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Diseases and Parasites

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Poecilancistrum Infestation. Parasitic infestations (protozoa, worms, etc.)
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Allan Palacio
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Diseases and Parasites

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Disculiceps Infestation. Parasitic infestations (protozoa, worms, etc.)
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Allan Palacio
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Life Cycle

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Viviparous, placental (Ref. 50449). Distinct pairing with embrace (Ref. 205).
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Armi G. Torres
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Migration

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Amphidromous. Refers to fishes that regularly migrate between freshwater and the sea (in both directions), but not for the purpose of breeding, as in anadromous and catadromous species. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.Characteristic elements in amphidromy are: reproduction in fresh water, passage to sea by newly hatched larvae, a period of feeding and growing at sea usually a few months long, return to fresh water of well-grown juveniles, a further period of feeding and growing in fresh water, followed by reproduction there (Ref. 82692).
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Biology

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Biology poorly known. But its minute eyes suggest that it may be adapted to turbid water with poor visibility, as in large tropical rivers and muddy estuaries. Newborn specimens are from 56 to 61 cm long. Viviparous (Ref. 50449). Its notoriety may have stemmed from its widespread confusion with C. leucas. But this species is potentially dangerous as well because of its size and large teeth, though its reputation as a man-eater is still unproven.
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Importance

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fisheries: subsistence fisheries
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分布

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分布於印度-西太平洋區,包括孟加拉、印度、巴基斯坦、中國及臺灣等。臺灣東北海域曾捕獲過,極為罕見。
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臺灣魚類資料庫
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利用

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本物種已被列入國際自然保育聯盟(IUCN)紅皮書中物種受脅評估指標的"急危"狀態,亦即種群面臨即將絕滅的機率非常高。因此是屬於即刻需要保育的魚種。 
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描述

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體呈紡錘型,軀幹頗粗壯。頭寬扁。尾基上下方各具一凹窪。吻短而寬圓。眼小,圓形,眼眶後緣不具缺刻,瞬膜發達。前鼻瓣短而呈三角形;無口鼻溝或觸鬚。唇溝短,通常僅侷限於口角部位。口裂寬,弧形,下頜短,口閉時露齒;上頜齒寬扁三角形,邊緣具明顯鋸齒,齒尖稍外斜,無小齒尖;下頜齒較窄而直立,邊緣光滑。噴水孔缺如。背鰭2個,背鰭間無隆脊,第一背鰭寬大,起點與胸鰭基底中部後,後緣凹入,上角鈍尖,下角尖突;第二背鰭小,起點在臀鰭起點之後,後緣入凹,後角尖突;胸鰭大型,鐮刀形,後緣凹入,外角鈍圓,內角鈍圓,鰭端伸達第一背鰭基底後端;尾鰭寬長,尾椎軸上揚,下葉前部顯著三角形突出,中部低平延長,與後部間有一深缺刻,後部小三角形突出,尾端尖突。體背側灰褐色;腹側白色;體無任何色斑。各鰭暗褐色
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棲地

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本種生態習性所知有限,僅知棲息於沿岸、河口,甚至河川中。狹小的眼睛似乎是一種適應於能見度差的混濁河水中之特化。本種魚在恆河流域惡名昭彰,食人的傳言不斷,但這似乎只是人們對其巨大且鋒利的牙齒而感到恐懼的行為,因為食人之事不曾被証實過。
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Ganges shark

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The Ganges shark (Glyphis gangeticus) is a critically endangered species of requiem shark found in the Ganges River (Padma River) and the Brahmaputra River of Bangladesh and India. It is often confused with the more common bull shark (Carcharhinus leucas), which also inhabits the Ganges River and is sometimes incorrectly referred to as the Ganges shark.[3] Unlike bull sharks, which need to migrate to salt water to reproduce, species in the genus Glyphis are true river sharks. The genus is currently considered to contain three recent species; genetic evidence has shown that both the Borneo river shark (G. fowlerae) and Irrawaddy river shark (G. siamensis) should be regarded as synonyms of the Ganges shark, expanding the range of the species to Pakistan, Myanmar, Borneo, and Java. The species remains poorly known and very rare.

