Muraena Helena

– Mediterranean Moray –

The Mediterranean moray (sometimes also called Roman eel, Common eel) is a fish of the moray eel family. It has a long eel-like body and is found in the eastern Atlantic Ocean and Mediterranean Sea. Its bite can be dangerous to humans.

The common moray eel lives on coastal cliffs with many crevices. She lives hidden in crevices, faults or even inside amphorae. It is found from the surface to a depth of about a hundred meters.

Description

The moray eel has a long serpentine body that can reach 1.50 m , robust and slightly compressed laterally especially in its posterior part. The head is short and has a domed profile. The mouth opens to the back of the eyeballs and has powerful jaws giving it a threatening and unfriendly appearance. The jaws have an anterior row of long teeth and, further back, small, conical, pointed teeth.
The moray eel does not have pectoral or ventral fins . The anal and dorsal fins merge into a rounded caudal fin that extends continuously from the gill openings to the posterior end of the body.
Its skin is smooth, thick and devoid of scales but covered with a protective mucus and facilitating movement. In adults, there is an area of ​​”crumpled” skin above the eyes.
Moray eels are generally dark brown in color , sometimes tinged with purple, and marbled with white and yellow (which can act as camouflage).
Its tubular nostrils protruding from the muzzle are clearly visible and provided with vibratile cilia which ensure the circulation of water on the olfactory nerve endings. Its soft and expandable opercula reveal small branchial openings.

Similar Species

Muraena helena can be confused with Gymnothorax unicolor (chocolate moray eel). Despite a similar appearance and fin constitution, the latter is generally smaller in size (up to 80 cm) and has a more rounded head. The brown moray eel, as the name suggests, has a uniformly brown colored body with a darker head.

A very close species is restricted to the archipelagos of the Canaries, the Azores or Madeira: Muraena augusti (Kaup, 1856). Its dark head has contrasting white eyes.

Muraena helena is also sometimes confused with the conger, Conger conger , which is found in the same biotopes * but which is nevertheless very different. The conger eel is greyish in color with a much more elongated head and characteristic thick-lipped jaw.

Alimentation

The moray eel is a nocturnal and territorial predator that remains hidden during the day. Poor swimmer, it usually hunts on the lookout in its lair while waiting for prey to pass nearby. It is particularly fond of octopus, squid and cuttlefish, but also consumes fish, crustaceans and possibly carrion.
Its nostrils with very sensitive taste buds give it a very developed sense of smell. The moray eel, being nearly blind, uses this infallible flair to spot prey and sharp teeth to capture and ingest them.
The moray eel has developed an original technique to be able to ingest prey that is too large: it twists its body to form a knot near its tail which it then slides towards its head. When the prey is properly placed and held, it throws its head back and can thus shred it.

Reproduction

The reproduction conditions of moray eels are still poorly understood to this day because of their nocturnal habits. They reproduce in summer (July to September) by depositing eggs about 5 mm in diameter which produce larvae * leptocephalus *, flattened, translucent and elongated oval shape. The larvae float and drift with the currents for about a year, then the moray eel descends to depth and becomes an active predator.

Associated Life

The moray eel is often seen in the company of Lysmata seticaudata , the Mediterranean barber shrimp, with which it has a commensal relationship *. This small crustacean feeds on the parasites present on the skin, in the respiratory openings and in the oral cavity of the moray eel and thus offers it a real cleansing.

Various Biology

Muraena helena is a territorial species that lives isolated. Despite her bad reputation, she is not aggressive. Rather fearful, she will only attack to defend herself if she feels threatened. It is therefore necessary to avoid disturbing it and approaching your hands with a crevice without having checked the nature of its occupants.
The bite can be dangerous, because the saliva contains secretions with digestive, hemolytic and neurotoxic action. In addition, there is superinfection due to rotting interdental food stains which slows healing.

Further Information

It is a species typical of rocky bottoms, which does not benefit from any legal protection status but which is increasingly rare, according to scuba divers. Its flesh, considered fine by some, makes it a species highly sought after by hunters since antiquity.

We often find a fanciful origin of his name referring to a wealthy Roman, Licinius Murena who would have owned huge pools in which lived tame moray eels who came to eat from his hand. According to this legend, he threw there the little obedient slaves, hence the uninviting reputation of the animal. It was more likely to be eels that the Romans kept in tanks (fresh water).

Appearance and Characteristics

The Mediterranean moray has an elongated, eel-like body and can reach a length of 1.5 meters and weigh over 15 kilograms. Its coloration varies from dark grey to dark brown with fine dark spots. The skin is slimy and without scales. The dorsal fin begins behind its head and continues to the caudal fin (fused with the anal fin). Pectoral fins are absent, teeth are long and sharp-pointed (like other morays), the mouth is long and robust and reaches behind the gills.

Ecology

The Mediterranean moray inhabits the coastal waters of the eastern Atlantic Ocean from the British Isles to the coast of Senegal; the waters of the Canary Islands and the Azores; and the Mediterranean Sea. It prefers rocky bottoms and lives in depths of from 16.5 to 264 feet (5 to 80 meters). It is a solitary and territorial species. The Mediterranean moray spends most of the day in cavities and clefts between rocks and is more active at night. It hunts fish, crayfish and cephalopods, but also feeds on dead animals.

The Mediterranean moray’s reproduction is not well known. They spawn about 60,000 eggs into open water, from which planktonic transparent leptocephali hatch.

One parasitic crustacean,^[2] the trematode Folliculovarium mediterraneum^[3] and the flatworm Lecithochirium grandiporum^[4] are parasites of the Mediterranean moray.

Human Importance

The bite of the Mediterranean moray can be dangerous mainly due to the mildly toxic slime of its skin. It can be utilized fresh and eaten broiled, boiled and baked. The skin can be used for leather.^[5]