|Sulawesi Sea]] as well as in the waters of [[Biak]] in [[Papua (province)|Papua]].<ref>{{cite web |url=http://theconversation.com/hunting-for-living-fossils-in-indonesian-waters-34770 |title=Hunting for living fossils in Indonesian waters|date=30 March 2015 |author=Augy Syaihailatua |work=The Conversation}}</ref><ref>{{cite journal |url=http://ir.nrf.ac.za/bitstream/handle/10907/374/Nulens_special_publication3.pdf?sequence=1 |archive-url=https://web.archive.org/web/20180818213827/http://ir.nrf.ac.za/bitstream/handle/10907/374/Nulens_special_publication3.pdf?sequence=1 |url-status=dead |archive-date=18 August 2018 |title=An updated inventory of all known specimens of the coelacanth, Latimeria spp.|author1=Rik Nulens |author2=Lucy Scott |author3=Marc Herbin |journal=Smithiana |date= 22 September 2011|page=2 }}</ref>

[[Anjouan]] Island and the [[Grande Comore]] provide ideal underwater cave habitats for coelacanths. The islands' underwater volcanic slopes, steeply eroded and covered in sand, house a system of caves and crevices which allow coelacanths resting places during the daylight hours. These islands support a large [[benthic]] fish population that helps to sustain coelacanth populations.<ref name="ref11" /><ref name="ref12" />

During the daytime, coelacanths rest in caves anywhere from {{Convert|100 to 500|m|sp=us}} deep. Others migrate to deeper waters.<ref name="ref10" /><ref name="ref1" />{{rp|37}} The cooler waters (below {{Convert|120|m|sp=us|disp=or}}) reduce the coelacanths' metabolic costs. Drifting toward reefs and night feeding saves vital energy.<ref name="ref11" /> Resting in caves during the day also saves energy that otherwise would be expended to fight currents.<ref name="ref12">{{cite journal |doi=10.1007/BF02028843 |title=Coelacanth ''Latimeria chalumnae'' aggregates in caves: First observations on their resting habitat and social behavior |year=1991 |last1=Fricke |first1=Hans |last2=Schauer |first2=Jürgen |last3=Hissmann |first3=Karen |last4=Kasang |first4=Lutz |last5=Plante |first5=Raphael |journal=Environmental Biology of Fishes |volume=30 |issue=3 |pages=281–6|bibcode=1991EnvBF..30..281F |s2cid=35672220 }}</ref>
[[File:Coelacanth1.JPG|thumb|upright|''Latimeria chalumnae'' model in the [[Oxford University Museum of Natural History]], showing the coloration in life]]

==Behavior==
Coelacanth locomotion is unique. To move around, they most commonly take advantage of up- or down-wellings of current and drift. Their paired fins stabilize movement through the water. While on the ocean floor, they do not use the paired fins for any kind of movement. Coelacanths generate thrust with their caudal fins for quick starts. Due to the abundance of its fins, the coelacanth has high maneuverability and can orient its body in almost any direction in the water. They have been seen doing headstands as well as swimming belly up. It is thought that the [[rostral organ]] helps give the coelacanth [[Electroreception and electrogenesis|electroreception]], which aids in movement around obstacles.<ref name="ref7" />

Coelacanths are fairly peaceful when encountering others of their kind. They do avoid body contact, however, withdrawing immediately if contact occurs. When approached by foreign potential predators (e.g. a submersible), they show panic flight reactions, suggesting that coelacanths are most likely prey to large deepwater predators. Shark bite marks have been seen on coelacanths; sharks are common in areas inhabited by coelacanths.<ref name="ref12" /> [[Electrophoresis]] testing of 14 coelacanth enzymes shows little genetic diversity between coelacanth populations. Among the fish that have been caught were about equal numbers of males and females.<ref name="ref1" />{{rp|38-40}} Population estimates range from 210 individuals per population to 500 per population.<ref name="ref1" />{{rp|39}}<ref name="ref13">{{cite journal |doi=10.1111/j.1523-1739.1998.97060.x |jstor=2387536 |title=Population Monitoring of the Coelacanth (''Latimeria chalumnae'') |year=2008 |last1=Hissmann |first1=Karen |last2=Fricke |first2=Hans |last3=Schauer |first3=Jürgen |journal=Conservation Biology |volume=12 |issue=4 |pages=759–65|s2cid=83504862 }}</ref> Because coelacanths have individual color markings, scientists think that they recognize other coelacanths via [[Electroreception and electrogenesis|electric communication]].<ref name="ref12" />

