Black desert cobra
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Black desert cobra ( Walterinnesia aegyptia ) |
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| Walterinnesia aegyptia | ||||||||||||
| Lataste , 1887 |
The black desert cobra ( Walterinnesia aegyptia ; English Black Desert Cobra ; fr. Cobra noire du désert ) is a poisonous snake from the genus of the desert cobras ( Walterinnesia ).
description
The snake usually reaches a length of 90 to 120 cm. The basic color of the clearly shiny scales varies from a solid dark brown to black, with the wide belly shields being noticeably lighter. Young animals of W. aegyptia are all black in color like the adults. Drawn or banded young animals are to be assigned to the species Walterinnesia morgani .
The broad, strong, slightly triangular head hardly separates from the body. The eyes are black with their pupils black .
Scaling
The scales on the front half of the body are almost smooth, the scales on the back of the body are slightly to moderately keeled. Around the middle there are 21 to 23 rows of back scales, in the neck there are 27 rows of scales. The anal shield ( scutum anale ) is divided. The under- tail shields ( Scutum subcaudale ) have very irregular division ratios, as some scales are not divided and others are doubly divided. The number of ventralia (abdominal scales) is between 186 and 198. The number of undivided subcaudalia (lower tail shields) is between 3 and 13. The pre-eye shield ( praeoculare ) is particularly long and connects to the rear nasal shield ( scutum nasale ). Like all cobras of the genus Walterinnesia , the black desert cobra lacks the characteristic neck shield and rein shield ( scutum loreale ).
distribution and habitat
The overall distribution of the genus Walterinnesia extends over the following countries or states: Egypt, Iraq, Iran, Israel, Jordan, Kuwait, Saudi Arabia, Syria and Turkey. According to current knowledge, however, only the countries: Egypt, Israel, Jordan and Syria are inhabited by the species Walterinnesia aegyptia . The species has not yet been found in Lebanon, but it could be possible.
It prefers sandy and stony terrain with often very sparse bushes in order to be able to hide easily. You can also find them in damp oases , overgrown gardens and old ruins . Desert areas are avoided. During the day she hides under rocks and stones, in crevices and in small animal structures.
Way of life
This snake is almost exclusively active at dusk and at night, whereas during the day it hides in places protected from the sun. Since it mostly lives underground, the black desert cobra rarely comes into contact with humans. If you startle her, she curls up and hides her head under the loops of her body. However, if it feels threatened, a loud hissing and usually several bites follow in defense. Due to the poor eyesight, she relies almost exclusively on her sense of smell when hunting.
The main food source of the desert cobra are lizards , especially the genus Uromastyx , smaller snakes , amphibians and various toads , long-tailed mice and birds .
Little is known about reproduction, fresh hatched young animals were found in September. The species lays up to 20 eggs in the terrarium. The incubation under terrarium conditions is about 74-77 days at 25-28 ° C. The young animals shed their skin for the first time after about 14 days.
toxicology
The poisonous secretion of the black desert cobra mainly contains postsynaptic neurotoxins , which inhibit neurotransmission by blocking acetylcholine receptors ( nicotine receptors ) . There are various toxins from the class of three-finger toxins , such as three-finger toxin W-IV. This leads to symptoms of paralysis and even paralysis . Death can result from peripheral respiratory paralysis . Other possible symptoms and complications include local pain, headache, blood pressure disorders, cardiac arrest or allergic shock. There are few clinical reports of bite accidents in humans, but the toxin mixture is believed to be highly effective against the human organism as well. The LD 50 value for a mouse is 0.4 mg per kg of body weight. Treatment with a species-specific or polyvalent snake serum is the most important therapeutic option in the case of neurotoxic symptoms. Due to their hidden way of life, bite accidents are very rare.
Individual evidence
- ↑ Uniprot: Three-finger toxin W-IV (accessed June 30, 2018)
- ↑ a b c University of Adelaide, Clinical Toxinology Resources: Walterinnesia aegyptia (accessed June 30, 2018)
literature
- Ulrich Gruber: The snakes of Europe and around the Mediterranean, Franckh-Kosmos-Verlag, ISBN 3-440-05753-4
Al-Jammaz, I., Al-Sadoon, MK, Fahim, A. & Attia, MA (1994): The Effects of Walterinnesia aegyptia Venom on the Serum and Tissue Metabolites and on Some Enzyme Activities in Albino Rats. III-Effects on Lipid Metabolism and Two Dehydrogenases. - J. King Saud Univ., Sci., 6 (2): 207-215.
- (1995): Effects of the Venoms of Walterinnesia aegyptia and Echis coloratus on Solute Levels in the Plasma of Albino Rats. - J. King Saud Univ., Sci., 7 (1): 63-69.
- (2001): Physiological Effect of LD50 of Walterinnesia aegyptia Crude Venom on rat Metabolism Over Various Periods of Time. - Pakistan J. Biol. Sci., 4 (11): 1429-1431.
