Moray eel
Moray eel Temporal range: [1]
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Moray eel in the Maldives | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Anguilliformes |
Suborder: | Muraenoidei |
Family: | Muraenidae Rafinesque , 1810
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Subfamily | |
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Moray eels, or Muraenidae (
The English name, from the early 17th century, derives from Portuguese moréia, which itself derives from Latin mūrēna, in turn from Greek μύραινα, muraina; these are the Latin and Greek names of the Mediterranean moray.[3][4]
Anatomy
The
The body is generally patterned. In some species, the inside of the mouth is also patterned. Their jaws are wide, framing a protruding snout. Most possess large teeth used to tear flesh or grasp slippery prey. A relatively small number of species, for example the snowflake moray (Echidna nebulosa) and zebra moray (Gymnomuraena zebra), primarily feed on crustaceans and other hard-shelled animals, and they have blunt, molar-like teeth suitable for crushing.[6]
Morays secrete a protective
Jaw
The pharyngeal jaws of morays are located farther back in the head and closely resemble the oral jaws (complete with tiny "teeth"). When feeding, morays launch these jaws into the mouth cavity, where they grasp prey and transport it into the throat. Moray eels are the only known animals that use pharyngeal jaws to actively capture and restrain prey in this way.[8][9][10]
In addition to the presence of pharyngeal jaws, morays' mouth openings extend far back into the head, compared to fish which feed using suction. In the action of lunging at prey and biting down, water flows out the posterior side of the mouth opening, reducing waves in front of the eel which would otherwise displace prey. Thus, aggressive predation is still possible even with reduced bite times.[11] In at least one species, the California moray (Gymnothorax mordax), teeth in the roof of the mouth are able to fold down as prey slides backwards, thus preventing the teeth from breaking and maintaining a hold on prey as it is transported to the throat.
Differing shapes of the jaw and teeth reflect the respective diets of different species of moray eel. Evolving separately multiple times within the Muraenidae family, short, rounded jaws and molar-like teeth allow durophagous eels (e.g. zebra moray and genus Echidna) to consume crustaceans, while other piscivorous genera of Muraenidae have pointed jaws and longer teeth.[12][13][14] These morphological patterns carry over to teeth positioned on the pharyngeal jaw.[15][16]
Feeding-behavior
Morays are opportunistic,
Cooperative hunting
Reef-associated
Habitat
The moray eel can be found in both fresh and saltwater habitats. The vast majority of species are strictly marine, never entering freshwater. Of the few species known to live in freshwater, the most well-known is Gymnothorax polyuranodon.[25][26]
Within the marine realm, morays are found in shallow water nearshore areas, continental slopes, continental shelves, deep benthic habitats, and mesopelagic zones of the ocean, and in both tropical and temperate environments.[26] Tropical oceans are typically located near the equator, whereas temperate oceans are typically located away from the equator. Most species are found in tropical or subtropical environments, with only a few species (yellow moray) found in temperate ocean environments.
Although the moray eel can occupy both tropical oceans and temperate oceans, as well as both freshwater and saltwater, the majority of moray eels occupy warm saltwater environments, which contain reefs.[27] Within the tropical oceans and temperate oceans, the moray eel occupies shelters, such as dead patch reefs and coral rubble rocks, and less frequently occupies live coral reefs.[27]
Taxonomy
Genera
There are about 202 known species of moray eels, in 16 genera. These genera are in two sub-families, Muraeninae and Uropterygiinae, which are distinguished by the location of their fins.[28] In Muraeninae the dorsal fin is near the gill slits and runs down the back of the eel, and the anal fin is behind the anus.[28] In the Uropterygiinnae, both the dorsal and the anal fin are at the end of the tail.[28] Though this distinction can be seen between the two sub-families, there are still many varieties of genera within Muraeninae and Uropterygiinae. Of these, the genus Gymnothorax is by far the broadest, including more than half of the total number of species.
