গবলিন হাঙর: সংশোধিত সংস্করণের মধ্যে পার্থক্য

উইকিপিডিয়া, মুক্ত বিশ্বকোষ থেকে
পরবর্তী পার্থক্য →
বিষয়বস্তু বিয়োগ হয়েছে বিষয়বস্তু যোগ হয়েছে
দৃশ্যমানউইকিপাঠ্য
সোয়াইব (আলোচনা | অবদান)
৩৮০টি সম্পাদনা
নতুন পৃষ্ঠা: {{featured article}} {{taxobox | fossil_range = {{fossilrange|Holocene}} | status = LC | status_system = iucn3.1 | status_ref...
(কোনও পার্থক্য নেই)

১৬:১২, ১৭ ফেব্রুয়ারি ২০১৭ তারিখে সংশোধিত সংস্করণ

গবলিন হাঙর
সময়গত পরিসীমা: Holocene
বৈজ্ঞানিক শ্রেণীবিন্যাস
জগৎ: Animalia
পর্ব: Chordata
শ্রেণী: Chondrichthyes
উপশ্রেণী: Elasmobranchii
মহাবর্গ: Selachimorpha
বর্গ: Lamniformes
পরিবার: Mitsukurinidae
গণ: Mitsukurina
দ্বিপদী নাম
Mitsukurina owstoni
D. S. Jordan, 1898
Range of the Goblin shark[১]
প্রতিশব্দ

Odontaspis nasutus Bragança, 1904
Scapanorhynchus dofleini Engelhardt, 1912
Scapanorhynchus jordani Hussakof, 1909
Scapanorhynchus mitsukurii White, 1937

গবলিন হাঙর (Mitsukurina owstoni) গভীর-সমুদ্র হাঙরের একটি অপ্রতুল প্রজাতি। মাঝে মধ্যে বলা হয় "জীবন্ত জীবাশ্ম", it is the only extant representative of the family Mitsukurinidae, a lineage some 125 million years old. This pink-skinned animal has a distinctive profile with an elongated, flattened snout, and highly protrusible jaws containing prominent nail-like teeth. It is usually between ৩ এবং ৪ মি (১০ এবং ১৩ ফু) long when mature, though it can grow considerably larger. গবলিন হাঙরs inhabit upper continental slopes, submarine canyons, and সমুদ্রmounts throughout the world at depths greater than ১০০ মি (৩৩০ ফু), with adults found deeper than juveniles.

Various anatomical features of the গবলিন হাঙর, such as its flabby body and small fins, suggest that it is sluggish in nature. This প্রজাতি hunts for teleost fishes, cephalopods, and crustaceans both near the সমুদ্র floor and in the middle of the water column. Its long snout is covered with ampullae of Lorenzini that enable it to sense minute electric fields produced by nearby prey, which it can snatch up by rapidly extending its jaws. Small numbers of গবলিন হাঙরs are unintentionally caught by deepwater fisheries. The International Union for Conservation of Nature (IUCN) has assessed it as Least Concern, despite its rarity, citing its wide distribution and low incidence of capture.

শ্রেণীবিন্যাস

Differing jaw positions in preserved গবলিন হাঙরs led to several specimens being erroneously described as distinct প্রজাতি.

American ichthyologist David Starr Jordan described the গবলিন হাঙর in an 1898 issue of Proceedings of the California Academy of Sciences, recognizing the peculiar fish not only as a new প্রজাতি, but also a new genus and family. He based his account on an immature male ১০৭ সেমি (৪২ ইঞ্চি) long caught in Sagami Bay near Yokohama, Japan. The specimen had been acquired by shipmaster and naturalist Alan Owston, who had given it to Professor Kakichi Mitsukuri at the University of Tokyo, who in turn had brought it to Jordan. Thus, Jordan named the হাঙর Mitsukurina owstoni in honor of these two men.[২] The common name "গবলিন হাঙর" is a translation of its old Japanese name tenguzame, a tengu being a Japanese mythical creature often depicted with a long nose and red face.[৩] Another name for this প্রজাতি is elfin হাঙর.[১]

