Himantura jenkinsii (lat.) Is a species of the genus of stingrays from the family of the caudate - tailed squad of the caudate-like superorder of rays . They live in the tropical waters of the Indian and western Pacific . They are found at a depth of up to 50 m. The maximum recorded disc width is 130 cm. The pectoral fins of these slopes fuse with the head, forming a diamond-shaped disc whose width exceeds the length. The snout is slightly pointed. The tail is longer than the disk. Dermal carinae absent. From the area around the eyes to the base of the tail lies a strip of heart-shaped scales. In the middle part are larger spear-shaped spikes. Coloring of the dorsal surface of the disc even yellow-brown. To the tail, the disk acquires a gray tint. The ventral surface is white.
| Himantura jenkinsii |
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| Scientific classification |
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| No rank : | Bilateral symmetrical |
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| International scientific name |
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Himantura jenkinsii ( Annandale , 1909) |
| Synonyms |
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- Trygon jenkinsii Annandale, 1909
- Himantura jenkinsi (Annandale, 1909)
- Dasyatis jenkinsii (Annandale, 1909)
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| Area |
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| Security status |
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Least ConcernedIUCN 3.1 Least Concern : 161744 |
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Like other tail-like Himantura jenkinsii breed by egg-production . Embryos develop in the womb, feeding on the yolk and histotroph. In litter 1-3 newborns. The diet of these stingrays consists mainly of crustaceans and small bony fish . They are the subject of targeted fishing. The meat is used for food, cartilage and skin are also valued [1] [2] .
Original image
Himantura jenkinsiiContent
For the first time, a new species was described on the basis of an individual with a disc 1 m wide, caught at a depth of 42–49 m near Ganjam , India , as Trygon jenkinsii . It was named after Dr. J. Travis Jenkins, scientific adviser on fisheries of the government of Bengal , who accompanied the expedition of the ship “Golden Crown”, during which the described instance was obtained [3] . These stingrays are often confused with Himantura fai .
Himantura jenkinsii is a species complex formed by Himantura toshi , Himantura astra , Himantura fai , seven-tufted stingray , Himantura leoparda , Himantura uarnak and Himantura undulata [4] .
In 1984, a stingray was described off the coast of South Africa, very similar in appearance to Himantura jenkinsii and differed only in the presence of spots on the rear edge of the disk. Similar spotted ramps are found in the Arafura Sea, in the Sulu Sea , in the waters of Sumatra and off the west coast of Sri Lanka . Leading taxonomists tentatively classified H. draco as the spotted morph Himantura jenkinsii [2] .
Himantura jenkinsii is widely, but unevenly distributed in the tropical waters of the Indo-Pacific region. They live off the southeast coast of Africa, including Madagascar , off the island of Socotra , in the waters of South and Southeast Asia , including the Philippines , New Guinea, and off the northern coast of Australia from Ningalu to Carpentaria Bay [2] [4] . These bottom fish are found offshore at a depth of up to 100 m, although they usually do not go deeper than 50 m. They prefer a sandy bottom. Swim in brackish water [2] [5] .
The dorsal surface of the disc of these stingrays is painted in an even yellow-brown color.
The pectoral fins of these slopes fuse together with the head, forming a diamond-shaped flat disk, whose width is 1.1-1.2 times greater than the length, the edges of the fins (“wings”) are widely rounded. The triangular snout forms an obtuse angle, its pointed tip protrudes beyond the edges of the disk. Behind the average size of the eyes are oval splashes that exceed them in size. On the ventral surface of the disk there are 5 pairs of gill slits, mouth and thin, long nostrils. Between the nostrils lies a flap of skin with a fringed lower edge. The mouth is curved in the form of an arc, 4 processes are present at the bottom of the oral cavity. Small blunt teeth are arranged in a checkerboard pattern and form a flat surface [4] [6] .