Taxonomy

Formerly the Borneo river shark (Glyphis fowlerae) and the Irrawaddy river shark (Glyphis siamensis) were considered to represent two other species in the genus Glyphis. They have recently been reclassified as G. gangeticus based on genetic studies, and their scientific names are treated as synonyms.[4]

The Borneo river shark is known only from the Kinabatangan River in Borneo. It can reach a length of 78 cm (31 in). Only 13 specimens are known to science, all collected in 1996. Expeditions in 2010 and 2011 failed to find any, and while fishermen recognised the shark, they have not been seen for many years.[4]

The Irrawaddy river shark is known only from a single museum specimen originally caught at the mouth of the Irrawaddy River in Myanmar, a brackish-water locality in a large, heavily silt-laden river lined with mangrove forests. It was collected in the 19th century and described as Carcharias siamensis by Austrian ichthyologist Franz Steindachner, in Annalen des Naturhistorischen Museums in Wien (volume 11, 1896).[5] However, subsequent authors doubted the validity of this species, regarding it as an abnormal bull shark (Carcharhinus leucas), until in 2005 shark systematist Leonard Compagno recognized it as distinct member of the genus Glyphis.[6] The specimen is a 60-cm-long immature male. It closely resembles the Ganges shark, but has more vertebrae (209 versus 169) and fewer teeth (29/29 versus 32–37/31–34).[6][7]

A possibly undescribed species of Glyphis is known from Mukah in Borneo, as well as Bangladesh. The status of a Borneo specimen from Sampit remains unclear.[4]

Physical appearance

G. gangeticus is a little-known species that is yet to be adequately described.[8] Its size at birth is 56 to 61 cm (22 to 24 in), growing to an estimated 178 cm (70 in) at maturity, with a maximum size of about 204 cm (80 in).[9] The size at birth or maturity is unknown for any other Glyphis species.[6]

A typical requiem shark in its external appearance, it is stocky, with two spineless dorsal fins and an anal fin. The first dorsal fin originates over the last third of the pectoral fins, with a free rear tip that is well in front of the pelvic fins. The second dorsal fin is relatively large, but much smaller than the first (about half the height). The anal fin is slightly smaller than the second dorsal fin and the pectoral fins are broad. A longitudinal upper precaudal pit is seen, but no interdorsal ridge. It is uniformly grey to brownish in color, with no discernible markings.[3]

Its snout is broadly rounded and much shorter than the width of its mouth. The mouth is long, broad, and extends back and up towards the eyes.[3]

Its eyes are minute, suggesting that it may be adapted to turbid water with poor visibility, such as occurs in the Ganges River and the Bay of Bengal. It has internal nictitating eyelids.[3]

The upper teeth have high, broad, serrated, triangular cusps and the labial furrows are very short. The lower front teeth have long, hooked, protruding cusps with unserrated cutting edges along the entire cusp, but without spear-like tips and with low cusplets on feet of crowns. The tooth row counts are 32–37/31–34.[10]

Diagnostic features

G. gangeticus can be identified by the first few lower front teeth, which have cutting edges along entire cusp, giving the cusps a claw-like shape, and low cusplets. Also, a second dorsal fin that is about half the height of first dorsal is distinct to this species.[11]

Distribution

The Ganges shark, as its name suggests, is largely restricted to the rivers of eastern and northeastern India, particularly the Hooghly River of West Bengal, and the Ganges, Brahmaputra, and Mahanadi in Bihar, Assam, and Odisha, respectively. It is typically found in the middle to lower reaches of a river.[12] One found in 2018 in a Mumbai fish market may have come from somewhere along the banks of the Arabian Sea.[13]

In theory, G. gangeticus could occur in shallow marine estuaries; however, no marine records of the species have been verified to date. Originally, the species was assigned a wide range in the Indo-West Pacific, but this was found to be mostly based on other species of requiem sharks, particularly members of the genus Carcharhinus.[9]

Most literature records and specimens labelled as this species are in fact bull sharks (Carcharhinus leucas) or other carcharhinid species. An extensive 10-year search produced only a few specimens, caught in 1996 in the Ganges River.[14]

