Spiny butterfly ray
The spiny butterfly ray is a distinctive species of stingray known for its broad, bell-shaped body and short tail, which features a venomous spine not found in its smooth butterfly ray counterpart. Typically, this ray can grow to about 8.5 feet (2.5 meters) across, with some individuals near Africa reaching up to 13 feet (4 meters). Inhabiting the eastern and western Atlantic Ocean, these rays are often found near the seafloor in shallow bays or near coastlines, though they can also be spotted in schools farther offshore.
Their upper body is characterized by dark brown skin with hints of red or gray and occasional dark spots, while the underside is usually white or light brown. The spiny butterfly ray is a carnivore, preying on crustaceans, mollusks, and fish, and moves gracefully through the water thanks to its cartilaginous structure, akin to that of sharks. The species is ovoviviparous, meaning young rays are born live after a gestation period of four to nine months. Unfortunately, the spiny butterfly ray faces threats from predators and human activity and is currently classified as an endangered species, with a lifespan of up to 10 years. Caution is advised when interacting with these creatures due to their sharp spines, which can inflict painful injuries.
On this Page
Subject Terms
Spiny butterfly ray
The spiny butterfly ray's body is similar to that of the smooth butterfly ray. It is broad, bell-shaped, and has a short tail, but it has a poisonous spine on its tail which the smooth species does not have. The body of this stingray commonly grows to measure 8 1/2 feet (2 1/2 meters) across, although some near Africa have reportedly grown to be 13 feet (four meters) wide. The spiny butterfly ray can be found in the eastern and western Atlantic Ocean.
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Myliobatiformes
Family: Gymnuridae
Genus: Gymnura
Species: Altavela
The spiny butterfly ray can be found in areas of the Atlantic Ocean. The spiny butterfly ray most often swims near the bottom in shallow bays and near shorelines. Schools may occasionally appear farther offshore near the surface over deep water.
Like a large bell, the flattened body of this stingray species fans out from the pointed nose to the tips of its wing-like pectoral fins. The distance between fin tips may be as much as 8 1/2 feet (2 1/2 meters) in general, but some rays' bodies may reach 13 feet (four meters). The weights of spiny butterfly rays may reach 130 pounds (60 kilograms). Dark brown skin with a red or grayish tinge, sometimes with small, dark spots, covers the back and short tail of the butterfly ray. Its underside is white most often but may have light brown or rose shades.
Like other stingrays, the sharp, poisonous spine on the stingray's tail is a warning to stay away or to handle with care. Predators, intruding human beings, or those who catch and handle this creature must be very careful. Near the base and on the top surface of the tail, a long spine extends backward. Inside the spine are sacs containing poison, which sting painfully any animal or person it stabs. With its flexible tail acting like a whip, the stingray is able to defend itself quite well and can cause serious injury. Injury and poisoning from a stingray may result in death in some cases. It is not unusual for all or part of a spine to detach from the stingray. The stingray is then able to grow another one in its place.
The spiny butterfly ray is a carnivore, or meat-eating species. The diet of this species includes a wide variety of crustaceans, mollusks, and fish.
The spiny butterfly ray moves gracefully and quickly through the water with its flapping fins. The fins, as well as the rest of the body, do not contain any bones, but have cartilage instead. Cartilage is flexible but firm tissue like that which people have inside their ears and noses. Because it has cartilage and not bones, this species belongs to a group of fish called cartilaginous fish. This group also contains sharks.
The mating season for spiny butterfly rays occurs in late summer. Reproduction in the spiny butterfly ray is ovoviviparous. This means that the young are born live after hatching from eggs while still within their mother. After a gestation period (duration of pregnancy) of four to nine months, the two to six young rays feed on the egg sacs from which they hatched and then receive further nourishment from blood vessels inside their mother's womb. When they are large enough to be independent, they leave their mother's body and live on their own.
Predators of the spiny butterfly ray include large fish, sharks, and marine mammals. The spiny butterfly ray may live up to 10 years. They are an endangered species.
Bibliography
Conrath, Christina, and Rebecca Scarbrough. “Gymnura Altavela – Discover Fishes.” Florida Museum, 28 Dec. 2023, www.floridamuseum.ufl.edu/discover-fish/species-profiles/gymnura-altavela. Accessed 11 May 2024.
Smithsonian Tropical Research Institute. “Shorefishes - The Fishes.” Shorefishes - The Fishes - Species, 2023, biogeodb.stri.si.edu/caribbean/en/thefishes/species/2747. Accessed 11 May 2024.