Gulf torpedo

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Persian Gulf torpedo
Torpedo musandam.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Superorder: Batoidea
Order: Torpediniformes
Family: Torpedinidae
Genus: Torpedo
Species:
T. sinuspersici
Binomial name
Torpedo sinuspersici
Olfers, 1831
Torpedo sinuspersici rangemap.png
Range of the Gulf torpedo

The Gulf torpedo (Torpedo sinuspersici) or variable electric ray, is a species of electric ray in the family Torpedinidae. It is found in the Indian Ocean, but may represent a species flock of several local endemic species. [1] It is distinguishable from other Torpedo species in its range by its ornate dorsal coloration. [2] Another common name, marbled electric ray, is not to be confused with Torpedo marmorata .

Contents

Distribution and habitat

The Gulf torpedo is the most widespread of the electric rays in the western Indian Ocean, with a patchy range extending to South Africa, Somalia, the Red Sea, the Arabian Sea, the Persian Gulf, Sri Lanka, and the Andaman Sea. There are also less reliable reports of it occurring elsewhere, including Madagascar, the Seychelles, and the Laccadive Islands. [3] Recorded for the first time in 2002 in Mediterranean Sea, its presence needs to be clarified due to its strong resemblance with Torpedo marmorata , a species well established there. [4] It is found in shallow waters in sandy areas, on and near coral reefs, and offshore to a depth of 150 meters. [1] It often buries itself in the sandy bottom of gullies and estuaries. [2]

Description

The Gulf torpedo has a rounded pectoral fin disc, 84% as wide as long. The tail is short and stocky, bearing two small, subtriangular dorsal fins placed very close together, with the second three-quarters the size of the first. The pelvic fins are fleshy and partly fused to the disc, while the caudal fin is small and broadly rounded. The eyes are small; the spiracles are larger than the eyes in adults and bear 9-10 papillae on the rim. The skin is smooth. The mouth is wide and contains small, sharply cusped teeth. [2] [5] It measures up to 130 cm long, although most are less than 100 cm. [1] The angling record from South Africa is 13 kg. [2]

This species has distinctive dorsal coloration, composed of a base brown color with strong, thick cream or white vermiculations over the disc, pelvic fins, and tail, with many cream-colored irregular spots, no larger than eye diameter, on the anterior and lateral disc regions. However, the coloration varies somewhat within the species. Some specimens have cream-colored brain-shaped figures or rosettes over the disc and tail, becoming smaller towards the disc margins, along with small spots laterally on the disc and the front of the snout. [3]

Biology and ecology

The Gulf torpedo spends the day buried in sand. Marbled Torpedo Ray.JPG
The Gulf torpedo spends the day buried in sand.

Little is known of the life history of the Gulf torpedo. It is a sluggish predator of bony fishes. At night it actively hunts for food, sculling slowly through the water about a meter above the bottom; during the day it usually rests on the bottom and opportunistically ambushes unwary prey. It uses its broad pectoral fins to envelop the target fish before delivering an electric shock to stun it. [6] Usually solitary, they may form groups during the mating season. Reproduction is aplacental viviparous, with the developing embryos initially surviving on their yolk sacs, and then on enriched uterine fluid produced by the mother. [7] Litters of 9-22 young are birthed in the summer. [2] Newborns measure about 10 cm wide; males mature at a disc width of 39 cm and females at 45 cm. [6]

Human interactions

The Gulf torpedo may be threatened by habitat degradation, as well as being caught as bycatch in trawling fisheries. However, its conservation status is difficult to assess as the species may represent a flock of several local species. [1] It is often encountered by divers and can give a startling shock if molested. The flesh is edible and it is occasionally caught by shore anglers. Spear fishing for this species is illegal in Natal. [2]

Related Research Articles

<span class="mw-page-title-main">Torpedinidae</span> Family of cartilaginous fishes

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.

<i>Typhlonarke</i> Genus of cartilaginous fishes

Typhlonarke is a genus of sleeper ray in the family Narkidae, containing two poorly known species. The group is known for producing electric shocks for defense. Both species are deep-sea rays endemic to the waters off New Zealand. They are not to be confused with the blind electric rays of the genus Benthobatis.

<span class="mw-page-title-main">Pacific electric ray</span> Species of cartilaginous fish

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.

