Otenjeon Shark -Wikipedia
Source: Free encyclopedia “Wikipedia”
| Green turtle shark |
|---|
 |
| Conservation status evaluation [first] |
| VULNERABLE (IUCN Red List Ver.3.1 (2001))  |
| Classification |
| scientific name |
| Nebrius ferruginous ( Lesson , 1831) |
| synonym |
|
Ginglymostoma muelleri Günther, 1870 |
| English name |
| Tawny nurse shark |
distributed |
Green turtle shark (Same for the Great Tenjiku, Nebrius ferruginous ) Is a type of shark belonging to the glutinous shark family. The only raw species of the genus of the giant shark. Inhabits 70m or more along the Indian Pacific coast. The cylindrical body and the flat head are similar to whipped sharks, rice sharks, etc., but can be distinguished by sharp dorsal fins and sickle -shaped pectoral fins. Up to 3.2m.
In the daytime, they are resting in caves. At night, actively search for prey hidden in holes, suck and eat. The bait is mainly octopus, but also eats other small animals. Unlweding board fetal, the only egg food food. It is quite large when birth, and the number of children is small.
It has a powerful jaw and sharp teeth than a shark. In addition to being caught commercially, it is also treated as a game fish. IUCN is a urgent species.
At first, French musicians René-Primevère Lesson Based on a 1.4m specimen from New Guinea Scyllium ferrugineum Is described. The record in 1831 Tour du Monde Voyage, on the Corvette the shell Is published. Meanwhile, 1837, German musicians Eduard Rüppell Is conducting detailed research based on the specimens from the Red Sea, Nebrius concolor Is described. In 1984 Leonard Comrade Both names are separate until the synonym is Ginglymostoma and Neberry ) It was held as). Compagno has a difference in teeth that distinguish these two types N. color I revealed that it was a young individual [2] 。
Genus Neberry Is ancient Greek nebrad or nebriends It is derived from (yellow) and is due to the color of the skin. Nickname ferrugineus Is a “rust color” in Latin [3] 。 Based on the form comparison, Neberry The genus and the genus ( Ginglymostoma ) Is composed of a single structure group, and this group Pseudoginglymostoma brevicaudatum ・ Whale shark ( Rhincodon typus ) ・ Truffy shark ( Stegostoma fasciatum It is considered that it may be positioned in a clay containing) [4] 。
Distributed in the Indian Pacific Ocean. In the Indian Ocean, Kwazur Natal includes Red Sea, Persian Bay, India, Madagascar Mauritius Chagos Islands and Seishel Maldives. In the West Pacific, from southern Japan to the coast of China, the Philippines, Southeast Asia, Indonesia, and Australia. In the Central Pacific Ocean, it has been confirmed in the New Caledonia, Samoa Palau, Marshall Islands, and Tahiti. [2] 。 A fossiled teeth are excavated from the Pirabas layer in northern Brazil, dating back to the early Changin Health (23-16MA). This indicates that the distribution had extended to the tropical Atlantic before the formation of Panama. [5] 。
It is coastal, and inhabits the sand, seaweed grounds, coral reefs and rocky reefs on continental shelves. Normally, the depth is 5-30m, but it can be seen from the crushed wave zone to the depth of 70m of the coral reef, where the body is soaked. The uneven body is mainly in the shallow waters of lagoon [2] 。
Up to 3.2m [6] 。 A sturdy cylindrical body and a wide range of flat heads. The eyes are small on the side, the upper part is uplifted, and there is a small fountain hole behind. The pre -nose valve stretches out elongated and becomes a chip. The mouth is small, and the lower lip is divided into Miba. The upper jaw dentition is 29-33 and the lower jaw is 26-28. It is lined up in a tile, and is pushed into a narrow space except for the 2-4 columns on the outside. The teeth are fan -shaped, the base is wide, and there are 3 pairs of small sharpening. The teeth are high and thick as they grow. The fourth and fifth gills are close to other gills [2] [3] 。
The dorsal fins and pyros are square, and the first dorsal fin is larger than the second. The pectoral fin is thin, sharp and a sickle, and is different from other rice sharks. The first dorsal fin is directly above the gaps, and the second dorsal fin is attached to the top of the anal fin. The caudal fin reaches 1/4 of the overall length of the adult, has a low upper leaf and has almost no lower leaves. The teeth are rhizo, and 4-5 uplifting runs radially. The back is yellow, red, gray, etc., and the abdomen is gray -white. The body color can be changed slowly according to the environment. The lower eyelids are white in the young body [2] 。
On Japan, Okinawa and Taiwan coasts, there are individuals lacking the second dorsal fin. This may be the result of high salt concentration, temperature, or human activity, but the details are unknown. In 1986, a 2.9m adult male lacking the second dorsal fin was captured in Nachi Katsuura -cho. This individual is albino and is the largest shark albino that has been discovered so far. [7] [8] 。
It is considered to be more swimming because it is more streamlined than other sharks. The characteristics of the body, head, fins, and teeth are lemon sharks ( Negaprion acutidens ) It is equivalent to the active shark distributed in the same place. Captured individuals can be daylight depending on the time of food, and are always active in Madagascar, but basically they are nocturnal. During the day, more than 20 flocks gather under cave and rock shelves, and you can see the piles of resting and resting. Each individual has his own rest and returns there every day [2] 。
