Devil ray
Devil rays are a group of cartilaginous fish, closely related to manta rays, known for their distinctive horn-like cephalic fins near their mouths that aid in funneling food. They inhabit tropical and subtropical waters and primarily feed on plankton, crustaceans, and small fish. Characterized by their broad, diamond-shaped bodies, devil rays have large pectoral fins that resemble wings and a long, slender tail. The coloration typically features a black or blackish-brown dorsal surface with a lighter underside marked by black spots below the eyes.
These rays are social creatures that often swim in small groups and are known for their acrobatic behavior, leaping out of the water during mating displays. Many species of devil rays are considered endangered or threatened due to their slow reproductive rates, as it can take several years for them to reach maturity, and females give birth to only one pup every two to five years after a gestation period of 9 to 12 months. Despite their ominous name, devil rays pose no danger to humans, making them a fascinating subject for marine enthusiasts and conservationists alike.
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Devil ray
Devil ray species receive their name from the two horn-like, fleshy fins near their mouths. These fins funnel food into the ray's mouth. Devil rays are smaller than manta rays and elusive, making them difficult to study.
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Batiformes
Family: Mobulidae
Genus: Mobula
Species: Various (see below)
The devil ray belongs to the group of fish known as cartilaginous fish, which includes sharks and all skates and rays. These fish do not have skeletons of bones but of cartilage, the same firm, flexible tissue as in people's noses and ears.
Tropical and subtropical waters are home to the devil ray. Like the other manta rays, these rays feed on plankton, crustaceans, and small fish. Two fleshy fins, called cephalic fins, that look like horns, are located near its eyes and mouth. These fins funnel food into the mouth on the ray's underside. Inside the mouth, special gills filter food from the water and push the water out of the body. The location of the mouth is one difference between the larger manta rays and the devil ray.
As is characteristic of rays, the devil ray has a broad, flattened body in the shape of a diamond. Two large pectoral fins on either side of the head and body look like large, pointed wings. The distance between fin tips may be up to four feet (just over one meter). The ray's tail is long, slender, rounded, and whip-like, and it may be as long as the body. Black or blackish-brown skin covers the back of the ray, while white or gray covers its underside. A black spot sits just below each eye on the underside.
Devil rays usually swim in small groups. They may swim quickly and then fly from the water, gliding through the air before they land with a splash and loud smack. Smaller devil ray species, like the munk’s pygmy devil ray (Mobula munkiana), gather in large groups when mating and swim in a tub-like pattern. The group moves toward the surface and each ray leaps out of the water up to six feet (two meters).
Many devil ray species are endangered or threatened. Their breeding habits contribute to this issue. It takes several years for devil rays to reach sexual maturity. Pregnancies are 9 to 12 months long depending on the species and each female gives birth to one pup every two to five years. Before the young leaves its mother's body, it hatches from an egg inside her. The word for this type of birth is ovoviviparous. After birth, the baby ray feeds on its mother's milk-like liquid until it can eat solid foods.
Scientists estimate the life span of the devil ray is 10 to 15 years.
In spite of its name, the devil ray is not dangerous to humans.
Devil ray species include:
Atlantic pygmy devil ray Mobula hypostoma
Munk’s pygmy devil ray Mobula munkiana
Longhorned pygmy devil rays Mobula eregoodootenkee
Shorthorned pygmy devil rays Mobula kuhlii
Bentfin devil rays Mobula thurstoni
Spinetail devil rays Mobula japanica
Lesser Guinean Devil Ray Mobula rochebrunei
Giant Devil Ray Mobula mobular
Sicklefin or Chilean devil rays Mobula tarapacana
Bibliography
Boonstra, Roxane. "Mobula Hypostoma." FloridaMuseum, www.floridamuseum.ufl.edu/discover-fish/species-profiles/mobula-hypostoma. Accessed 5 Apr. 2024.
"Manta Ray." A-Z Animals, 2 Apr. 2023, a-z-animals.com/animals/manta-ray. Accessed 5 Apr. 2024.