===Feeding===
Coelacanths are nocturnal [[piscivore]]s that feed mainly on [[Benthic zone|benthic]] smaller fish and various [[cephalopod]]s. They are "passive drift feeders", slowly drifting along currents with only minimal self-propulsion, eating whatever prey they encounter.<ref name="ref11" /><ref name="ref12" /> Coelacanths also use their rostral organ for its electroreception to be able to detect nearby prey in low light settings.<ref>{{Cite book |last=Bruton |first=Michael |title=The ecology and conservation of the coelacanth Latimeria chalumnae |publisher=Kluwer Academic Publishers |year=1991 |location=Netherlands |pages=313–339 |language=English}}</ref>

== Life cycle ==
[[File:Latimeria chalumnae embryo.jpg|thumb|''Latimeria chalumnae'' embryo with its yolk sac from the [[Muséum national d'histoire naturelle]]]]
[[File:Coelacanth_egg.jpg|thumb|upright=0.75|''Latimeria chalumnae'' egg]]
Coelacanths are [[ovoviviparous]], meaning that the female retains the fertilized eggs within her body while the embryos develop during a gestation period of five years. Typically, females are larger than the males; their scales and the skin folds around the [[cloaca]] differ. The male coelacanth has no distinct copulatory organs, just a cloaca, which has a [[Genital papilla|urogenital papilla]] surrounded by erectile [[Wattle (anatomy)|caruncles]]. It is hypothesized that the cloaca everts to serve as a copulatory organ.<ref name="ref1" />{{rp|27}}<ref name="ref2" />

Coelacanth eggs are large, with only a thin layer of membrane to protect them. Embryos hatch within the female and eventually are born alive, which is a rarity in fish. This was only discovered when the American Museum of Natural History dissected its first coelacanth specimen in 1975 and found it pregnant with five embryos.<ref>{{cite web|title = The Coelacanth: Five Fast Facts|url = http://www.amnh.org/explore/news-blogs/from-the-collections-posts/the-coelacanth-five-fast-facts|website = AMNH|access-date = 2015-10-28}}</ref> Young coelacanths resemble the adult, the main differences being an external yolk sac, larger eyes relative to body size and a more pronounced downward slope of the body. The juvenile coelacanth's broad yolk sac hangs below the pelvic fins. The scales and fins of the juvenile are completely matured; however, it does lack [[odontode]]s, which it gains during maturation.<ref name="ref2" />

A study that assessed the paternity of the embryos inside two coelacanth females indicated that each clutch was sired by a single male.<ref>{{Cite journal|title = Single-male paternity in coelacanths|journal = Nature Communications|volume = 4|page = 2488|doi = 10.1038/ncomms3488|pmid = 24048316|year = 2013|last1 = Lampert|first1 = Kathrin P.|last2 = Blassmann|first2 = Katrin|last3 = Hissmann|first3 = Karen|last4 = Schauer|first4 = Jürgen|last5 = Shunula|first5 = Peter|last6 = Kharousy|first6 = Zahor el|last7 = Ngatunga|first7 = Benjamin P.|last8 = Fricke|first8 = Hans|last9 = Schartl|first9 = Manfred|bibcode = 2013NatCo...4.2488L|url = http://oceanrep.geomar.de/22046/1/Lampert%20etal_coelacanth-paternity_NatureComms_2013.pdf}}</ref> This could mean that females mate [[monandrous]]ly, i.e. with one male only. [[Polyandry in nature|Polyandry]], female mating with multiple males, is common in both plants and animals and can be advantageous (e.g. insurance against mating with an infertile or incompatible mate), but also confers costs (increased risk of infection, danger of falling prey to predators, increased energy input when searching for new males).{{citation needed|date=December 2021}}