<span class="mw-page-title-main">Oval electric ray</span> Species of cartilaginous fish

The oval electric ray is a little-known species of sleeper ray in the family Narkidae. It is endemic to New Zealand, where it is generally found on the sea floor at a depth of 300–400 m (980–1,310 ft). Seldom exceeding 30 cm (12 in) in length, this species has a thick, oval pectoral fin disc and a short, stout tail with a single dorsal fin. It is blind, as its tiny eyes are covered by skin. Its pelvic fins are divided in two, with the anterior portion forming a limb-like appendage. These appendages likely allow the ray, which may not be able to swim at all, to "walk" along the bottom. The claspers of adult males extend beyond the disc. Polychaete worms are known to be part of its diet, and its reproduction is aplacental viviparous. It can produce an electric shock for defense. The International Union for Conservation of Nature presently lacks the data to assess its conservation status.

<i>Torpedo</i> (genus) Genus of cartilaginous fishes

Torpedo is a genus of rays, commonly known as electric rays, torpedo rays, or torpedoes. They are slow-moving bottom-dwellers capable of generating electricity as a defense and feeding mechanism.

<span class="mw-page-title-main">Ocellated electric ray</span> Species of cartilaginous fish

The ocellated electric ray or bullseye electric ray is a species of electric ray in the family Narcinidae, native to the shallow inshore waters of the eastern central Pacific from the Gulf of California to Ecuador. Reaching 25 cm (9.8 in) in length, this species has a rounded pectoral fin disc and pelvic fins with convex margins. Its short and thick tail bears two dorsal fins and terminates in a triangular caudal fin. The ocellated electric ray is named for the distinctive large eyespot on the middle of its disc, consisting of a black or yellow center surrounded by concentric rings. Its dorsal coloration is otherwise highly variable, ranging from plain to ornately patterned on a light to dark brown background. The front part of its disc is darker brown.

<span class="mw-page-title-main">Smooth butterfly ray</span> Species of fish

The smooth butterfly ray is a species of cartilaginous fish in the family Gymnuridae. It is a member of the order Myliobatiformes, which contains 10 total families. Its natural habitats are shallow seas, subtidal aquatic beds, estuarine waters, and coastal saline lagoons. Its common name is derived from its compressed body, pectoral fins that are wider than their length, and overall diamond shape.

<span class="mw-page-title-main">Coffin ray</span> Species of cartilaginous fish

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 Aden Gulf torpedo or Aden torpedo is a poorly known species of electric ray in the family Torpedinidae, seemingly endemic to the eastern Gulf of Aden, near the coast of Yemen. Growing to 41 cm (16 in) long, this species has a nearly circular pectoral fin disc and a short, thick tail with two dorsal fins and a well-developed caudal fin. It is characterized by its reddish dorsal coloration, which in contrast to related species lacks any additional markings. The International Union for Conservation of Nature (IUCN) has assessed the Aden Gulf torpedo as Endangered, citing its extremely small range and the intensive shrimp trawling that occurs in the region.

<span class="mw-page-title-main">Florida torpedo</span> Species of cartilaginous fish

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.

<span class="mw-page-title-main">Blackspotted torpedo</span> Species of cartilaginous fish

The black-spotted torpedo is a poorly known, uncommon species of electric ray in the family Torpedinidae, known for being capable of generating an electric shock. It is endemic to southern Africa and possibly several small Indian Ocean islands, although the latter reports may represent undescribed new species. Its appearance is similar to the Gulf torpedo, but it is duller in coloration.

<span class="mw-page-title-main">Marbled electric ray</span> Species of cartilaginous fish

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.

<span class="mw-page-title-main">Broad skate</span> Species of cartilaginous fish

The broad skate is a poorly known species of skate in the family Rajidae. It occurs at depths of 846 to 2,324 metres, and has been observed via remotely operated underwater vehicle by the Monterey Bay Aquarium Research Institute as deep as 3,167 metres (10,390 ft), making it one of the deepest-occurring skates known. It is sporadically distributed in the Pacific Ocean, from the Gulf of Panama to British Columbia and the Bering Sea, to the Tohoku Slope off northern Honshu and the Okhotsk Slope off Hokkaido. The species name, badia, comes from the Latin batius meaning "brown", referring to its color.

