The hooked-toothed big-eyed shark , or the Indian Ocean big-eyed shark , or the Malayan big-eyed shark [1] ( lat. Chaenogaleus macrostoma ) is the only species of the genus hooked-toothed big-eyed shark ( Chaenogaleus ) of the family of large-eyed sharks of the carchariformes . It lives in the Indian Ocean . It occurs at a depth of 59 m. Propagated by placental live birth . In the litter up to 4 newborns. The maximum fixed length is 150 cm, the maximum weight is 12 kg [2] . Color from light gray to bronze, without markings. The view is harmless to humans. These sharks are produced in a makeshift way. The meat is eaten [3] [4] .
| Big Tooth Shark |
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| Scientific classification |
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| No rank : | Bilateral symmetrical |
| Gender: | Hooked-toothed big-eyed sharks ( Chaenogaleus Gill , 1862 ) |
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| International scientific name |
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Chaenogaleus macrostoma
( Bleeker , 1852) |
| Synonyms |
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Hemigaleus macrostoma Bleeker, 1852 |
| Area |
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| Security status |
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Vulnerable speciesIUCN 3.1 Vulnerable : 161695 |
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Vintage image of a large-toothed big-eyed shark
Content
The species was first described in 1852 [5] . The holotype mentioned by Blecker was a male 69.9 cm long and was originally kept in the British Museum . Subsequently lost [6] . Probably, along with three representatives of the family of big-eyed sharks that live in Indo-Pakistani waters, the hooked-toothed big-eyed shark was mistakenly called Hemigaleus balfouri . In addition, this species is often confused with Hemipristis elongatus [7] .
Hooked-toothed big-eyed sharks live in the Indian Ocean, as well as in the northwestern and centralwestern Pacific Ocean - in the Persian Gulf , off the coast of Pakistan , India , Sri Lanka , Singapore , Thailand , Vietnam , China , Taiwan and Indonesia ( Java , Sulawesi ) [7] . They are found on the continental and island shelf to a depth of 59 m [3] .
The hook-toothed big-eyed sharks have a thin body and an elongated muzzle. Large oval eyes are elongated horizontally and equipped with blinking membranes . Behind the eyes there is tiny splatter . The gill slits are very long, 1.8β2.1 times the length of the eye. Mouth in the form of a long parabola . The length of the mouth is 66-82% of its width. The lower jaw is rounded on the symphysis. At the corners of the mouth there are labial grooves. Long and hooked lower teeth are visible even when the mouth is closed. The tip of each of the upper teeth is bent to the corner of the mouth and (only on this side) has lateral teeth; Notches are not present on either the lower or upper teeth. The first dorsal fin is rather large; its base lies between the bases of the pectoral and ventral fins. The second dorsal fin is 2/3 of the size of the first dorsal fin. Its base is located above the base of the anal fin. The anal fin is significantly smaller than both dorsal fins. The upper tip of the caudal fin has a small ventral notch. Color from light gray to bronze color without markings [8] [9] [10] .
Hooked-toothed big-eyed sharks reproduce by placental live birth. The length of newborns is about 20 cm. There are up to 4 newborns in a litter. The maximum fixed size is 150 cm with a weight of up to 12 kg [2] . Males reach puberty with a length of 83β97 cm. The diet probably consists of small bony fish , cephalopods, and crustaceans [7] .
On these sharks, cestodes Clistobothrium tumidum , Megalonchos mandleyi [11] , Pterobothrium heteracanthum and Pterobothrium sp. [12] .
The view is not dangerous to humans. These sharks are produced in a makeshift way off the coast of Sri Lanka and Pakistan. They are caught using bottom gill nets and tiers. The meat is eaten, fish meal is produced from waste. Fins due to their small size are not highly valued [13] . Intensive fishing is carried out in the area, the species is prone to overfishing. The International Union for Conservation of Nature has assigned this species a βVulnerableβ conservation status [4] .
- β Reshetnikov Yu.S. , Kotlyar A.N. , Russ T.S. , Shatunovsky M.I. The Bilingual Dictionary of Animal Names. Fish. Latin, Russian, English, German, French. / edited by Acad. V. E. Sokolova . - M .: Rus. Yaz., 1989 .-- P. 30 .-- 12,500 copies. - ISBN 5-200-00237-0 .
- β 1 2 Joshi, KK and Balachandran, K and Raje, S G. Changes in the shark fishery at Cochin. // Journal of the Marine Biological Association of India, 50 (1). - 2008 .-- S. 104 .
- β 1 2 Large-eyed Hooked Tooth Shark in the FishBase database.
- β 1 2 Chaenogaleus macrostoma (English) . The IUCN Red List of Threatened Species .
- β Bleeker P. 1852 Bijdrage tot de kennis der Plagiostomen van den Indischen Archipel. Initiations Africaines. III. Poissons de Mer du SΓ©nΓ©gal. v. 24 (art. 12): P. 1β92
- β http://shark-references.com (unopened) . Date of treatment November 24, 2012. Archived January 9, 2013.
- β 1 2 3 Compagno, Leonard JV 2. Carcharhiniformes // FAO species catalog. - Rome: Food and Agricultural Organization of the United Nations, 1984. - Vol. 4. Sharks of the World: An Annotated and Illustrated Catalog of Shark Species Known to Date. - P. 437β437. - ISBN 92-5-101383-7 .
- β Fowler, HW The fishes of the groups Elasmobranchii , Holocephali , Isospondyli , and Ostariophysi obtained by US Bureau of Fishing Steamer ALBATROSS // Bull.USNatl.Mus., 1. - 1941. - Vol. 100, No. (13). - P. 879.
- β Chen, JTF A review of the sharks of Taiwan // Biol.Bull.Dep.Biol.Coll.Sci.Tunghai Univ. (Lchthyol.Ser. 1). - 1963. - No. 19. - P. 102.
- β Compagno, LJV, 1979. Carcharhinoid sharks: morphology, systematics and phylogeny. Unpublished Ph. D. Thesis, Stanford University, P. 932 Available from University Microfilms International, Ann Arbor, Michigan
- β Southwell, T. On a collection of cestodes from marine fishes of Ceylon and India // Annals of Tropical Medicine and Parasitology. - 1927. - Vol. 21. - P. 351-373.
- β PALM, HW The Trypanorhyncha Diesing, 1863 .-- PKSPL-IPB Press, 2004 .-- ISBN 979-9336-39-2 .
- β White, WT, Last, PR, Stevens, JD, Yearsley, GK, Fahmi and Dharmadi. 2006. Economically Important Sharks and Rays of Indonesia. Australian Center for International Agricultural Research, Canberra, Australia