Shortly after Jordan's description was published, several scientists noted the similarity between Mitsukurina and the extinct Mesozoic হাঙর Scapanorhynchus.[৪] For a time, the prevailing view was to treat Mitsukurina as a junior synonym of Scapanorhynchus. Eventually, more complete fossils revealed many anatomical differences between Scapanorhynchus and Mitsukurina, leading modern authors to again regard them as distinct genera.[৫] Several গবলিন হাঙর specimens were described as separate প্রজাতি from 1904 to 1937, none of which are now considered valid. This taxonomic confusion arose because the specimens' jaws were fixed at varying degrees of protrusion during preservation, giving the appearance of proportional differences in the head.[৬]

জাতিজনি এবং বিবর্তন

Phylogenetic studies based on morphology have generally placed the গবলিন হাঙর as the most basal member of the order Lamniformes, known as mackerel হাঙরs.[৭][৮] Studies using genetic data have also supported a basal position for this প্রজাতি.[৯][১০] The family Mitsukurinidae, represented by Mitsukurina, Scapanorhynchus, and Anomotodon, dates back to the Aptian age of the Cretaceous period (c. 125–113 Ma). Mitsukurina itself first appears in the fossil record during the Middle Eocene (c. 49–37 Ma);[১১][১২] extinct প্রজাতি include M. lineata and M. maslinensis.[১৩][১৪] Striatolamia macrota, which lived in warm shallow waters during the Paleogene (c. 66–23 Ma), may also be a Mitsukurina প্রজাতি.[১৫] As the last member of an ancient lineage, and one that retains several "primitive" traits, the গবলিন হাঙর has been described as a "living fossil".[১৬]

বর্ণনা

The গবলিন হাঙর's jaws extend dramatically when feeding.

The গবলিন হাঙর has a distinctively long and flat snout, resembling a sword blade. The proportional length of the snout decreases with age.[১৭] The eyes are small and lack protective nictitating membranes; behind the eyes are spiracles. The large mouth is parabolic in shape. The jaws are highly protrusible and can be extended almost to the end of the snout, though normally they are held flush against the underside of the head. It has 35–53 upper and 31–62 lower tooth rows. The teeth in the main part of the jaws are long and narrow, particularly those near the symphysis (jaw midpoint), and are finely grooved lengthwise. The rear teeth near the corners of the jaw are small and have a flattened shape for crushing. Much individual variation in tooth length and width occurs, in whether the teeth have a smaller cusplet on each side of the main cusp, and in the presence of toothless gaps at the symphysis or between the main and rear teeth. The five pairs of gill slits are short, with the gill filaments inside partly exposed; the fifth pair is above the origin of the pectoral fins.[৩][৫][১৮]

The body is fairly slender and flabby. The two dorsal fins are similar in size and shape, both being small and rounded. The pectoral fins are also rather small and rounded. The pelvic and anal fins have long bases and are larger than the dorsal fins. The caudal peduncle is flattened from side-to-side and lacks keels or notches. The asymmetric caudal fin has a long upper lobe with a shallow ventral notch near the tip, and an indistinct lower lobe.[৫][১৮] The soft, semitranslucent skin has a rough texture from a covering of dermal denticles, each shaped like a short upright spine with lengthwise ridges. In life, this প্রজাতি is pink or tan due to visible blood vessels beneath the skin; the color deepens with age, and young হাঙরs may be almost white. The fins' margins are translucent gray or blue, and the eyes are black with bluish streaks in the iris. After death, the coloration quickly fades to dull gray or brown.[৩][৬] Adult হাঙরs usually measure between ৩ এবং ৪ মি (৯.৮ এবং ১৩.১ ফু) long.[৩] However, the capture of an enormous female estimated at ৫.৪–৬.২ মি (১৮–২০ ফু) long in 2000 showed this প্রজাতি can grow far larger than previously suspected.[১৭] The maximum weight on record is ২১০ কেজি (৪৬০ পা) for a 3.8-m-long হাঙর.[৫]

শব্দতত্ত্ব

The generic name honors Keigo Mitsukuri, a Japanese zoologist who studied at University College London during the 1860s. The specific name honors Alan Owston, an English collector of Asian wildlife.[১৯]