== Conservation ==
Because little is known about the coelacanth, the conservation status is difficult to characterize. According to Fricke et al. (1995), it is important to conserve the species. From 1988 to 1994, Fricke counted some 60 individuals of ''L.&nbsp;chalumnae'' on each dive. In 1995 that number dropped to 40. Even though this could be a result of natural population fluctuation, it also could be a result of [[overfishing]]. The [[IUCN]] currently classifies ''L.&nbsp;chalumnae'' as "[[critically endangered]]",<ref name=iucn_chal>{{cite iucn |author=Musick, J.A. |date=2000 |title=''Latimeria chalumnae'' |volume=2000 |page=e.T11375A3274618 |doi=10.2305/IUCN.UK.2000.RLTS.T11375A3274618.en |access-date=13 November 2021}}</ref> with a total population size of 500 or fewer individuals.<ref name="ref1" />{{rp|39}} ''L.&nbsp;menadoensis'' is considered [[vulnerable species|Vulnerable]], with a significantly larger population size (fewer than 10,000 individuals).<ref name=iucn_mel>{{cite iucn |author=Erdmann, M. |date=2008 |title=''Latimeria menadoensis'' |volume=2008 |page=e.T135484A4129545 |doi=10.2305/IUCN.UK.2008.RLTS.T135484A4129545.en |access-date=13 November 2021}}</ref>

The major threat towards the coelacanth is the accidental capture by fishing operations, especially commercial deep-sea [[trawling]].<ref>{{cite news |url=https://www.theguardian.com/environment/2006/jan/08/food.fishing |title=Dinosaur fish pushed to the brink by deep-sea trawlers |work=The Observer |date=7 January 2006 |first=Inigo |last=Gilmore}}</ref><ref>{{cite web|title = Coelacanth|url = http://www.animalplanet.com/tv-shows/river-monsters/fish-guide/coelacanth/|website = Animal Planet|access-date = 2015-10-29|date = 2012-08-27}}</ref> Coelacanths usually are caught when local fishermen are fishing for [[oilfish]]. Fishermen sometimes snag a coelacanth instead of an oilfish because they traditionally fish at night, when oilfish (and coelacanths) feed.
Before scientists became interested in coelacanths, they were thrown back into the water if caught. Now that they are recognized as important, fishermen trade them to scientists or other officials. Before the 1980s, this was a problem for coelacanth populations. In the 1980s, international aid gave fiberglass boats to the local fishermen, which moved fishing beyond the coelacanth territories into more productive waters. Since then, most of the motors on the boats failed, forcing the fishermen back into coelacanth territory and putting the species at risk again.<ref name="ref1" />{{rp|40}}<ref name="ref14">{{cite journal |bibcode=1995Natur.374..314F |title=Yet more danger for coelacanths |last1=Fricke |first1=Hans |last2=Hissmann |first2=Karen |last3=Schauer |first3=Jürgen |last4=Plante |first4=Raphael |volume=374 |year=1995 |pages=314–5 |journal=Nature |doi=10.1038/374314a0 |pmid=<!--none--> |issue=6520|s2cid=4282105 |doi-access=free }}</ref>

Methods to minimize the number of coelacanths caught include moving fishers away from the shore, using different laxatives and malarial salves to reduce the demand for oilfish, using coelacanth models to simulate live specimens, and increasing awareness of the need for conservation. In 1987 the Coelacanth Conservation Council advocated the conservation of coelacanths. The CCC has branches located in Comoros, South Africa, Canada, the United Kingdom, the U.S., Japan, and Germany. The agencies were established to help protect and encourage population growth of coelacanths.<ref name="ref1" />{{rp|40}}<ref name="auto">{{cite web|title = Endangered Species Act Status Review Report for the Coelacanth (Latimeria chalumnae) |url = http://www.nmfs.noaa.gov/pr/species/Status%20Reviews/coelacanth_sr_2014.pdf|archive-url = https://web.archive.org/web/20150907232943/http://www.nmfs.noaa.gov/pr/species/Status%20Reviews/coelacanth_sr_2014.pdf|archive-date = 2015-09-07|website = nmfs.noaa.gov|access-date = 2015-10-30|author=<!--staff writer-->}}</ref>

A "deep release kit" was developed in 2014 and distributed by private initiative, consisting of a weighted hook assembly that allows a fisherman to return an accidentally caught coelacanth to deep waters where the hook can be detached once it hits the seafloor. Conclusive reports about the effectiveness of this method are still pending.<ref>{{cite web|url=http://www.gpo.gov/fdsys/pkg/FR-2015-03-03/html/2015-04405.htm|title=Proposed Rule To List the Tanzanian DPS of African Coelacanth as Threatened Under the Endangered Species Act|publisher=NOOA (US)|access-date=30 October 2015}}</ref>