Habitat and ecology

G. gangeticus is known to inhabit only freshwater, inshore marine, and estuarine systems in the lower reaches of the Ganges-Hooghly River system. Their feeding habits are mostly unknown. The shark's small eyes and slender teeth suggest that it is primarily a fish-eater and is adapted to turbid water.[3] With such limited visibility typical of many tropical rivers and estuaries, other senses − such as hearing, smell, and electroreception − are likely used for predation.[6] Because its eyes are tilted towards its back rather than to the sides or bottom (as is the case in most carcharhinids), the shark may swim along the bottom and scan the water above it for potential prey back-lit by the sun.[10] However, in the Bay of Bengal, G. gangeticus was found to feed heavily on dasyatid stingrays, which spend much of their time on the bottom.[15]

Reproduction

It is probably viviparous, with a yolk-sac placenta (speculation through analogy to related species of carcharhinids). The litter size and gestation period are unknown.[3] However, their life history cycle is probably similar to other river sharks, characterized by long gestation, slow growth, delayed maturity, and small litter size. These factors make the Ganges shark populations vulnerable to even relatively low levels of exploitation, such as sport angling or gill netting.[6]

Possibility of migration

Some researchers consider G. gangeticus to be amphidromous, covering more than 100 km in both directions.[16] However, this is not thought to be for breeding, as the case in anadromous and catadromous species.[17] The presence of newborn individuals in the Hooghly River suggests that the young may be born in fresh water.[11]

A specimen photographed in 2011 by natural history journalist Malaka Rodrigo at Negombo fish market in Sri Lanka prompted researcher Rex de Silva to speculate on whether the species could occasionally be carried south of its normal range by ocean currents. However, only the head of the shark appears in the photo. Leading shark expert Leonard Compagno emphasised the need to check the dentition and the dorsal fin proportions to confirm the specimen as G. gangeticus, stating that it could also be one of the four other named species.[18]

Specimens

G. gangeticus was originally known only from three 19th-century museum specimens, one each in the Muséum national d'histoire naturelle, Paris, Museum für Naturkunde, Berlin, and Zoological Survey of India, Calcutta.[19] No records exist between 1867 and 1996, and the 1996 records have not been confirmed as G. gangeticus. A specimen collected 84 km upstream of the mouth of the Hooghly River at Mahishadal in 2001 was identified as G. gangeticus, but on photographs of the jaw only.[10] If Carcharias murrayi (Günter, 1887) can be considered a junior synonym of this species, one was found near Karachi, Pakistan. However, the holotype was apparently lost or misplaced in the British Museum of Natural History.[3]

Molecular biology

Glyphis species, like other sharks, exhibit a very slow rate of genetic change. This makes them even more vulnerable to becoming extinct, as they are unable to adapt to the rapid and extreme changes caused by humans to their environment.[6]

As only a few specimens exist, naturally little material available is for genetic sampling. However, two websites list records for G. gangeticus:

The Barcode of Life Data Systems (BOLDS) Stats website[20] lists one record:
Public Records: 0
Specimens with Barcodes: 1
Species With Barcodes: 1

The NCBI Taxonomy database has one record of mitochondrial genetic material (1,044 base pairs of linear DNA):
Glyphis gangeticus bio-material GN2669,[21] reported in a 2012 paper on DNA sequencing in shark and ray species.[22]

Conservation

G. gangeticus is one of 20 sharks on the International Union for Conservation of Nature and Natural Resources Red List of endangered shark species. The species is currently classified as critically endangered. According to the organisation, less than 250 Ganges sharks are believed to exist. The need is urgent for a detailed survey of the shark fisheries of the Bay of Bengal.[2][3]

Major threats

River sharks are thought to be particularly vulnerable to habitat changes. The Ganges shark is restricted to a very narrow band of habitat that is heavily affected by human activity. Overfishing, habitat degradation from pollution, increasing river use, and management, including construction of dams and barrages, are the principal threats. Thought to be consumed locally for its meat, the Ganges shark is caught by gillnet, and its oil, along with that of the South Asian river dolphin, is highly sought after as a fish attractant.[23] It is also believed to be part of the Asian shark fin trade.[9] After a sighting in 2006, the species was not seen again for over a decade until one was found at a Mumbai fish market in 2016.[13]

The single Irrawaddy river shark specimen stems from an area of intensive artisanal fishing, mainly gillnetting, but also line and electrofishing. Habitat degradation may pose a further threat to this shark, including water pollution and the clearing of mangrove trees for fuel, construction materials, and other products. The shark may be naturally rare in this area and highly restricted in its range. Despite fishing and scientific surveys in the area, no more Irrawaddy river sharks have been recorded in the 100-plus years since the first.[24]