বিস্তৃতি এবং বাসস্থান

The গবলিন হাঙর has been caught in all three major oceans, indicating a wide global distribution. In the Atlantic Ocean, it has been recorded from the northern Gulf of Mexico, Suriname, French Guiana, and southern Brazil in the west, and France, Portugal, Madeira, and Senegal in the east.[১][৩][২০] It has also been collected from সমুদ্রmounts along the Mid-Atlantic Ridge.[২১][২২] In the Indo-Pacific and Oceania, it has been found off South Africa, Mozambique, Japan, Taiwan, Australia and New Zealand. A single eastern Pacific specimen is known, collected off southern California.[১][৩] This প্রজাতি is most often found over the upper continental slope at depths of ২৭০–৯৬০ মি (৮৯০–৩,১৫০ ফু).[৫] It has been caught as deep as ১,৩০০ মি (৪,৩০০ ফু), and a tooth has been found lodged in an underসমুদ্র cable at a depth of ১,৩৭০ মি (৪,৪৯০ ফু).[২৩] Adults inhabit greater depths than juveniles. Immature গবলিন হাঙরs frequent the submarine canyons off southern Japan at depths of ১০০–৩৫০ মি (৩৩০–১,১৫০ ফু), with individuals occasionally wandering into inshore waters as shallow as ৪০ মি (১৩০ ফু).[১][২৪] In April 2014, fishermen in Key West, Florida, while fishing in the Gulf of Mexico caught a গবলিন হাঙর in their fishing net, only the second one ever to be caught in the Gulf.[২৫] The হাঙর was photographed and released back into the water.[২৫]

In July 2014, a গবলিন হাঙর was found in a fishery net in Sri Lanka, reported in Valaichchenai eastern coastal line in Sri Lanka. The হাঙর was about ৪ ফু (১.২ মি) long and weighed about ৭.৫ কেজি (১৭ পা) The হাঙর was given to the NARA (National Aquatic Resource Reসমুদ্রrch & Development Agency) for further reসমুদ্রrch.[২৬]

জীববিজ্ঞান এবং বাস্তুতন্ত্র

Although observations of living গবলিন হাঙরs are scant, its anatomy suggests its lifestyle is inactive and sluggish. Its skeleton is reduced and poorly calcified, the muscle blocks along its sides (myomeres) are weakly developed, and its fins are soft and small. Its long caudal fin, held at a low angle, is also typical of a slow-swimming হাঙর. The long snout appears to have a sensory function, as it bears numerous ampullae of Lorenzini that can detect the weak electric fields produced by other animals. Due to the snout's softness, it is unlikely to be used for stirring up prey from the bottom as has been proposed.[৬] Vision seems to be less important than other senses, considering the relatively small optic tectum in the হাঙর's brain.[৩] Yet unlike most deep-সমুদ্র হাঙরs, it can change the size of its pupils, thus probably does use its sight in some situations.[২৩] গবলিন হাঙরs may fall prey to the blue হাঙর (Prionace glauca).[২৪] Parasites documented from this প্রজাতি include the copepod Echthrogaleus mitsukurinae,[২৭] and the tapeworms Litobothrium amsichensis and Marsupiobothrium gobelinus.[২৮]

খাওয়া

Rattails and other deep-living teleosts are the main food of the গবলিন হাঙর.

The গবলিন হাঙর feeds mainly on teleost fishes such as rattails and dragonfishes. It also consumes cephalopods and crustaceans, including decapods and isopods. Garbage has been recorded from the stomachs of some specimens.[২৯] Its known prey includes bottom-dwelling প্রজাতি such as the blackbelly rosefish (Helicolenus dactylopterus), and midwater প্রজাতি such as the squid Teuthowenia pellucida and the ostracod Macrocypridina castanea rotunda. Thus, the গবলিন হাঙর appears to forage for food both near the সমুদ্র floor and far above it.[৬][৩০]

Since it is not a fast swimmer, the গবলিন হাঙর may be an ambush predator. Its low-density flesh and large oily liver make it neutrally buoyant, allowing it to drift towards its prey with minimal motions so as to avoid detection.[২৪] Once prey comes into range, the হাঙর's specialized jaws can snap forward to capture it. The protrusion of the jaw is assisted by two pairs of elastic ligaments associated with the mandibular joint, which are pulled taut when the jaws are in their normal retracted position; when the হাঙর bites, the ligaments release their tension and essentially "catapult" the jaws forward.[৫] At the same time, the well-developed basihyal (analogous to a tongue) on the floor of the mouth drops, expanding the oral cavity and sucking in water and prey.[৬]