In 2002, the South African Coelacanth Conservation and Genome Resource Programme was launched to help further the studies and conservation of the coelacanth. This program focuses on biodiversity conservation, evolutionary biology, capacity building, and public understanding. The South African government committed to spending R10&nbsp;million on the program.<ref name="ref16">{{cite press release |title=South Africa announces plans for Coelacanth Programme |publisher=Science in Africa |date=February 2002 |url=http://scienceinafrica.com/south-africa-announces-plans-coelacanth-programme |access-date=19 April 2013 |archive-date=2 April 2015 |archive-url=https://web.archive.org/web/20150402191757/http://scienceinafrica.com/south-africa-announces-plans-coelacanth-programme |url-status=dead }}</ref><ref name="ref15">{{cite web |title=South African Coelacanth Conservation and Genome Resource Programme |publisher=African Conservation Foundation |url=http://www.wildnetafrica.org/explorer/item/south-african-coelacanth-conservation-and-genome-resource-programme?category_id=2545 |access-date=19 April 2013 |archive-url=https://web.archive.org/web/20150402155421/http://www.wildnetafrica.org/explorer/item/south-african-coelacanth-conservation-and-genome-resource-programme?category_id=2545 |archive-date=2 April 2015 |url-status=dead }}</ref> In 2011, a plan was made for a Tanga Coelacanth Marine Park to conserve biodiversity for marine animals including the coelacanth. The park was designed to reduce habitat destruction and improve prey availability for endangered species.<ref name="auto" />

<gallery widths="200px" heights="145px">
File:Coelacanth sea world.JPG|Coelacanth
File:Coelacanth in Kuwait by Prof Dr Norman Ali Khalaf July 2019.jpg|Coelacanth at Abdallah Al Salem Cultural Center in Kuwait
</gallery>

== Human consumption ==
Coelacanths are considered a poor source of food for humans and likely most other fish-eating animals. Coelacanth flesh has large amounts of oil, [[urea]], [[wax ester]]s, and other compounds that give the flesh a distinctly unpleasant flavor, make it difficult to digest, and can cause [[diarrhea]]. Their scales themselves secrete mucus, which combined with the excessive oil their bodies produce, make coelacanths a slimy food.<ref>{{Cite magazine|title = The Creature Feature: 10 Fun Facts About the Coelacanth|url = https://www.wired.com/2015/03/creature-feature-10-fun-facts-coelacanth/|magazine = Wired|access-date = 2015-10-30|date = 2015-03-02}}</ref> Where the coelacanth is more common, local fishermen avoid it because of its potential to sicken consumers.<ref>{{cite web |url=http://www.straightdope.com/columns/read/3029/know-any-good-recipes-for-endangered-prehistoric-fish-plus |title=Know any good recipes for endangered prehistoric fish? Plus: Do caribou like the Alaska oil pipeline? |publisher=[[The Straight Dope]] |first=Cecil |last=Adams |date=30 December 2011}}</ref> As a result, the coelacanth has no real commercial value apart from being coveted by museums and private collectors.<ref>{{cite book |author-link=Ross Piper |last=Piper |first=Ross |year=2007 |title=Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals |url=https://archive.org/details/extraordinaryani0000pipe |url-access=registration |publisher=[[Greenwood Press (publisher)|Greenwood Press]] |isbn=978-0-313-33922-6|page=249}}</ref>

==In culture==
Because of the surprising nature of the coelacanth's discovery, they have been a frequent source of inspiration in modern artwork, craftsmanship, and literature. At least 22 countries have depicted them on their postage stamps, particularly the Comoros, which has issued 12 different sets of coelacanth stamps. The coelacanth is also depicted on the 1000 [[Comorian franc]] banknote, as well as the 5 CF coin.<ref>{{cite book | last=Smith | first=J. L. B. | title=The Annotated Old Four legs | publisher=Struik Travel & Heritage | location=Cape Town | year=2017 | isbn=978-1-77584-501-0 | oclc=1100871937 |pages = 322–327}}</ref>

In the ''[[Pokémon]]'' media franchise, the [[List of Pokémon|Pokémon]] known as [[List of generation III Pokémon#Relicanth|Relicanth]] is based on the coelacanth.<ref>{{cite journal|first1=Augusto B.|last1=Mendes|first2=Felipe V.|last2=Guimarães|first3=Clara B. P.|last3=Eirado-Silva|first4=Edson P.|last4=Silva|year=2017|title=The ichthyological diversity of Pokémon|url=https://www.researchgate.net/publication/316888282|journal=Journal of Geek Studies|volume=4|issue=1|pages=39–67|access-date=12 July 2019|issn=2359-3024}}</ref><ref>{{cite web|url=https://www.discoverwildlife.com/animal-facts/pokemon-characters-real-wild-animals|title=20 Pokémon characters inspired by real wild animals|last=Williams|first=Leoma|date=24 May 2023|publisher=[[BBC Wildlife]]|access-date=10 December 2023}}</ref>