Conservation actions

In 2001, the Indian government banned the landing of all species of chondrichthyan fish in its ports. However, shortly afterwards, this ban was amended to cover only 10 species of chondrichthyans. These, including G. gangeticus, are protected under Schedule I, Part II A of the Wildlife Protection Act of India.[25] Doubt exists about the effectiveness of this measure, however, because of difficulties in enforcement. A widespread, albeit widely dispersed, artisanal fishery exists for both local consumption and international trade. Compagno (1997) recommends an in-depth survey of fishing camps and landing sites, along with a sampling program in the Ganges system to determine the current status of this shark along with other gangetic elasmobranchs such as stingrays and sawfish.[2]

Human interaction

The Ganges shark is widely feared as a ferocious man-eater,[26] but most of the attacks attributed to it are probably the result of confusion with the bull shark Carcharhinus leucas.[10] This is likely because bull sharks are known to travel long distances into freshwater systems and may co-exist in the same waters as the Ganges shark. Since little is known about the behaviour of genuine freshwater river sharks, and since G. gangeticus is critically endangered, contact with humans is very rare.[27]

The biological differences between the Ganges shark and bull shark also point to a lower likelihood of attacks on humans by the Ganges shark. G. gangeticus has much narrower, higher, upper teeth and slender-cusped, less heavily built lower teeth than C. leucas. Such small sharp teeth are more suitable for fish-impaling, and less useful for dismembering tough mammalian prey than the stout teeth of the bull shark.[11]

Etymology

Glyphis: from Greek glyphe, means "carving".[28]

