Buzz
The marine species that inspired Ursula’s minions in Disney’s The Little Mermaid are uniquely strange, majestic, and perilous.
1. THEY FEATURE A DUAL JAW SYSTEM.
Zina Deretsky, Wikimedia Commons // CC BY 3.0
Similar to the creature in Alien (1979), morays ambush their prey using a concealed set of teeth. Hidden within their throat is a pair of pharyngeal jaws that assist the eel in capturing its meal. Unlike most predatory fish that use suction to draw food into their mouths, morays employ a two-phase approach. Initially, the outer jaws firmly seize the target. Then, their internal jaws spring forward, clamp onto the prey, and drag it into their digestive tract.
2. THERE ARE APPROXIMATELY 200 IDENTIFIED SPECIES.
The family is categorized into two primary groups: true morays and snake morays. The former are significantly more prevalent, with around 166 species currently identified. The key anatomical distinction lies in their fins—true morays have a dorsal fin that begins just behind their gills, while snake morays have this fin restricted to their tail area.
3. THE LARGEST SPECIMENS CAN WEIGH UP TO 66 POUNDS OR MORE.
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The largest species is fittingly called the giant moray (Gymnothorax javanicus). The biggest recorded specimens measure approximately 8 feet long and weigh 66 pounds, though unverified accounts suggest the existence of even larger 10-foot individuals. Divers have encountered these creatures in the Red Sea, along the eastern African coast, and across the Indo-Pacific region.
4. CERTAIN SPECIES POSSESS FLAT TEETH DESIGNED FOR CRUSHING HARD-SHELLED PREY.
While most morays have curved teeth perfect for catching fish, some species—such as the zebra moray (Gymnomuraena zebra)—feed on crabs, clams, mollusks, and sea urchins. Consuming such prey demands powerful jaws and specialized teeth for grinding, making their teeth notably flatter compared to other morays.
5. THE MAJORITY ARE NIGHT-DWELLERS.
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If you’re searching for morays, consider a nighttime dive. Generally, these eels become active after sunset, although a few species—like the chain moray, Echidna catenata—lead more daytime-oriented lives.
6. MORAYS OCCASIONALLY USE KNOTS TO FREE THEIR PREY.
When prey hides in a tight crevice, how does a moray retrieve it? Confronted with this challenge, the eel in the video above twists its tail into a knot. This knot moves along its body until it presses against the coral. With this leverage, the eel exerts additional force. This method not only helps morays extract prey from confined spaces but can also tear manageable pieces from larger victims.
7. THE GREEN MORAY (GYMNOTHORAX FUNEBRIS) IS ACTUALLY BROWN.
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The green appearance is an illusion caused by a protective mucus layer that many morays secrete to deter predators. This slime contains various toxins, including one that damages red blood cells. Additionally, the mucus alters the fish’s appearance. Despite being a dull brown, the yellowish tint of the mucus gives the green moray its vibrant look.
8. A THREATENING-LOOKING BEHAVIOR IS COMPLETELY HARMLESS.
When resting, a moray will rhythmically open and close its mouth. While this may seem like a warning to others, it’s actually a vital breathing mechanism. Unlike most fish, which use bony gill covers to force water over their gills, morays lack such structures. Instead, they must pump water through their mouths in large gulps to breathe.
9. THEIR DORSAL FIN IS A COMBINATION OF THREE SMALLER FINS.
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This feature combines the dorsal, caudal, and anal fins into what seems like a seamless, continuous structure.
10. OCCASIONALLY, GIANT MORAYS COLLABORATE WITH ANOTHER PREDATOR.
While the giant moray is a stealthy, slow-moving ambush predator, the roving coral grouper (Plectropomus pessuliferus), which shares its Red Sea habitat, is a fast swimmer built for pursuing prey in open waters. Despite their differences, these two predators occasionally team up.
Sometimes, a grouper will initiate a hunting expedition with a moray. After finding an eel, the grouper signals its interest with quick head movements. Together, their skills complement each other: the moray navigates the reef’s crevices while the grouper patrols above, leaving prey with no escape and ensuring a successful hunt.