In the video game series ''[[Animal Crossing]]'', the coelacanth is a rare fish that can be caught by the player by fishing in the ocean.<ref>{{cite web|url=https://www.popsci.com/story/science/weirdest-thing-animal-crossing-coelacanth-plague-mask-green-blood/|title=Animal Crossing's most elusive fish has a bizarre real-life backstory|date=8 April 2020|work=[[Popular Science]]|access-date=10 December 2023}}</ref><ref>{{cite web|url=https://www.cbr.com/animal-crossing-rare-fish-guide/|title=Animal Crossing: How to Catch the Game's Rarest Fish|last=Nairn|first=Lacie|date=1 April 2020|website=[[Comic Book Resources]]|access-date=10 December 2023}}</ref>

== References ==
{{Reflist|2}}

== Further reading ==
* {{cite book|last=Bruton|first=Mike|title=When I Was a Fish: Tales of an Ichthyologist|publisher=Jacana Media(Pty)Ltd|year=2015}}
* {{cite magazine|title=Coelacanths – The Fish That Time Forgot|first=Hans|last=Fricke|magazine=[[National Geographic (magazine)|National Geographic]]|pages=824–838|volume=173|issue=6|date=June 1988|issn=0027-9358|oclc=643483454}}
* {{cite journal|last=Sepkoski |first=Jack |title=A compendium of fossil marine animal genera |journal=Bulletins of American Paleontology |volume=364 |page=560 |year=2002 |url=http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |access-date=2011-05-17 |url-status=dead |archive-url=https://web.archive.org/web/20090220223520/http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |archive-date=20 February 2009 }}
* {{cite book|last=Thomson|first=Keith S.|title=Living Fossil: the Story of the Coelacanth|publisher=W. W. Norton|year=1991}}
* {{cite news|last=Wade|first=Nicholas|url=https://www.nytimes.com/2013/04/18/science/coelacanth-dna-may-tell-how-fish-learned-to-walk.html|title=Fish's DNA May Explain How Fins Turned to Feet|newspaper=The New York Times|date=18 April 2013|pages=A3}}
* {{cite book|last=Weinberg|first=Samantha|title=A Fish Caught in Time: The Search for the Coelacanth|publisher=Fourth Estate|year=1999}}

== External links ==
{{Commons category|Coelacanthiformes}}
{{Wikispecies|Latimeria}}
* [https://www.pbs.org/wgbh/nova/fish/anatomy.html Anatomy of the coelacanth] by PBS ([[Adobe Flash]] required)
* [http://www.dinofish.com/ Dinofish.com] (requires a [[Frame (World Wide Web)|frame-capable browser]])
* {{cite web |first=Carolyn |last=Butler |title=Der Quastenflosser: Ein Fossil taucht auf |trans-title=The Coelacanth: A fossil turns up |language=de |url=http://www.nationalgeographic.de/reportagen/der-quastenflosser-ein-fossil-taucht-auf |work=National Geographic Deutschland |date=August 2012 |access-date=19 April 2013 |archive-date=3 February 2017 |archive-url=https://web.archive.org/web/20170203124532/http://www.nationalgeographic.de/reportagen/der-quastenflosser-ein-fossil-taucht-auf |url-status=dead }}
* [https://www.bbc.co.uk/news/science-environment-22184556 'Living fossil' coelacanth genome sequenced] BBC News Science & Environment; 17 April 2013

{{Sarcopterygii}}
{{Actinistia|state=collapsed}}
{{Diversity of fish}}
{{Evolution of fish|state=collapsed}}
{{Taxonbar|from1=Q59166|from2=Q2637499|from3=Q61881939}}
{{Authority control}}

[[Category:Coelacanthiformes| ]]
[[Category:Latimeriidae]]
[[Category:Live-bearing fish]]
[[Category:Ovoviviparous fish]]
[[Category:Fish of the Comoros]]
[[Category:Fish of Indonesia]]
[[Category:Fish of Kenya]]
[[Category:Fish of Mozambique]]
[[Category:Marine fish of South Africa]]
[[Category:Fish of Tanzania]]
[[Category:Extant Early Devonian first appearances]]
[[Category:1938 in biology]]