Torpedo mackayana

Last updated

Torpedo mackayana
Torpedo mackayana CSP504-FD+1697847987.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. mackayana
Binomial name
Torpedo mackayana
Metzelaar, 1919

Torpedo mackayana, commonly known as the ringed torpedo, [2] Western African torpedo, [3] West African torpedo ray, [1] McKay electric ray, [4] or McKay's torpedo ray, [5] is an electric ray species in the family Torpedinidae, which lives in shallow waters on the western coast of Africa. Characterized by rounded spiracles and white and brown spots, females grow to 35–50 centimetres (14–20 in) and males to 31.5–38.2 centimetres (12.4–15.0 in).

Contents

Taxonomy

Torpedo mackayana was described in 1919 by Jan Metzelaar (1891–1929), a Dutch biologist. [2]

Etymology

The fish was named in honor of Donald Jacob Baron Mackay (1839-1921), the then colonial administrator and governor in India; he was one of the promoters of the 1904-1905 expedition that collected the type specimen in the Dutch West Indies. [6]


Description

Torpedo mackayana has a round, "fleshy" disc, which has a slightly greater width than length. It has a gray-brown or rusty-brown upperside and a white underside. [3] It is covered with small patches of brown or white. [4] These patches may differ significantly in size and distribution throughout its body. It has a long, strong tail and two dorsal fins. The first dorsal fin is broad, while the second is slightly smaller and more slender. Its teeth are distributed in up to 38 rows and it has visible flaps on its nostrils. It has rounded spiracles, a feature that does not appear in any other species in the genus Torpedo. [3]

Torpedo mackayana is a small to medium-sized ray. [3] Its growth and size was surveyed in the Coast of Senegal from 1994 to 1998, with the results having been published in 2001. This study showed that it has an average length of about 9.55 centimetres (3.76 in) and an average weight of 20.64 grams (0.728 oz) at birth. Females typically reach sexual maturity at about 35 centimetres (14 in) and males reach it at 31.5 centimetres (12.4 in). As an adult, females are larger than males. According to the survey, the length of adult females is 35–50 centimetres (14–20 in) and the length of adult males is 31.5–38.2 centimetres (12.4–15.0 in). The largest female observed weighed 2,010 grams (71 oz) and the largest male weighed 1,255 grams (44.3 oz). [5]

Ecology

The reproductive cycle of Torpedo mackayana can take a year, and gestation can take nearly half a year. Ovulation happens in May or June, and young are born in August or September. Like other species in the genus Torpedo, the oocyte of the species is sometimes prevented from growing until birth. Females have two uteri and two ovaries. The eggs of the species, when fertilized, weigh about 8.6 grams (0.30 oz) on average, and the oocytes weigh an average of 9.2 grams (0.32 oz). [5]

Torpedo mackayana has a coastal habitat and lives in depths of 30–50 metres (98–164 ft). [4] It has been found in estuaries and on sea floors of mud or sand. [1] Its prey consists of fish and smaller invertebrates. Little else is known about its biology. [3]

Distribution and conservation

Torpedo mackayana lives in tropical waters of the eastern Atlantic Ocean, [7] in 16 countries on the western coast of Africa. The most northern part of its range is Senegal, and the most southern part is Angola. It is likely caught by fisheries as a bycatch. Pollution and habitat destruction, due to coastal development, are also threats in part of its range. However, nothing is known about its population size or trend. [1] The adult population consists of more females than males, while young are more commonly male than female. [5] No conservation actions are taking place for the species, and it is listed on the IUCN Red List as Endangered. According to the IUCN, further research is required of the species' population before planning conservation actions. [1]

Related Research Articles

<span class="mw-page-title-main">Sergeant major (fish)</span> Species of fish

The sergeant major or píntano is a species of damselfish. It grows to a maximum length of about 22.9 centimetres (9.0 in).

<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">Barbeled houndshark</span> Species of shark

The barbeled houndshark is a species of ground shark and the only member of the family Leptochariidae. This demersal species is found in the coastal waters of the eastern Atlantic Ocean from Mauritania to Angola, at depths of 10–75 m (33–246 ft). It favors muddy habitats, particularly around river mouths. The barbeled houndshark is characterized by a very slender body, nasal barbels, long furrows at the corners of the mouth, and sexually dimorphic teeth. Its maximum known length is 82 cm (32 in).

<span class="mw-page-title-main">Atlantic weasel shark</span> Species of shark

The Atlantic weasel shark is a weasel shark of the family Hemigaleidae, found in the eastern Atlantic Ocean. Also known as the little tiger shark, it is the only species of the genus Paragaleus to have been recorded off the western coast of Africa. It is one of four species of small sharks within the carcharhinoid genus Paragaleus, including Paragaleus leucolomatus, Paragaleus tengi, and Paragaleus randalli. It also one of eight species within the weasel shark family, Hemigaleidae. It is currently considered by the International Union for Conservation of Nature (IUCN) as Endangered.