জীবন ইতিহাস

Little is known about গবলিন হাঙর reproduction because a pregnant female has yet to be found and studied. It likely shares the reproductive characteristics of other mackerel হাঙরs, which are viviparous with small litter sizes and embryos that grow during gestation by eating undeveloped eggs (oophagy).[১] The birth size is probably close to ৮২ সেমি (৩২ ইঞ্চি), the length of the smallest known specimen.[৩] Males mature sexually at about ২.৬ মি (৮.৫ ফু) long, while female maturation size is unknown.[১] No data is available on growth and aging.[৩]

মনুষ্য সংস্পর্শ

Given the depths at which it lives, the গবলিন হাঙর poses no danger to humans. A few specimens have been collected alive and brought to public aquariums, though they survived only a short time. One was kept at Tokai University and lived for a week, while another was kept at Tokyo সমুদ্র Life Park and lived for two days.[৫][৩১] Its economic significance is minimal; the meat may be dried and salted, while the jaws fetch high prices from collectors.[১][৫] At one time, the Japanese also used it for liver oil and fertilizer.[৩২] This হাঙর is not targeted by any fisheries, but is occasionally found as bycatch in bottom gillnets and trawls, hooked on longlines, or entangled in fishing gear. Most captures are isolated incidents; one of the few areas where it is caught regularly is off southern Japan, where around 30 individuals (mostly juveniles) are taken each year. A black scabbardfish (Aphanopus carbo) fishery off Madeira also takes two or three গবলিন হাঙরs annually. In April 2003, over a hundred গবলিন হাঙরs were caught off northwestern Taiwan; the cause of the event was unknown, though observers noted it was preceded by a major earthquake. The প্রজাতি had never been recorded in the area before, nor has it been found in such numbers since.[১][৩] The International Union for Conservation of Nature (IUCN) has listed the গবলিন হাঙর under Least Concern. In addition to its wide range, most of its population is thought to reside in unfished environments because few adults are caught. Therefore, it is not believed to be threatened by human activity.[১]