Boulenger, GA (1920): A List of Snakes from Mesopotamia. - Jour. Bombay Nat. Hist. Soc., Bombay, 27: 347-350.
Büttiker, W. & Krupp, F. (1988): Fauna of Saudi Arabia, 9: 477 pp.
Castoe, TA, Smith, EN, Brown, RM & Parkinson, CL (2007): Higher-level c Phylogeny of Asian and American coralsnakes, their placement within the Elapidae (Squamata), and the systematic affinities of the enigmatic Asian coralsnake Hemibungarus calligaster (Wiegmann, 1834). - Zool. J. Linnean Soc., 151: 809-831.
David, P. & Vogel, G. (2010): Venomous snakes of Europe, North, Central and West Asia.– Frankfurt / M. (Edition Chimaira): 160 pp.
Disi, AM (1990): Venomous Snakes in Jordan. - in: Gopalakrishnakone, P. & Chou, LM (1990): Snakes of Medical Importance (Asia-Pacific Region), 676 pp.
-, Modry, D., Nečas, P. & Lifai, L. (2001): Amphibians and Reptiles of the Hashemite Kingdom of Jordan. - Frankfurt / M. (Edition Chimaira), 408 pp.
Göçmen, B., Franzen, M., Yildiz, MZ, Akman, B. & Yalçinkaya, D. (2009): New locality records of eremial snake species in southeastern Turkey (Ophidia: Colubridae, Elapidae, Typhlopidae, Leptotyphlopidae). - SALAMANDRA, Rheinbach, 45 (2): 110-114.
Internet: http://www.pondturtle.com/bsnaked.html Kelly, CMR, Barker, NP, Villet, MH & Broadley, DG (2009): Phylogeny, Biogeography and classification of the snake superfamily Elapoidea: a rapid radiation in the Late Eocene. - Cladistics, 25: 38-63.
Kochva, E. (1990): Venomous Snakes of Israel. - in: Gopalakrishnakone, P. & Chou, LM (1990): Snakes of Medical Importance (Asia-Pacific Region), 676 pp.
Lifshitz, M., Maimon, N. & Livnat, S. (2003): Walterinnesia aegyptia envenomation in a 22-year-old female: a case report. - Toxicon , 41 (4): 535-537.
Mahaba, HM (2000): Snakebite: Epidemiology, Prevention, Clinical Presentation and Management. - Ann. Saudi Medicine, 20 (1): 66-68.
Marx, H. (1953): The elapid genus of snakes Walterinnesia . Fieldiana, Chicago, 34 (16): 189-196.
Mohamed, AH & Zaky, O. (1954): Biochemical and Physiological Studies of the Purified Toxin of Walterinnesia aegyptia "The Egyptian Black Snake". - J. Exp. Biol., 33: 502-507.
Nilson, G. & Rastegar-Pouyani, N. (2007): Walterinnesia aegyptia Lataste, 1887 (Ophidia: Elapidae) and the status of Naja morgani Mocquard, 1905. - Russian J. Herp., Moscow, 14 (1): 7 -14.
Scortecci, G. (1939): Gli Ofidi Velenosi dell'Africa Italiana. - Milano, 292 pp.
Trutnau, L. (1998): Venomous snakes. Snakes in the Terrarium (4th edition) - Stuttgart (Ulmer Verlag), 367 pp. - (1981): Schlangen 2 (3rd edition). - Stuttgart (Ulmer Verlag), 271 pp.
Uğurtaş, IH, Papenfuss, TJ & Orlov, NL (2001): New record of Walterinnesia aegyptia Lataste, 1887 (Ophidia: Elapidae: Bungarinae) in Turkey. - Russian J. Herp., Moscow, 8 (3): 239-245.
van Issem, P. (2011): Keeping and breeding of the black desert cobra Walterinnesia aegyptia LATASTE, 1887 - SAURIA, 33 (4): 57-70.
Wall, F. (1908): Notes on a collection of snakes from Persia. - Jour. Bombay Nat. Hist. Soc., Bombay, 18: 795-805.
Wüster, W., Crookes, S., Ineich, I., Mané, Y., Pook, CE, Trape, J.-F. & Broadley, DG (2007): The phylogeny of cobras inferred from mitochondrial DNA sequences: Evolution of venom spitting and the phylogeography of the African spitting cobras (Serpentes: Elapidae: Naja nigricollis complex). - Mol. Phylogues. Evol., San Diego, 45: 437-453.
Yayon, E., Sikular, E. & Keynam, A. (1988): Desert black snake ( Walterinnesia aegyptia ) bites - a presentation of four cases. - Harefuah, 115: 269-270.
Web links
- Black Desert Cobra on Reptiles Database
- Walterinnesia aegyptia in The Reptile Database
- Walterinnesia aegyptia inthe IUCN 2013 Red List of Threatened Species . Posted by: Amr, ZSS, Al Johany, AMH, Egan, DM, Baha El Din, S., Ugurtas, IH, Werner, YL, Disi, AM, Tok, V. & Sevinç, M., 2012 . January 2014.