Blackedge moray eel, ocellated moray eel, and blacktail moray eel
The Blackedge moray eel, Ocellated moray eel, and Blacktail moray eel are three species found in the western Atlantic Ocean, recognized for their distinctive spotted appearances. They inhabit seagrass beds and sandy to rocky areas at depths ranging from 30 to 400 feet, with the Blackedge and Ocellated morays typically residing in shallower waters. The Blackedge moray is the smallest of the trio, reaching about 20 inches, while the Blacktail can grow up to 30 inches long.
The Blackedge moray features dark brown backs with pale undersides and numerous pale spots, while the Ocellated moray is distinguished by its large, round black spots that resemble eyes. The Blacktail moray, on the other hand, has fewer large white spots and a characteristic black tail. These eels primarily feed on crustaceans and fish, and while they can exhibit aggressive behavior if threatened, they generally avoid interactions with humans. Reproduction occurs through spawning in offshore waters, leading to a larval stage known as leptocephali. In captivity, these eels can live up to 30 years and are not currently considered threatened.
On this Page
Subject Terms
Blackedge moray eel, ocellated moray eel, and blacktail moray eel
These three moray eels have in common their general location in the western Atlantic Ocean and the presence of spots on their bodies. They are members of the family of moray eels, a family whose members have a reputation for being large, strong, and vicious.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Anguilliformes
Family: Muraenidae
Genus: Gymnothorax
Species: Nigromarginatus (blackedge), Saxicola (ocellated), and Kolpos (blacktail)
Large numbers of blackedge and ocellated moray eels live in beds of seagrass and along sand and rock banks in water which is five to 50 fathoms deep, or 30 to 300 feet (10 to 19 meters) deep. In general, they stay outside of bays, and they do not make their homes in coral or rock reefs, as do several of the other moray eel species. Blacktail morays venture into water that may be up to 66 fathoms, or 400 feet (120 meters) deep. They inhabit the broad banks of sand and rock which lie offshore.
All three of these eels are between 1 1/2 and 2 1/2 feet (45 to 75 centimeters) long. The shortest of the three is the blackedge moray, which grows to be about 20 inches (50 centimeters) long. A full-grown ocellated moray is generally three to four inches (seven to 10 centimeters) longer than a blackedge at two feet (60 centimeters). The blacktail moray reaches a length of 30 inches (75 centimeters). Weights are not available for any of these three species.
Blackedge morays have dark brown backs and sides with pale undersides covered with many pale spots of a different shade. The pattern of these spots varies greatly between eels and depends also on where they live within the range. Sometimes blackedge morays also have faint dark lines near their gills. Their name comes from the black spots on their dorsal (back) and anal (rear) fins. The spots tend to merge into each other and to form black edges along the fins, particularly toward the caudal (tail) regions. More dark spots decorate the broad, flattened, pale heads, which also have large mouths with serrated, or jagged, teeth.
Ocellated morays are similar to the blackedge. While ocellated eels have large, black spots along the edges of their dorsal fins, their spots are separated and do not merge into each other as they do on blackedge morays. The name ocellated comes from these spots, which are round and look similar to eyes. Ocellus is from the Latin word oculus, which refers to the eye. Pale spots on the eels' belly form a net-like pattern. They also have black lines near their gills.
Blacktail moray eels also share several features in common with blackedge morays. They have black tails and only a few large, white spots on their bodies.
The diets of these eels include shrimp, crabs, lobsters, and other crustaceans, as well as fish and other creatures of the deep. They also eat other eels.
Natural predators include sharks, grouper, and barracudas. Like their other moray relatives, they can be quite vicious if disturbed or threatened by people. Most of the time, moray eels are not aggressive and leave people alone, but they may bite if divers come too close or stick their hands into the eels' caves.
Reproduction in these eels, as in others, occurs when the male and female spawn. Spawning is simply the female's releasing eggs into the water and the male's fertilizing them. This most often occurs in deep offshore water. The young eels hatch into a larval stage and are called leptocephali. Each leptocephalus resembles a slender, clear willow leaf. How long they are larvae is not certain, but it may be weeks or months before they change, or metamorphose, into the adult form. The adults do not raise the young.
Lifespans for these three moray may be up to 30 years in captivity. They are not a threatened species.
Bibliography
Bowling, Brenda. “Blacktail Moray, Gymnothorax Kolpos.” Texas Marine Species Identification, 2012, txmarspecies.tamug.edu/fishdetails.cfm?scinameID=Gymnothorax%20kolpos. Accessed 24 Mar. 2024.
Smithsonian Institution. “Shorefishes - The Fishes.” Shorefishes - The Fishes - Species, 2023, biogeodb.stri.si.edu/caribbean/en/thefishes/species/2800. Accessed 24 Mar. 2024.