তথ্য সুত্র

  1. ↑ ক খ গ ঘ ঙ চ ছ জ ঝ ঞ ট "Mitsukurina owstoni"। বিপদগ্রস্ত প্রজাতির আইইউসিএন লাল তালিকা। সংস্করণ 2012.2। প্রকৃতি সংরক্ষণের জন্য আন্তর্জাতিক ইউনিয়ন। ২০০৪। 
  2. ↑ Jordan, D.S. (১৮৯৮)। "Description of a প্রজাতি of fish (Mitsukurina owstoni) from Japan, the type of a distinct family of lamnoid হাঙরs"। Proceedings of the California Academy of Sciences (Series 3) Zoology। 1 (6): 199–204। 
  3. ↑ ক খ গ ঘ ঙ চ ছ জ ঝ ঞ Castro, J.H. (২০১১)। The হাঙরs of North America। Oxford University Press। পৃষ্ঠা 202–205। আইএসবিএন 978-0-19-539294-4। 
  4. ↑ Hussakof, L. (১৯০৯)। "A new গবলিন হাঙর, Scapanorhynchus jordani, from Japan"। Bulletin of the American Museum of Natural History। 26: 257–262। 
  5. ↑ ক খ গ ঘ ঙ চ ছ জ Compagno, L.J.V. (২০০২)। হাঙরs of the World: An Annotated and Illustrated Catalogue of হাঙর প্রজাতি Known to Date (Volume 2)। Food and Agriculture Organization of the United Nations। পৃষ্ঠা 68–71। আইএসবিএন 92-5-104543-7। 
  6. ↑ ক খ গ ঘ ঙ Martin, R.A.। "Biology of the গবলিন হাঙর"। ReefQuest Centre for হাঙর Reসমুদ্রrch। সংগ্রহের তারিখ এপ্রিল ২৫, ২০১৩। 
  7. ↑ Shirai, S. (১৯৯৬)। "Phylogenetic interrelationships of neoselachians (Chondrichthyes: Euselachii)"। Stiassny, M.L.J.; Parenti, L.R.; Johnson, G.D.। Interrelationships of Fishes। Academic Press। পৃষ্ঠা 9–34। আইএসবিএন 0-08-053492-9। 
  8. ↑ Shimada, K. (২০০৫)। "Phylogeny of lamniform হাঙরs (Chondrichthyes: Elasmobranchii) and the contribution of dental characters to lamniform systematics"। Paleontological Reসমুদ্রrch। 9 (1): 55–72। ডিওআই:10.2517/prpsj.9.55। 
  9. ↑ Naylor, G.J.P.; Martin, A.P.; Mattison, E.; Brown, W.M. (১৯৯৭)। "The inter-relationships of lamniform হাঙরs: testing phylogenetic hypotheses with sequence data"। Kocher, T.D.; Stepien, C.A.। Molecular Systematics of Fishes। Academic Press। পৃষ্ঠা 199–218। আইএসবিএন 0-08-053691-3। 
  10. ↑ Naylor, G.J.; Caira, J.N.; Jensen, K.; Rosana, K.A.; Straube, N.; Lakner, C. (২০১২)। "Elasmobranch phylogeny: A mitochondrial estimate based on 595 প্রজাতি"। Carrier, J.C.; Musick, J.A.; Heithaus, M.R.। The Biology of হাঙরs and Their Relatives (second সংস্করণ)। CRC Press। পৃষ্ঠা 31–57। আইএসবিএন 1-4398-3924-7। 
  11. ↑ Sepkoski, J.; Antinarella, J.; McMahon, J. (২০০২)। "A compendium of fossil marine animal genera (Chondrichthyes entry)"। Bulletins of American Paleontology। 364: 560। 
  12. ↑ Nelson, J.S. (২০০৬)। Fishes of the World (fourth সংস্করণ)। John Wiley & Sons। পৃষ্ঠা 54। আইএসবিএন 0-471-75644-X। 
  13. ↑ Vialle, N.; Adnet, S.; Cappetta, H. (২০১১)। "A new হাঙর and ray fauna from the Middle Miocene of Mazan, Vaucluse (southern France) and its importance in interpreting the paleoenvironment of marine deposits in the southern Rhodanian Basin"। Swiss Journal of Palaeontology। 130 (2): 241–258। ডিওআই:10.1007/s13358-011-0025-4। 
  14. ↑ Pledge, N.S. (১৯৬৭)। "Fossil Elasmobranch teeth of South Australia and their stratigraphic distribution"। Transactions of the Royal Society of South Australia। 91: 135–160। 
  15. ↑ Purdy, R. (২০০৫)। "Is Striatolamia a junior synonym of Mitsukurina?"। Journal of Vertebrate Paleontology। 25 (3): 102A। ডিওআই:10.1080/02724634.2005.10009942। 
  16. ↑ Birx, H.J., সম্পাদক (২০০৯)। Encyclopedia of Time: Science, Philosophy, Theology, & Culture (Volume 1)। SAGE Publications। পৃষ্ঠা 547। আইএসবিএন 1-4129-4164-4। 