<span class="mw-page-title-main">Finless sleeper ray</span> Species of cartilaginous fish

The finless sleeper ray is a species of electric ray in the family Narkidae, and the sole member of its genus. It is found over the continental shelf of Southeast Asia from the eastern Andaman Sea to Vietnam and Borneo. Typically growing no more than 15 cm (5.9 in) long, it may be the smallest cartilaginous fish. The finless sleeper ray is the only electric ray that lacks dorsal fins. It has an oval pectoral fin disc that varies from longer than wide to wider than long, depending on age, and a short, robust tail that terminates in a short, deep caudal fin. The trailing margins of its pelvic fins are sexually dimorphic, being more concave in males.

<span class="mw-page-title-main">Common torpedo</span> Species of cartilaginous fish

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.

<i>Narcine entemedor</i> Species of cartilaginous fish

Narcine entemedor, the giant electric ray or Cortez electric ray, is a species of numbfish, family Narcinidae, native to the eastern Pacific Ocean from the Gulf of California to Panama. It is found in shallow water on sandy bottoms and sometimes adjacent to reefs. This species is closely related to the lesser electric ray from the western Atlantic, and may represent the same species. The specific epithet entemedor seems to be the Spanish equivalent of "intimidator".

<span class="mw-page-title-main">Atlantic torpedo</span> Species of cartilaginous fish

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.

<span class="mw-page-title-main">Blind electric ray</span> Species of cartilaginous fish

The blind electric ray is a little-known species of sleeper ray in the family Narkidae, endemic to New Zealand. It is found on the bottom, typically at a depth of 300–400 m (980–1,310 ft). Reaching 38 cm (15 in) in length, this species has a thin, nearly circular pectoral fin disc without visible eyes, and a short tail with a single dorsal fin. Its pelvic fins are divided in two, with the anterior portion forming a limb-like appendage; in males the claspers do not extend past the disc margin. A weak swimmer, the blind electric ray likely pushes itself along using its pelvic fins. It is known to feed on polychaete worms, and can defend itself with an electric shock. Reproduction is aplacental viviparous. The International Union for Conservation of Nature (IUCN) does not have enough information to assess the conservation status of this species.

<span class="mw-page-title-main">Japanese sleeper ray</span> Species of cartilaginous fish

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.

<span class="mw-page-title-main">Onefin electric ray</span> Species of cartilaginous fish

The onefin electric ray or Cape numbfish is a common but little-known species of electric ray in the family Narkidae, native to South Africa and Namibia. It is a benthic fish found in shallow coastal bays over sandy or muddy bottoms. This small species reaches 38 cm (15 in) in length, and has a nearly circular pectoral fin disc and a short, muscular tail that supports a large caudal fin. It can be identified by its single dorsal fin, which is located over the large pelvic fins. Its dorsal coloration is yellowish to dusky brown.

References

  1. 1 2 3 4 5 Kyne, P.M. (2019). "Torpedo sinuspersici". IUCN Red List of Threatened Species . 2019: e.T60136A140820271. doi: 10.2305/IUCN.UK.2019-3.RLTS.T60136A140820271.en . Retrieved 17 November 2021.
  2. 1 2 3 4 5 6 Van der Elst, R.; Borchert, P. (1997). A Guide to the Common Sea Fishes of Southern Africa. Struik. ISBN   1-86825-394-5.
  3. 1 2 de Carvalho, Marcelo R.; Stehmann, M.F.W.; Manilo, L.G. (2002). "Torpedo adenensis, a new species of electric ray from the Gulf of Aden, with comments on nominal species of Torpedo from the Western Indian Ocean, Arabian Sea, and adjacent areas (Chondrichthyes: Torpediniformes: Torpedinidae)". American Museum Novitates (3369): 1–34. doi:10.1206/0003-0082(2002)369<0001:TAANSO>2.0.CO;2. S2CID   198159708 . Retrieved 2008-10-09.
  4. Guide of Mediterranean Skates and Rays (Torpedo sinuspersici). Oct. 2022. Mendez L., Bacquet A. and F. Briand. http://www.ciesm.org/Guide/skatesandrays/torpedo-sinuspersici
  5. Randall, J.E.; Hoover, J.P. (1995). Coastal Fishes of Oman. University of Hawaii Press. ISBN   0-8248-1808-3.
  6. 1 2 Elaine Heemstra (2004). Coastal Fishes of Southern Africa. NISC (PTY) LTD. ISBN   1-920033-01-7.
  7. Froese, Rainer; Pauly, Daniel (eds.) (2008). "Torpedo sinuspersici" in FishBase . October 2008 version.