View source for Moray eel

{{Taxobox
| name = Moray eel
| image = Moray_eel.jpg
| image_width = 265px
| fossil_range = {{Fossil range|Late Miocene|Recent}}<ref name=FB>{{FishBase family|family=Muraenidae|year=2009|month=January}}</ref>
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Actinopterygii]]
| superordo = [[Elopomorpha]]
| ordo = [[Anguilliformes]]
| familia = '''Muraenidae'''
| subdivision_ranks = [[Genus|Genera]]
| subdivision = See text.
}}

'''Moray eels''' are large [[cosmopolitan (species)|cosmopolitan]] [[eel]]s of the [[family (biology)|family]] '''Muraenidae'''. There are approximately 200 species in 15 genera. The typical length of a moray is {{convert|1.5|m|ft}}. The longest is the [[slender giant moray]], ''Strophidon sathete'', at up to {{convert|4|m|ft}}. The largest in terms of total mass is the [[Giant moray]] (Gymnothorax javanicus), which reaches almost {{convert|3|m|ft}} and can weigh over {{convert|36|kg|lb}}.

== Anatomy ==
[[File:Muraena helena.2 - Aquarium Finisterrae edit.JPG|thumb|left|''[[Muraena helena]]'' showing typical moray eel morphology: robust anguilliform shape, lack of [[pectoral fin]]s and circular [[gill]] openings|alt=Photo of undulating moray on top of a coral colony]]
The [[dorsal fin]] extends from just behind the head along the back and joins seamlessly with the [[caudal fin|caudal]] and [[anal fin]]s. Most species lack [[pectoral fin|pectoral]] and [[pelvic fin]]s, adding to their snake-like appearance. Their eyes are rather small; morays rely on their highly developed sense of smell, lying in wait to ambush prey.

The body is generally patterned. [[Camouflage]] is also present inside the mouth. Their jaws are wide, framing a protruding snout. They possess large teeth, designed to tear flesh as opposed to holding or chewing.

[[File:Pharyngeal jaws of moray eels.svg|thumb|right|270px|Moray eel jaw anatomy|alt=Two diagrams of head and spine, one showing the pharyngeal jaw at rest; the other showing the jaws extended into the mouth]]
Moray eels' heads are too narrow to create the [[suction|negative pressure]] that most fish use to swallow prey.  Quite possibly because of this, they have a second set of jaws in their throat called [[pharyngeal jaws]], which also possess teeth. When feeding, morays launch these jaws into the mouth, where they grasp prey and transport it into the throat and  digestive system. Moray eels are the only  animal that uses pharyngeal jaws to actively capture and restrain prey.<ref name="Mehta2007">
{{cite journal 
| last =Mehtal | first =Rita S. 
| authorlink =Rita Mehtal 
| coauthors =Peter C. Wainwright 
| title =Raptorial jaws in the throat help moray eels swallow large prey 
| journal =[[Nature|Nature(journal)]] 
| volume =449 
| pages =79–82 
| date =[[2007-09-06]] 
| url =http://www.nature.com/nature/journal/v449/n7158/abs/nature06062.html 
| doi =10.1038/nature06062 
| accessdate =2007-09-06
}}</ref><ref name="Nature20070905">{{cite web 
| last =Hopkin | first =Michael 
| authorlink =Michael Hopkin 
| title =Eels imitate alien: Fearsome fish have protruding jaws in their throats to grab prey. 
| work =News 
| publisher =Nature.com 
| date =[[2007-09-05]] 
| url =http://www.nature.com/news/2007/070903/full/070903-11.html 
| doi =10.1038/news070903-11 
| accessdate =2007-09-06 
}}</ref><ref>[http://www.nsf.gov/news/news_summ.jsp?cntn_id=109985&org=NSF [[National Science Foundation]] (Sep. 5, 2007)]</ref>
Larger morays are capable of seriously wounding humans.

Morays secrete a protective mucus over their smooth, scaleless skin which in some species contains a toxin. Morays have much thicker skin and high densities of [[goblet cell]]s in the [[Epidermis (skin)|epidermis]] that allows mucus to be produced at a higher rate than in other eel species.  This allows sand granules to adhere to the sides of their burrows in sand-dwelling morays<ref>{{cite journal 
|author=Fishelson L 
|title=Skin morphology and cytology in marine eels adapted to different lifestyles 
|journal=Anat Rec. 
|volume=246 
|issue=1 
|pages=15–29 
|year=1996 |month=September 
|pmid=8876820 
|doi=10.1002/(SICI)1097-0185(199609)246:1<15::AID-AR3>3.0.CO;2-E 
}}</ref>, thus making the walls of the burrow more permanent due to the [[glycosylation]] of [[mucins]] in [[mucus]].  Their small circular [[gill]]s, located on the flanks far posterior to the mouth, require the moray to maintain a gap in order to facilitate respiration.

