The electric rays are a group of rays, flattened cartilaginous fish with enlarged pectoral fins, composing the order Torpediniformes. They are known for being capable of producing an electric discharge, ranging from 8 to 220 volts, depending on species, used to stun prey and for defense. There are 69 species in four families.
The family Torpedinidae contains 22 species of electric rays or torpedoes, flat cartilaginous fishes that produce electricity as a defense and feeding mechanism. They are slow-moving bottom-dwellers.
Demersal fish, also known as groundfish, live and feed on or near the bottom of seas or lakes. They occupy the sea floors and lake beds, which usually consist of mud, sand, gravel or rocks. In coastal waters they are found on or near the continental shelf, and in deep waters they are found on or near the continental slope or along the continental rise. They are not generally found in the deepest waters, such as abyssal depths or on the abyssal plain, but they can be found around seamounts and islands. The word demersal comes from the Latin demergere, which means to sink.
The leafscale gulper shark is a dogfish of the family Centrophoridae. C. squamosus is reported to have a lifespan of approximately 70 years, based on otolith ring counts. It was the first described species in the genus Centrophorus, which now contains 13 species.
Narcinidae, or numbfishes, are a family of electric rays. They are bottom-dwelling cartilaginous fishes with large, rounded pectoral fin discs and long tails. They can produce an electric discharge for defense, from which their scientific name is derived.
The sixgill stingray is a species of stingray and the only extant member of the family Hexatrygonidae. Although several species of sixgill stingrays have been described historically, they may represent variations in a single, widespread species. This flabby, heavy-bodied fish, described only in 1980, is unique among rays in having six pairs of gill slits rather than five. Growing up to 1.7 m (5.6 ft) long, it has a rounded pectoral fin disc and a long, triangular, and flexible snout filled with a gelatinous substance. It is brownish above and white below, and lacks dermal denticles.
Tetronarce californica also known as the Pacific electric ray is a species of electric ray in the family Torpedinidae, endemic to the coastal waters of the northeastern Pacific Ocean from Baja California to British Columbia. It generally inhabits sandy flats, rocky reefs, and kelp forests from the surface to a depth of 200 m (660 ft), but has also been known to make forays into the open ocean. Measuring up to 1.4 m (4.6 ft) long, this species has smooth-rimmed spiracles and a dark gray, slate, or brown dorsal coloration, sometimes with dark spots. Its body form is typical of the genus, with a rounded pectoral fin disc wider than long and a thick tail bearing two dorsal fins of unequal size and a well-developed caudal fin.
Epigonus telescopus, the black cardinal fish, is a species of deepwater cardinalfish found in most temperate oceans worldwide, at depths of between 75 and 1,200 metres though mostly between 300 and 800 metres. It can reach a length of 75 centimetres (30 in) TL though most specimens do not exceed 55 centimetres (22 in) TL. It has been reported that this species can reach an age of 104 years.
Hypnos monopterygius, also known as the coffin ray or Australian numbfish, is a species of electric ray endemic to Australia, where it is common in inshore waters shallower than 80 m (260 ft). It is the sole member of its genus Hypnos, and family Hypnidae. This small species typically reaches 40 cm (16 in) in length. Greatly enlarged pectoral fins and an extremely short tail, coupled with diminutive dorsal and caudal fins all concentrated towards the rear, give the coffin ray a distinctive pear-like shape. It is a varying shade of brown in color above, and has tiny eyes and a large, highly distensible mouth.
The Florida torpedo is a rare and little-known species of electric ray in the family Torpedinidae. It is known only from two specimens and a some wild sightings. Torpedoes have been recorded from three scattered locations in the Florida Straits and the western Caribbean Sea, and appear to inhabit coral habitats.
The marbled electric ray is a species of electric ray in the family Torpedinidae found in the coastal waters of the eastern Atlantic Ocean from the North Sea to South Africa. This benthic fish inhabits rocky reefs, seagrass beds, and sandy and muddy flats in shallow to moderately deep waters. It can survive in environments with very little dissolved oxygen, such as tidal pools. The marbled electric ray has a nearly circular pectoral fin disc and a muscular tail that bears two dorsal fins of nearly equal size and a large caudal fin. It can be identified by the long, finger-like projections on the rims of its spiracles, as well as by its dark brown mottled color pattern, though some individuals are plain-colored. Males and females typically reach 36–38 cm (14–15 in) and 55–61 cm (22–24 in) long respectively.