List of genera according to the World Register of Marine Species:
- Subfamily Muraeninae
- Genus Diaphenchelys— 1 species
- Genus Echidna — 11 species
- Genus Enchelycore — 13 species
- Genus Enchelynassa— 1 species
- Genus Gymnomuraena— 1 species
- Genus Gymnothorax — 125 species
- Genus Monopenchelys — 1 species
- Genus Muraena — 10 species
- Genus Pseudechidna— 1 species
- Genus Rhinomuraena— 1 species
- Genus Strophidon — 1 species
- Genus
- Subfamily Uropterygiinae
- Genus Anarchias — 11 species
- Genus Channomuraena — 2 species
- Genus Cirrimaxilla — 1 species
- Genus Scuticaria — 2 species
- Genus Uropterygius — 20 species
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Snowflake moray (Echidna nebulosa)
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Viper moray (Enchelynassa canina)
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Zebra moray (Gymnomuraena zebra)
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Laced moray (Gymnothorax favagineus)
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Monopenchelys acuta
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Mediterranean moray (Muraena helena)
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White ribbon eel (Pseudechidna brummeri)
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Ribbon eel (Rhinomuraena quaesita)
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Slender giant moray (Strophidon sathete)
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Kidako moray (Gymnothorax kidako)
Evolution
The moray eel's elongation is due to an increase in the number of vertebrae, rather than a lengthening of each individual vertebra or a substantial decrease in body depth.[29] Vertebrae have been added asynchronously between the pre-tail ("precaudal") and tail ("caudal") regions, unlike other groups of eels such as Ophicthids and Congrids.[30]
Relationship with humans
Aquarium trade
Several moray species are popular among aquarium hobbyists for their hardiness, flexible diets, and disease resistance. The most commonly traded species are the snowflake, zebra and goldentail moray (Gymnothorax miliaris). Several other species are occasionally seen, but are more difficult to obtain and can command a steep price on the market.[31]
Food poisoning
Moray eels, particularly the giant moray (Gymnothorax javanicus) and yellow-edged moray (G. flavimarginatus), are known to accumulate high levels of ciguatoxins, unlike other reef fish;[32][33] if consumed by humans, ciguatera fish poisoning may result. Ciguatera is characterised by neurological, gastrointestinal, and cardiovascular problems that may persist for days after eating tainted fish. In morays, the toxins are most concentrated in the liver.[33] In an especially remarkable instance, 57 people in the Northern Mariana Islands were poisoned after eating just the head and half of a cooked yellow-edged moray.[34] Thus, morays are not recommended for human consumption.
References
- ^ Froese, Rainer, and Daniel Pauly, eds. (2009). "Muraenidae" in FishBase. January 2009 version.
- ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Gymnothorax polyuranodon" in FishBase. January 2010 version.
- ^ "Moray - Definition of moray in English - Oxford Dictionaries". oxforddictionaries.com. Archived from the original on September 26, 2016. Retrieved 11 December 2016.
- ^ "moray". thefreedictionary.com. Retrieved 11 December 2016.; D'Arcy Wentworth Thompson, Glossary of Greek Fishes (London: Oxford University Press, 1947) pp. 162-165
- ^ "Moray Eels - Crazy Facts About the Moray Eel - Marine Life Guide". Khao Lak Liveaboard to Similan Islands. 2019-08-16. Retrieved 2021-06-17.
- ISBN 0-8248-2698-1
- PMID 8876820.
- S2CID 4384411.
- S2CID 85118599. Retrieved 2007-09-06.
- ^ "Moray Eels Are Uniquely Equipped to Pack Big Prey Into Their Narrow Bodies - NSF - National Science Foundation". Retrieved 11 December 2016.
- PMID 17234619.
- PMID 20674752.
- S2CID 19640346.
- S2CID 17433961.
- OCLC 30092375.
- OCLC 48892721.
- ^ Kooser, Amanda. "See a snowflake moray eel swallow a sushi snack in an extraordinary way". CNET. Retrieved 2021-06-17.
- S2CID 85897128.
- JSTOR 24321994.
- ^ June 2021, Mindy Weisberger-Senior Writer 10 (10 June 2021). "These eels can swallow prey on land, thanks to extendable jaws in their throats". livescience.com. Retrieved 2021-06-17.
{{cite web}}
: CS1 maint: numeric names: authors list (link) - ^ "Moray Eel - Facts and Beyond". Biology Dictionary. 2020-07-10. Retrieved 2021-06-17.
- ^ In the December 2006 issue of the journal Public Library of Science Biology, a team of biologists 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.An Amazing First: Two Species Cooperate to Hunt | LiveScience
- PMID 17147471.
- ^ Vail A.L., Manica A., Bshary R., Referential gestures in fish collaborative hunting, in Nature Communications, vol. 4, 2013.
- ISSN 0906-6691.
- ^ S2CID 7596020.
- ^ S2CID 85897128.
- ^ a b c Reece, Joshua (January 2010). "Phylogenetics and Phylogeography of Moray Eels (Muraenidae)". Washington University Open Scholarship.
- .
- PMID 21558261.
- ^ Maddox, Mike. "Morays!". TFH Magazine. Retrieved 2018-08-29.
- PMID 26787145.
- ^ PMID 28672845.
- PMID 14771403.
Further reading
- Gross, Miriam J.. The Moray Eel. United States: Rosen Publishing Group's PowerKids Press, 2005.
- Purser, Phillip. Keeping Moray Eels in Aquariums. United States: T.F.H., 2005.
- Didier, Dominique A.. Moray Eel. United States: Cherry Lake Publishing, 2014.
- Goldish, Meish. Moray Eel: Dangerous Teeth. United Kingdom: Bearport Publishing, 2009.
External links
- Moray Eels Grab Prey With Alien Jaws
- Smith, J.L.B. 1962. The moray eels of the Western Indian Ocean and the Red Sea. Ichthyological Bulletin; No. 23. Department of Ichthyology, Rhodes University, Grahamstown, South Africa.