Other hot sharks are fluffy sharks ( Galeocerdo cuvier ) Although it is a prey for lemon sharks, there are few natural enemies of this species, large -sized giant whales ( Carcharhlnus leucas ) And Hirashimokku Swarse ( Spread Mokarran ) It is attacked by [3] 。 Parasitic to the spiral intestine Pedibothrium Five species of insects are known [9] 。
Feeding [ edit ]
It is a rare shark that dedicated octopus. [ten] 。 Other bait is coral, sea urchin, crustacean (crab lobster), squid, small fish (Nizadai, horse mackerel, igo), and rarely sea snake. While swimming slowly on the seabed, put your head into a hole to search for prey. When you find the prey, you open the muscular pharynx to generate negative pressure and inhale the prey. [2] 。
History of life [ edit ]
Madagascar will be crossed in June-August [2] 。 Adult females have one functional ovary and two uterus. It is a placental fetal life. It is the only egg -like eyes, and the fetus is used up with a large amount of eggs in the belly when the fetus is used up, and is used as a replacement of egg yolk. Unlike the rash shark, the eggs ingested by the fetus are large and have shells. Silowani ( Carcharias taurus ) The fetal cane is not observed [2] 。 There is a report of an egg birth, because the captured individual misunderstood the unequaled egg (up to 52). Egg sheaths are onion -shaped and have translucent, pale brown shells. [8] 。
The total length at birth varies depending on the region, but is 40-80cm. Females release up to four fertilized eggs to one uterus, but it is estimated that 1-2 animals are born because the newborns are quite large. One female had two fetuses in one uterus, and one was smaller than the other. From this, it is expected that the competition will eliminate either fetus. Sexual mature at 2.5m for males and females 2.3-2.9m [first] [2] 。
Relationship with people [ edit ]
It is quieter than other sharks, and usually can be touched by hand without any incident. However, if you provoke it, you may bite, and powerful jaws and small sharp teeth are dangerous. It is a specialty that is preferred in ecotourism such as the Thai Solomon Islands. It is bred in the aquarium, but gets used to people well and eats food from hands. [2] 。
It is not used in Australia, but is commercially caught in other distribution areas such as Pakistan, India, Thailand, and Philippines. [first] 。 The meat is raw, dried, and salted, fins are finefined, liver is liver oil, thick and durable skin is made into shark skin, and others are processed into fishmeal. In Queensland, it is treated as a game fish, and when it is applied to the needle, it resists stubbornly and twists the body to remove the needle. When it is withdrawn, it may spray water or groan, but it is unknown whether it is a defense action. [2] 。
IUCN is an urgent species, but it is difficult to recover from overfishing due to high catch pressure and low fertility and dispersion. In addition, it is influenced by the destruction of the habitat, poison, and fisheries using explosives. India and Thailand have reported regional decline and extinction. It is a mild concern because it is not subject to catch in Australia [first] 。
- ^ a b c d Imen, R. (2003). ” Nebrius ferruginous ” . IUCN Red List of Threatened Species. Version 2007 . International Union for Conservation of Nature June 7, 2009 Browsing 。
- ^ a b c d It is f g h i j k l Comrade, L.J.V. (2002). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date (Volume 2) . Rome: Food and Agriculture Organization. pp. 195–199. ISBN 9251045437
- ^ a b c Bester, C. Biological Profiles: Tawny Nurse Shark . Florida Museum of Natural History Ichthyology Department. Retrieved on June 7, 2009.
- ^ Goto, T. (2001). “Comparative Anatomy, Phylogeny and Cladistic Classification of the Order Orectolobiformes (Chondrichthyes, Elasmobranchii)”. Memoirs of the Graduate School of Fisheries Science, Hokkaido University 48 (1): 1–101.
- ^ dos Reis, M.A.F. (2005). “Chondrichthyan Fauna from the Pirabas Formation, Miocene of Northern Brazil, with Comments on Paleobiogeography”. Yearbook of the Institute of Geosciences 28 : 31–58.
- ^ Froese, Rainer and Pauly, Daniel, eds. (2009). ” Nebrius ferruginous ” in FishBase. June 2009 version.
- ^ Taniuchi, T. and YANAGISAWA, F. (1987). “Albinism and lack of second dorsal fin in an adult tawny nurse shark, Nebrius concolor , from Japan” . Japanese Journal of Ichthyology 34 (3): 393–395 .
- ^ a b Teshima, K., Kamei, Y., Toda, M. and Uchida, S. (December 1995). “Reproductive Mode of the Tawny Nurse Shark Taken from the Yaeyama Islands, Okinawa, Japan with Comments on Individuals Lacking the Second Dorsal Fin”. Bulletin of the Seikai National Fisheries Research Institute seventy three : 1–12.
- ^ Caira, J.N., Tracy, R. and Euzet, L. (2004). “Five new species of Pedibothrium (Tetraphyllidea: Onchobothriidae) from the Tawny nurse shark, Nebrius ferruginous , in the Pacific Ocean”. The Journal of Parasitology 90 (2): 286–300.
- ^ Smale, M.J. (Aug. 29, 1996). “Cephalopods as Prey. IV. Fishes” in “The Role of Cephalopods in the World’s Oceans”. Philosophical Transactions: Biological Sciences 351 (1343): 1067–1081.
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