  17. ↑ ক খ Parsons, G.R.; Ingram, G.W.; Havard, R. (২০০২)। "First record of the গবলিন হাঙর Mitsukurina owstoni, Jordan (family Mitsukurinidae) in the Gulf of Mexico"। Southeastern Naturalist। 1 (2): 189–192। ডিওআই:10.1656/1528-7092(2002)001[0189:FROTGS]2.0.CO;2। 
  18. ↑ ক খ Last, P.R.; Stevens, J.D. (২০০৯)। হাঙরs and Rays of Australia (second সংস্করণ)। Harvard University Press। পৃষ্ঠা 156–157। আইএসবিএন 0-674-03411-2। 
  19. ↑ "Mitsukurina"। www.fishesofaustralia.net.au। সংগ্রহের তারিখ ২০১৬-০৪-০৫। 
  20. ↑ Rincon, G.; Vaske, T.; Gadig, O.B. (২০১২)। "Record of the গবলিন হাঙর Mitsukurina owstoni (Chondrichthyes: Lamniformes: Mitsukurinidae) from the south-western Atlantic"। Marine Biodiversity Records। 5: e44। ডিওআই:10.1017/S1755267211000923। 
  21. ↑ Kukuyev, E.I. (১৯৮২)। "Ichthyofauna of Corner Mountains and New England সমুদ্রmounts"। Parin, N.V.। Insufficiently Studied Fishes of the Open Ocean. Moscow: Institute of Oceanology। Institute of Oceanology, Academy of Sciences of the USSR। পৃষ্ঠা 92–109। 
  22. ↑ Prokofiev, A.M.; Kukuev, E.I. (২০০৯)। "New findings of rare fish প্রজাতি from families Mitsukurinidae (Chondrichthyes), Muraenidae, Lophiidae, Macrouridae, and Psychrolutidae (Teleostei) on rises of the Atlantic Ocean with the description of Gymnothorax walvisensis sp. nov"। Journal of Ichthyology। 49 (3): 215–227। ডিওআই:10.1134/S0032945209030023। 
  23. ↑ ক খ Martin, R.A.। "Deep সমুদ্র: গবলিন হাঙর"। ReefQuest Centre for হাঙর Reসমুদ্রrch। সংগ্রহের তারিখ এপ্রিল ২৫, ২০১৩। 
  24. ↑ ক খ গ Ebert, D.A. (২০০৩)। হাঙরs, Rays, and Chimaeras of California। University of California Press। পৃষ্ঠা 96–97। আইএসবিএন 0-520-22265-2। 
  25. ↑ ক খ "Scientists amazed by accidental Gulf catch of second-ever গবলিন হাঙর"। SFGate। ২ মে ২০১৪। সংগ্রহের তারিখ ৩ মে ২০১৪। 
  26. ↑ "Valaichchena strange fish"। lankadeepa.lk (Sinhala ভাষায়)। Sri Lanka। সংগ্রহের তারিখ ৫ আগস্ট ২০১৫। 
  27. ↑ Izawa, K. (২০১২)। "Echthrogaleus mitsukurinae sp. nov (Copepoda, Siphonostomatoida, Pandaridae) infesting the গবলিন হাঙর Mitsukurina owstoni Jordan, 1898 in Japanese waters"। Crustaceana। 85 (1): 81–87। ডিওআই:10.1163/156854012x623674। 
  28. ↑ Caira, J.N.; Runkle, L.S. (১৯৯৩)। "2 new tapeworms from the গবলিন হাঙর Mitsukurina owstoni off Australia"। Systematic Parasitology। 26 (2): 81–90। ডিওআই:10.1007/BF00009215। 
  29. ↑ Yano, K.; Miya, M.; Aizawa, M.; Noichi, T. (২০০৭)। "Some aspects of the biology of the গবলিন হাঙর, Mitsukurina owstoni, collected from the Tokyo Submarine Canyon and adjacent waters, Japan"। Ichthyological Reসমুদ্রrch। 54 (4): 388–398। ডিওআই:10.1007/s10228-007-0414-2। 
  30. ↑ Duffy, C.A.J. (১৯৯৭)। "Further records of the গবলিন হাঙর, Mitsukurina owstoni (Lamniformes: Mitsukurinidae), from New Zealand"। New Zealand Journal of Zoology। 24 (2): 167–171। ডিওআই:10.1080/03014223.1997.9518111। 
  31. ↑ "গবলিন হাঙর caught alive"। Tokyo Zoo Net। Tokyo Zoological Park Society। জানুয়ারি ২৫, ২০০৭। সংগ্রহের তারিখ এপ্রিল ২৬, ২০১৩। 
  32. ↑ Bean, B.A. (১৯০৫)। "Notes on an adult গবলিন হাঙর (Mitsukurina owstoni) of Japan"। Proceedings of the United States National Museum। 28 (1409): 815–818। ডিওআই:10.5479/si.00963801.28-1409.815। 

বহিঃ সংযোগ

উইকিমিডিয়া কমন্সে গবলিন হাঙর সংক্রান্ত মিডিয়া রয়েছে।

টেমপ্লেট:Lamniformes

'https://bn.wikipedia.org/w/index.php?title=গবলিন_হাঙর&oldid=2514494' থেকে আনীত