The ventral fins are small and rather narrow. The cylindrical tail, strongly thinning towards the tip, slightly exceeds the width of the disk. There are no skin folds on the caudal peduncle. On the dorsal surface in the central part of the caudal peduncle there is a thin spike connected by ducts to the poisonous gland. Sometimes stingrays have up to 3 spikes. Periodically, the spike breaks off and a new one grows in their place. The dorsal surface of the disc has a granular texture and is densely covered with tiny heart-shaped scales, which are located in a wide strip from the area between the eyes to the tail. In the central part of the disk are one or two rows of large spear-shaped spines. With the exception of spotted morphs, the dorsal surface of the disc is even yellow-brown in color. The tail behind the spike is gray. The ventral surface of the disc is white. The maximum recorded disk width is 150 cm, and the total length is 3 m [4] .
Himantura jenkinsii are found both singly and in groups. They observed segregation by sex [5] [7] . The basis of the diet of these rays are small bony fish, they also prey on crustaceans [2] [8] . In the waters of Mozambique, one individual of this species was observed in the accompanying Dasyatis microps [9] . The tapeworms Dollfusiella ocallaghani, Parachristianella baverstocki, P. indonesiensis, and Pterobothrium platycephalum parasitize these stingers [10] .
Himantura_jenkinsii on the beach. Maldives
Like other caudate-tailed Himantura jenkinsii belongs to ovoviviparous fish. Embryos develop in the womb, feeding on the yolk and histotroph . The disk width of newborns is 20–27 cm. In males, puberty occurs when a disk width of 75–85 cm is reached [2] [4] .
Himantura jenkinsii are the target fishing target. Because of the spectacular spines, their skin is much appreciated. In addition, they use meat and cartilage. These stingrays are mined using seines, bottom trawls, gill nets and tiers. They are caught as by- catch in the commercial sharktail fishery. Despite the lack of data, it is known that, in general, the number of these rays is decreasing. Off the northern coast of Australia, this species is relatively protected due to the mandatory use of devices that prevent the capture of sea turtles , therefore, in this region, the International Union for Conservation of Nature has assigned it the conservation status “Least Concerns”, while in Southeast Asia - “Vulnerable” [2] .
- ↑ Himantura jenkinsii in the FishBase database.
- ↑ 1 2 3 4 5 6 7 Himantura jenkinsii (English) . The IUCN Red List of Threatened Species .
- ↑ Annandale, N. (May 1909). Report on the fishes taken by the Bengal fisheries steamer "Golden Crown" Part I, Batoidei ". Memoirs of the Indian Museum 2 (1): 1-60.
- ↑ 1 2 3 4 5 Last, PR and JD Stevens. Sharks and Rays of Australia (second ed.). - Harvard University Press, 2009 .-- P. 440-441. - ISBN 0-674-03411-2 .
- ↑ 1 2 Hennemann, RM Sharks & Rays: Elasmobranch Guide of the World. - 2. - IKAN – Unterwasserarchiv, 2001. - S. 248. - ISBN 3-925919-33-3 .
- ↑ Randall, JE and JP Hoover. Coastal Fishes of Oman. - University of Hawaii Press, 1995. - S. 45. - ISBN 0-8248-1808-3 .
- ↑ White, W. Species and size compositions and reproductive biology of rays (Chondrichthyes, Batoidea) caught in target and non-target fisheries in eastern Indonesia // Journal of Fish Biology. - 2007. - Vol. 70, No. (6) . - P. 1809-1837. - DOI : 10.1111 / j.1095-8649.2007.01458.x .
- ↑ Fahmi. Diversity, Biology and Utilization of Chondrichthyans in West Central Indonesian Fisheries // {{{title}}}. - The University of Queensland: MPhil Thesis, Center for Marine Studies, 2007.
- ↑ Pierce, SJ, WT White and AD Marshall (2008). "New record of the smalleye stingray, Dasyatis microps ( Myliobatiformes: Dasyatidae ), from the western Indian Ocean." Zootaxa 1734: 65-68
- ↑ Campbell, RA and I. Beveridge. Oncomegas Aetobatidis Sp. Nov. (Cestoda: Trypanorhyncha), A Re-Description of O. Australiensis Toth, Campbell & Schmidt, 1992 and New Records of Trypanorhynch Cestodes from Australian Elasmobranch Fishes // Transactions of the Royal Society of South Australia. - 2009. - Vol. 133, No. (1) . - P. 18-29.