See also

References

  1. ^ P. E. P, Deraniyagala (1969). "A Miocene vertebrate faunule from the Malu member of Ceylon". Spolia Zeylanica.
  2. ^ a b c Compagno, L.J.V. (2007). "Glyphis gangeticus". IUCN Red List of Threatened Species. 2007: e.T9281A12978210. doi:10.2305/IUCN.UK.2007.RLTS.T9281A12978210.en.{{cite journal}}: CS1 maint: uses authors parameter (link)
  3. ^ a b c d e f g h Compagno, L. J. V. (1997). "Threatened fishes of the world: Glyphis gangeticus (Muller & Henle, 1839) (Carcharnidae)". Environmental Biology of Fishes. 49 (4): 400. doi:10.1023/a:1007358922066. S2CID 35379347.
  4. ^ a b c Li, C.; Corrigan, S.; Yang, L.; Straube, N.; Harris, M.; Hofreiter, M.; White, W.T.; Naylor, G.J.P. (2015). "DNA capture reveals transoceanic gene flow in endangered river sharks". Proceedings of the National Academy of Sciences. 112 (43): 13302–13307. doi:10.1073/pnas.1508735112. PMC 4629339. PMID 26460025.
  5. ^ Froese, Rainer; Pauly, Daniel (eds.) (2009). "Glyphis siamensis" in FishBase. November 2009 version.
  6. ^ a b c d e f Martin, R. A. "The Mysterious, Endangered River Sharks (Glyphis spp.)". ReefQuest Centre for Shark Research. Retrieved 10 December 2012.
  7. ^ Compagno, L.J.V.; M. Dando & S. Fowler (2005). Sharks of the World. Princeton University Press. p. 309–311. ISBN 978-0-691-12072-0.
  8. ^ Martin, R. A. (2005). "Conservation of freshwater and euryhaline elasmobranchs: a review". Journal of the Marine Biological Association of the United Kingdom. 85 (5): 1049–1073. CiteSeerX 10.1.1.533.4292. doi:10.1017/s0025315405012105. S2CID 52833147.
  9. ^ a b c Compagno, L. J. V. (2005). 'Ganges shark Glyphis gangeticus'. In: Fowler, S.L., Cavanagh, R.D., Camhi, M., Burgess, G.H., Cailliet, G.M., Fordham, S.V., Simpfendorfer, C.A. and Musick, J.A. (eds). Sharks, rays and chimaeras: the status of the Chondrichthyan fishes. Gland, Switzerland, and Cambridge, UK.: IUCN Species Survival Commission Shark Specialist Group, IUCN. pp. 305–306.
  10. ^ a b c d Compagno, L. J. V. (1984). "FAO Species Catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 2 - Carcharhiniformes". FAO Fisheries Synopsis. 125 (4/2): 251–655. Retrieved 6 December 2012.
  11. ^ a b c "Glyphis gangeticus". Marine Species Identification Portal. Retrieved 6 December 2012.
  12. ^ "Glyphis gangeticus". Carnivora forum. Retrieved 6 December 2012.
  13. ^ a b Adamson, Allan (21 April 2018). "Rare River Shark Species Not Seen In A Decade Found On Sale In A Fish Market". Tech Times. Retrieved 22 April 2018.
  14. ^ Compagno, L. J. V. (2002). 'Freshwater and estuarine elasmobranch surveys in the Indo-Pacific region: threats, distribution and speciation'. In: S.L. Fowler, T.M. Reed and F.A. Dipper (eds) Elasmobranch Biodiversity, Conservation and Management; Proceedings of the International Seminar and Workshop, Sabah, Malaysia, July 1997. Gland, Switzerland and Cambridge, UK: IUCN SSC Shark Specialist Group.
  15. ^ Roberts, T. R. (2005). 'Debunking the mythology of the so-called freshwater shark of the Ganges. Glyphis gangeticus (Elasmobranchii, Carcharhinidae)'. In: 7th Indo-Pacific Fish Conference. Howard International Hotel, Taipei, Taiwan. Academica Sinica, Taipei, Taiwan. Taipei, Taiwan: Ichythological Society of Taiwan.
  16. ^ Hărșan, R.; Petrescu-Mag, I. V. (2008). "Endangered fish species of the world – a review". AACL Bioflux. 1 (2): 193–216.
  17. ^ Riede, K. (2004). 2004 Global register of migratory species - from global to regional scales. Final Report of the R&D-Projekt 808 05 081. Bonn, Germany: Federal Agency for Nature Conservation. p. 329.
  18. ^ de Silva, Rex I. (May–August 2011). "Does the Ganges shark Glyphis gangeticus stray to Sri Lanka?". Bombay Natural History Society. 108 (2): 136.
  19. ^ Baillie, Jonathan; Groombridge, Brian (1996). 1996 IUCN Red List of Threatened Animals. Gland, Switzerland: International Union for Conservation of Nature. ISBN 9782831703350.
  20. ^ "Glyphis gangeticus". Barcode of Life Data Systems. Retrieved 6 December 2012.
  21. ^ "Glyphis gangeticus". NCBI. 31 July 2012. Retrieved 10 December 2012. {{cite journal}}: Cite journal requires |journal= (help)
  22. ^ Naylor, G. J. P.; Caira, J. N.; Jensen, K.; Rosana, A. M.; White, W. T.; Last, P. R. (2012). "A DNA Sequence-Based Approach To the Identification of Shark and Ray Species and Its Implications for Global Elasmobranch Diversity and Parasitology". Bulletin of the American Museum of Natural History. 367: 1–262. doi:10.1206/754.1. hdl:2246/6183. S2CID 83264478.
  23. ^ Hoq, M. Enamul; Haroon, A. K. Yousuf; Hussain, M. G., eds. (January 2011). Shark fisheries in the Bay of Bengal, Bangladesh: Status and potentialities (PDF). Support to Sustainable Management of the BOBLME Project. Dhaka, Bangladesh: Bangladesh Fisheries Research Institute (BFRI). p. 76. ISBN 978-984-33-3276-9. Retrieved 12 October 2014.
  24. ^ Barnett, L.A.K.; K.L. Quaranta; D.A. Ebert; W.T. White & L.J.V. Compagno (2009). "Glyphis siamensis". The IUCN Red List of Threatened Species. 2009: e.T161611A5464198. doi:10.2305/IUCN.UK.2009-2.RLTS.T161611A5464198.en.
  25. ^ Schedule I, Part II A, Indian Wildlife Protection Act 1972. Government of India Ministry of Environment and Forests. 2006.
  26. ^ Coppleson, V. M. (1962). Shark Attack. Sydney, Australia: Angus and Robertson.
  27. ^ Courtenay, G.; Smith, D. R.; Gladstone, W. (2012). "Occupational health issues in marine freshwater research". Journal of Occupational Medicine and Toxicology. 7 (4): 4. doi:10.1186/1745-6673-7-4. PMC 3317851. PMID 22429712.
  28. ^ "Common names of Glyphis gangeticus". Fish base. Retrieved 10 December 2012.