Morays are [[carnivorous]] and feed primarily on other [[fish]], [[cephalopod]]s, [[mollusk]]s, and [[crustacea]]ns. [[Grouper]]s, other morays, and [[barracuda]]s are among their few [[predator]]s.  There is a commercial fishery for several species, but some  cause [[ciguatera fish poisoning]]. Morays hide in [[reef]] crevices until their prey is close enough for capture. They then lunge out and clamp the prey in their strong [[jaw]]s.

== Behavior ==
=== Cooperative hunting ===
[[File:Lysmata amboinensis cleans mouth of a Moray eel.jpg|thumb|A [[Pacific cleaner shrimp]] cleans the mouth of a moray eel.|alt=Photo of eel with shrimp in its mouth]]
[[File:Ribbon eel.jpg|thumb|right|[[Ribbon moray]],<br />''[[Rhinomuraena quaesita]]''|alt=Photo of eel with head and neck protruding from sandy ocean bottom]]
A species of reef-associated [[grouper]], the roving coral grouper (''[[Plectropomus pessuliferus]]''), often recruits morays to aid them while hunting for food. This is the only known instance of interspecies cooperation among fish.<ref>In the December 2006 issue of the journal ''Public Library of Science Biology'', a team of [[biologist]]s announced the discovery of interspecies cooperative hunting involving morays. The biologists, who were engaged in a study of [[Red Sea]] [[cleaner fish]] (fish that enter the mouths of other fish to rid them of parasites), made the discovery.[http://www.livescience.com/animalworld/061207_fish_cooperation.html An Amazing First: Two Species Cooperate to Hunt | LiveScience<!-- Bot generated title -->]</ref><ref name=Bshary>{{cite journal |author=Bshary R, Hohner A, Ait-el-Djoudi K, Fricke H |title=Interspecific communicative and coordinated hunting between groupers and giant moray eels in the Red Sea |journal=PLoS Biol. |volume=4 |issue=12 |pages=e431 |year=2006 |month=Dec |pmid=17147471 |pmc=1750927 |doi=10.1371/journal.pbio.0040431 |url=http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0040431}}</ref>
[[File:Gymnothorax fimbriatus.JPG|thumb|left|[[Fimbriated moray]],<br />''[[Gymnothorax fimbriatus]]''|alt=Photo of eel in coral with wide open mouth]]

=== Reputation ===
The Morays have sometimes been described as vicious or ill-tempered.  Morays hide from humans and would rather flee than fight. Morays are shy and secretive, and attack humans only in [[self-defense]]. Most attacks involve accidental bites during human initiated interaction. Morays cannot see or hear very well and rely mostly on their acute sense of smell. Morays, however, ''do'' inflict a nasty bite, because, although not [[poison]]ous, their backward-pointing teeth are covered with [[bacteria]] which may infect the wound. 

Eels that have eaten certain types of toxic [[algae]] or fish that have eaten some of these algae, they can cause [[ciguatera fish poisoning]] if eaten.  Large morays can also cause extreme physical trauma, in some cases amputating a diver's finger.  Morays rest in crevices during the day and hunt [[nocturnal]]ly, although they may ensnare small fish and crustaceans that pass near them during the day.<ref name=Bshary/>
{{clearleft}}


== Habitat ==
Moray eels are [[Cosmopolitan distribution|cosmopolitan]], found in tropical and temperate seas, although they prefer subtropical [[coral reef]]s in warm waters. They live at depths up to {{convert|150|m|ft}}, where they spend most of their time concealed inside crevices and alcoves.

== Taxonomy ==
=== Genera ===
[[File:Moray eel kona.jpg|thumb|right|Whitemouth moray, ''[[Gymnothorax meleagris]]'']] 
* Subfamily ''[[Muraeninae]]''
** ''[[Cirrimaxilla]]''
** ''[[Echidna (genus)|Echidna]]'' 
** ''[[Enchelycore]]''
** ''[[Enchelynassa]]''
** ''[[Gymnomuraena]]'' 
** ''[[Gymnothorax]]''
** ''[[Monopenchelys]]''
** ''[[Muraena]]''
** ''[[Pseudechidna]]''
** ''[[Rhinomuraena]]''
** ''[[Scuticaria]]''
* Subfamily ''[[Uropteryginae]]''
** ''[[Anarchias]]''
** ''[[Channomuraena]]''
** ''[[Uropterygius]]''

== References ==
{{reflist}}

{{commonscat|Muraenidae}}

== External links ==
* [http://www.marbef.org/modules.php?name=News&file=article&sid=198 Moray Eels Grab Prey With ''Alien'' Jaws]


[[Category:Muraenidae]]

[[ar:حنكليس]]
[[ca:Murènid]]
[[cs:Murénovití]]
[[de:Muränen]]
[[es:Muraenidae]]
[[eo:Mureno]]
[[fr:Muraenidae]]
[[it:Muraenidae]]
[[lt:Mureninės]]
[[nl:Murenen]]
[[ja:ウツボ]]
[[no:Murene]]
[[pl:Murenowate]]
[[pt:Moreia]]
[[simple:Moray eel]]
[[su:Belut Moray]]
[[fi:Mureenat]]
[[sv:Muränor]]
[[zh:鯙科]]