<span class="mw-page-title-main">Sawback angelshark</span> Species of shark

The sawback angelshark is an angelshark of the family Squatinidae It is one of rarest species of sharks known to date, and one of the three species of angelsharks that inhabits the Mediterranean. The Sawback angelshark lives in sandy and muddy bottoms of the ocean at depths of 30-500m.

<span class="mw-page-title-main">Scarlet-chested sunbird</span> Species of bird

The scarlet-chested sunbird is a species of bird in the family Nectariniidae. It is found in many areas of Sub-Saharan Africa, and from South Sudan to South Africa.

The speckled swellshark is a little-known species of catshark, and part of the family Scyliorhinidae, endemic to the waters off northwestern Australia. It occurs on the outer continental shelf and upper continental slope, at a depth of 150–455 m (492–1,493 ft). This species grows to 69 cm (27 in) long and has a stocky body and a short, broad, flattened head. As its common name suggests, its color pattern consists of many dark spots and white-spotted dark saddles and blotches on a light gray background. The juveniles are yellow with dark spots and lines, and a distinctive eyespot-like mark behind each eye. Like other swellsharks, this species can inflate itself as a defensive measure.

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

The smalleyed ray or smalleyed skate is a species of ray in the family Rajidae, the typical rays and skates, from the eastern Atlantic Ocean where it is found in tidal, coastal waters with sandy substrates.

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

The African wedgefish, guitarra, Lubbert's guitarfish, or spikenose wedgefish is a species of fish in the Rhinidae family. It is the only species in its genus to occur in the East Atlantic.

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">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">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.

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

The fanray is a species of ray in the family Platyrhinidae that lives in the western Pacific Ocean. It typically grows to a length of 30–50 centimetres (12–20 in) and a weight of 200–500 grams (7.1–17.6 oz), with a brown upperside and a white underside. It eats fish and crustaceans and has poor mobility. Males live to age five and females to age twelve, with both sexes maturing between two and five years. The species is found in China, Japan, Taiwan, Korea, Vietnam, and possibly Indonesia, in waters shallower than 100 metres (330 ft). It is probable that its population is declining due to being caught as a bycatch.

<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.

The flagtail swellshark is a little-known species of catshark, belonging to the family Scyliorhinidae, found at a depth of 480–700 m (1,570–2,300 ft) off northeastern Queensland, and possibly also nearby islands. This stout-bodied shark has a short, broad, and flattened head with a capacious mouth. Adults have a variegated brown coloration with 9–10 darker dorsal saddles and V-shaped blotch at the tip of the upper caudal fin lobe. Juveniles are yellow with narrow brown bars instead of saddles, and a distinctive marking between the spiracles shaped like two loops connected by a line. Like other swellsharks, this species can inflate its body when threatened.

<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.

The Diassanga mullet is a species of ray-finned fish, grey mullet from the family Mugilidae. It is found in the eastern Atlantic around the coasts of West Africa.

References

  1. 1 2 3 4 5 Jabado, R.W., Chartrain, E., De Bruyne, G., Derrick, D., Diop, M., Doherty, P., Dossa, J., Leurs, G.H.L., Metcalfe, K., Seidu, I., Soares, A.-L., Tamo, A., VanderWright, W.J. & Williams, A.B. (2021). "Torpedo mackayana (West African Torpedo Ray)". The IUCN Red List of Threatened Species .{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. 1 2 Watkins, Michael; Beolens, Bo (January 3, 2015). Sharks: An Eponym Dictionary. Pelagic Publishing Ltd. p. 106. ISBN   978-1784270377 . Retrieved 20 February 2019.
  3. 1 2 3 4 5 Last, Peter; Naylor, Gavin; Séret, Bernard; White, William; de Carvalho, Marcelo; Stehmann, Matthias (2016). Rays of the World. Csiro Publishing. p. 198. ISBN   978-0643109148 . Retrieved 20 February 2019.
  4. 1 2 3 Seret, Bernard (2006). Identification Guide of the Main Shark and Ray Species of the Eastern Tropical Atlantic: For the Purpose of the Fishery Observers and Biologists (PDF). FIBA. p. 55. ISBN   2951491492 . Retrieved 19 February 2019.
  5. 1 2 3 4 Capapé, Christian; Seck, A. A.; Diatta, Y.; Diop, Melissa (March 2001). "Observations on the reproductive biology of Torpedo (Tetronarce) mackayana (Torpedinidae), from the coast of Senegal (eastern tropical Atlantic)". Cybium. 1 (25): 95–99. Retrieved 19 February 2019.
  6. Christopher Scharpf & Kenneth J. Lazara (22 September 2018). "Order TORPEDINIFORMES". The ETYFish Project Fish Name Etymology Database. Christopher Scharpf and Kenneth J. Lazara. Archived from the original on 12 May 2016. Retrieved 21 January 2022.
  7. Carrier, Jeffrey C.; Musick, John A.; Heithaus, Michael R. (March 9, 2010). Sharks and Their Relatives II: Biodiversity, Adaptive Physiology, and Conservation (illustrated ed.). CRC Press. p. 225. ISBN   978-1420080483 . Retrieved 20 February 2019.