Variola, the lyretails, is a genus of marine ray-finned fish, groupers from the subfamily Epinephelinae, part of the family Serranidae, which also includes the anthias and sea basses. They are found in the tropical Indo-Pacific and their distribution extends from the Red Sea to South Africa across the Indian Ocean and east to the islands of the central Pacific.
Members of the family Narkidae are commonly known as sleeper rays. They are restricted to the temperate and tropical Indo-West Pacific from South Africa to Japan to Indonesia, and are exclusively marine and are absent from freshwater habitats. They occur from the intertidal zone to the continental shelf and the upper continental slope to a depth of 350 meters, favoring soft-bottomed habitats.
The common torpedo, also known as ocellate torpedo or eyed electric ray, is a species of electric ray in the family Torpedinidae. It is found in the Mediterranean Sea and the eastern Atlantic Ocean from the Bay of Biscay to Angola, and is a benthic fish typically encountered over soft substrates in fairly shallow, coastal waters. Growing to 60 cm (24 in) long, this species has a nearly circular pectoral fin disc and a short, thick tail with two dorsal fins of nearly equal size and a large caudal fin. It can be identified by the prominent blue spots on its back, which usually number five but may vary from zero to nine, as well as by the small knobs on the rims of its spiracles.
Assessor macneilli, the blue devilfish or blue scissortail, is a fish from the southwest Pacific Ocean. It occasionally makes its way into the aquarium trade. It grows to 6 centimetres (2.4 in) in length. It is purple-blue with long fins.
The Atlantic torpedo is a species of electric ray in the family Torpedinidae. It is found in the Atlantic Ocean, from Nova Scotia to Brazil in the west and from Scotland to West Africa and off southern Africa in the east, occurring at depths of up to 800 m (2,600 ft), and in the Mediterranean Sea. Younger individuals generally inhabit shallower, sandy or muddy habitats, whereas adults are more pelagic in nature and frequent open water. Up to 1.8 m (6 ft) long and weighing 90 kg (200 lb), the Atlantic torpedo is the largest known electric ray. Like other members of its genus, it has an almost circular pectoral fin disk with a nearly straight leading margin, and a robust tail with a large triangular caudal fin. Distinctive characteristics include its uniform dark color, smooth-rimmed spiracles, and two dorsal fins of unequal size.
Merluccius capensis is a ray-finned fish in the genus Merluccius, found in the south-eastern Atlantic Ocean, along the coast of South Africa. It is a long, lean fish with a large head, similar in appearance to the European hake and the deep-water Cape hake. By day, it lives close to the bottom on the continental shelf and upper slope at depths not usually exceeding 400 m (1,300 ft); it makes a large, daily vertical migration rising at night to feed in the nectonic zone, and it also migrates southwards in spring and northwards in autumn. It is an important commercial fish species in southern Africa.
The Japanese sleeper ray is a species of electric ray in the family Narkidae. It is common in the inshore and offshore waters of the northwestern Pacific Ocean from southern Japan to southern China. Growing up to 40 cm (16 in) long, the Japanese sleeper ray has a nearly circular pectoral fin disc colored reddish to chocolate brown above, sometimes with darker or lighter spots, and lighter brown below. The spiracles behind its small eyes have raised, smooth rims. Its short and muscular tail bears a single dorsal fin positioned aft of the rounded pelvic fins, and terminates in a large caudal fin.
The humpback red snapper, the paddletail, paddletail snapper or hunchback snapper, is a species of marine ray-finned fish, a snapper belonging to the family Lutjanidae. It has a wide Indo-West Pacific distribution. It is a commercially important species, as well as being sought after as a game fish. It is also a popular species for display in public aquaria. It has been reported to cause ciguatera poisoning.
The Spanish flag is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is part of the family Serranidae, which also includes the anthias and sea basses. It is found in the western Atlantic Ocean. It is the only species in the genus Gonioplectrus.
