Description & Behavior
Green moray eels, Gymnothorax funebris (Ranzani, 1839), aka black moray, green cong, green conger, green congo, green eel, and olive-green moray eel, are one of the most common and one of the largest of the moray eels. These eels average 1.8 m in length, but can grow up to 2.5 m long and weigh up to 29 kg. The dark green to brown color comes from a yellowish mucous that covers its blue skin to provide protection from parasites and infectious bacteria. Additionally, they are often camouflaged to hide in the reef from unsuspecting prey. Camouflage often extends into the mouth which continually opens and closes slowly to move water over the gills for respiration. Their large mouth features strong, pointed sharp teeth. The body is muscular with a long dorsal fin that extends down the length of the body starting from the head and ending in a short tail fin.
World Range & Habitat
Green morays, Gymnothorax funebris, are found in the Western Atlantic: New Jersey (USA), Bermuda and northern Gulf of Mexico to Brazil. Recorded once from Nova Scotia, Canada. Eastern Atlantic and eastern Pacific.
A benthic (bottom dwelling) and solitary species found along rocky shorelines, reefs and mangroves. Depth ranges from 1-30 m. These eels can be territorial and have been known to occupy a specific reef for many years.
Feeding Behavior (Ecology)
Green morays are nocturnal predators with poor eyesight that primarily use their sense of smell to hunt for fish, squid, octopuses, crabs and occasionally other eels. Green morays have been observed eating octopuses whole as well as tentacle by tentacle.
Moray eels, like all true eels, are oviparous. Although little is known regarding green moray spawning, fecundity and early development of the leptocephali (see below), one published source records numerous ripe eggs measuring 1 mm in diameter from a 1.1 m female. In contrast to this single record other sources indicate a much larger size for the eggs of other morays, on the order of 3-4 mm in diameter.
True eels (Anguilliformes) along with the closely allied tarpon (Megalopidae), bonefish (Albulidae) and ladyfish (Elopidae) produce larvae known as leptocephali. These transparent, ribbon-like larvae drift among the plankton as they develop. Interestingly, muraenid leptocephali possess pectoral fins, a condition wholly different from that of the adults. It is during the transformation from leptocephalus to juvenile that the pectoral fins are reabsorbed.
Although the leptocephalus larvae of the green moray is undescribed, leptocephali of the various species of moray in general are distinguishable by patterns of pigment, the number of trunk muscles (known as myomeres), and the position of the dorsal fin and the anus.
Conservation Status & Comments
Due to its large size, the bites of this moray can be particularly dangerous, however unless provoked, this eel is not a threat to humans. Within their native range they are eaten by some indigenous peoples but the risk of contracting ciguatera poisoning from this species is considered great.
References & Further Research
Research Gymnothorax funebris @
Barcode of Life ~ BioOne ~ Biodiversity Heritage Library ~ CITES ~ Cornell Macaulay Library ~ Encyclopedia of Life (EOL) ~ ESA Online Journals ~ FishBase ~ Florida Museum of Natural History Ichthyology Department ~ GBIF ~ Google Scholar ~ ITIS ~ IUCN RedList (Threatened Status) ~ Marine Species Identification Portal ~ NCBI (PubMed, GenBank, etc.) ~ Ocean Biogeographic Information System ~ PLOS ~ SIRIS ~ Tree of Life Web Project ~ UNEP-WCMC Species Database ~ WoRMS