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Ganges shark: Brief Summary

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The Ganges shark (Glyphis gangeticus) is a critically endangered species of requiem shark found in the Ganges River (Padma River) and the Brahmaputra River of Bangladesh and India. It is often confused with the more common bull shark (Carcharhinus leucas), which also inhabits the Ganges River and is sometimes incorrectly referred to as the Ganges shark. Unlike bull sharks, which need to migrate to salt water to reproduce, species in the genus Glyphis are true river sharks. The genus is currently considered to contain three recent species; genetic evidence has shown that both the Borneo river shark (G. fowlerae) and Irrawaddy river shark (G. siamensis) should be regarded as synonyms of the Ganges shark, expanding the range of the species to Pakistan, Myanmar, Borneo, and Java. The species remains poorly known and very rare.

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Requin du Gange

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Glyphis gangeticus

Le requin du Gange (Glyphis gangeticus) est une espère rare de requin d'eau douce vivant dans le Gange et dans l'estuaire du fleuve Hooghly. Le requin du Gange est l’un des seuls requins dotés d’osmorégulation (avec le requin bouledogue et à moindre mesure le requin taureau) et l’unique d’entre eux à vivre seulement en eaux douces. Il est extrêmement menacé et est présent sur le livret rouge de l’UICN. Il fait environ 2 m et se nourrit de petits poissons.

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갠지스상어

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Carcharias gangeticus by muller and henle.png

갠지스상어(학명:Glyphis gangeticus)는 흉상어목 흉상어과에 속하는 물고기이다. 몸길이는 1.78m로 상어에선 작은 편에 속한다.

특징과 먹이

갠지스상어는 모습이 전형적인 레퀴엠형 상어의 모습을 하고 있다. 몸의 옆줄을 기점으로 등쪽은 검은색을 띄며 배쪽은 흰색을 띈다. 영어권에서는 갠지스 샤크(Ganges Shark)라는 이름으로 불린다. 등지느러미는 2개이며 제1등지느러미는 가슴의 앞쪽에 위치하고 제2등지느러미는 꼬리지느러미와 가까운 곳에 위치한다. 또한 등지느러미와 항문지느러미가 함께 이어지며 제1등지느러미는 골반지느러미의 앞에 있는 무료 후면 팁으로 구성되고 가슴지느러미의 3분에 1의 크기가 된다. 제2등지느러미도 다른 흉상어과의 어류에 비해서 큰 편이며 항문지느러미는 제2등지느러미보다 약간 작고 가슴지느러미가 넓다. 세로 위에 전갑의 구덩이를 볼 수가 있지만 인터도르 산등성이는 없다. 그것은 눈에 띄는 표시가 없이 갈색회색으로 이뤄진다. 주둥이는 입의 너비보다 둥글고 넓으며 훨씬 짧은 특징이 있다. 입은 길고 넓으며 눈을 향해 앞뒤로 확장된 형태를 가진다. 이빨은 위턱과 아래턱에 총 14~16개를 가지고 있다. 위턱의 이빨은 높고 넓은 톱니의 모양을 가진 이빨이며 삼각형 자두와 음순의 고량을 가지고 있다. 아래턱의 이빨은 비교적 좁고 낮은 모양을 가지고 있다. 앞니의 아래는 길고 푹 튀어나온 커프스 전체에 따라 깍아입지 않은 절삭날이 있지만 창과 같은 팁이 없고 크라운 발에 커플릿이 낮다. 먹이로는 물고기갑각류, 양서류 등을 먹고 사는 육식성물고기에 속한다.

서식지와 보호활동

갠지스상어의 주요한 서식지는 갠지스강으로 담수해수를 오고가는 황소상어와는 달리 진정한 담수어인 민물 상어이다. 의 수심이 비교적 깊고 강의 유속이 느린 중류나 하류에서 주로 서식하는 어류이다. 갠지스상어는 갠지스강의 오염사람의 무분별한 남획 때문에 멸종위기에 처한 야생동·식물의 국제거래에 관한 협약을 통하여 보호를 받는 심각한 위급의 멸종위기종으로 인도에서 갠지스상어의 서식지를 보존하는 노력을 기울이고 있다.

같이 보기

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