Levan Otter
| Levan Otter | ||||||||||||
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Levant Otter ( Macroektivena lebetina ) |
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| Macrohabena lebetina | ||||||||||||
| ( Linnaeus , 1758) |
The Levant Otter ( Macroektivena lebetina ) is a species of snake from the family of the vipers (Viperidae). It is the largest viper in Europe , but only occurs here in Dagestan and thus on the far eastern edge of the continent. The entire distribution area extends from Cyprus via Turkey , Iraq and Iran to Afghanistan and Pakistan , there are also isolated occurrences in North Africa . Five subspecies are recognized. The Levant Otter, like all vipers, is poisonous; however, the bite is fatal to humans only in exceptional cases.
description
The Levant Otter is on average 80 to 100 centimeters long, but regionally it can also reach lengths of 160 centimeters (proven for Turkmenistan ) with a maximum weight of about 2.7 kilograms. The females are usually slightly larger than the males.
The snake's physique is strong. The basic color is mostly light gray, but can also be gray-green, beige, yellow or red-brown regionally. The body scales have a distinct keel. The individual subspecies can be distinguished from one another mainly on the basis of the number of rows of backs (dorsals) and ventral scales and the ratio of tail length to total length. All subspecies are variable in color, whereby regionally different color morphs may be more common.
The drawing on the back consists of two rows of staggered transverse bands, which are darker than the body and sometimes connected to form a wavy band. With some color variants this drawing is only very indistinct and especially with the subspecies M. l. obtusa hardly recognizable. The Levant Otter also has a series of darker spots on the sides of its body known as bar spots. In addition to these drawings, there are irregular spots with very small yellow to ocher spots of color. The ventral side is light gray to gray-brown or pink in color and shows darker mottling. The tip of the tail can be pink to orange or yellowish. Young animals are usually gray to earth-colored and have no spots.
The head, clearly separated from the body, has a triangular rounded shape. It is covered with many small and keeled scales, with the super-eye shields (supraocularia) being divided into two or three individual scales. The pupil of the very large eyes is slit vertically. Between the edge of the eye and the shields of the upper lip there are two, less often three, rows of under eye shields (subocularia). The top of the head is not drawn, but a dark band runs from the eyes to the corner of the mouth (temple band).
distribution
The Levantotter lives in several subspecies, especially in the eastern Mediterranean and in southwest Asia.
The nominate form M. l. lebetina is found in Cyprus and on the coasts of Turkey . M. l. Obtusa is distributed from Israel via Eastern Turkey and Transcaucasia to Afghanistan and West Pakistan . M. l. turanica and M. l. cernovi are found from Kazakhstan to northern Iran , northern Afghanistan, northwestern Pakistan and western Kashmir . Endemic is separated from the other subspecies in North Africa in Tunisia and Algeria occurring M. l. transmediterranea . Further, not recognized subspecies are M. l. euphratica from Turkey and M. l. bearing from southern Afghanistan and northern Pakistan.
| subspecies | First describer | distribution |
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| M. l. cernovi | ( Chikin & Ščerbak , 1992) | Northeast Iran, South Turkmenistan, North Afghanistan and Pakistan (Kashmir). |
| M. l. lebetina | ( Linnaeus , 1758) | Cyprus, Turkey |
| M. l. obtusa | ( Dwigubsky , 1832) | Turkey, Syria , Lebanon , Iraq, North Jordan , Caucasus (including Armenia ), Azerbaijan , Dagestan , Iran, southern Afghanistan, Pakistan, North India (Kashmir) |
| M. l. transmediterranea | ( Nilson & Andrén , 1988) | Algeria, Tunisia |
| M. l. turanica | ( Cernov , 1940) | East Turkmenistan, Uzbekistan , Tajikistan , Southwest Kazakhstan, North Afghanistan, and West Pakistan |
habitat
The Levant Otter prefers warm and dry areas with sparse vegetation , such as steppes , mountain slopes or scree areas. They are very often found on slopes that lead to bodies of water. Vines and warm vegetable gardens are also visited quite often by the snake, otherwise it is rarely found in human dwellings and then only in quiet, little-used buildings.
In the mountains it can be found regularly up to 1500 meters, the highest finds were at around 2000 to 2500 meters in the Kopet Dagh and the Pamir .
Way of life
The Levant otter lives primarily on the ground, but it is also able to climb into bushes and smaller trees. In the mornings, she spends time on areas exposed to direct sunlight to warm her body. Your activity times are very dependent on the outside temperatures. In spring and autumn it is mainly active during the day, in midsummer mainly in the cooler twilight period and at night. This is also reflected regionally, in the north of its area it is accordingly more diurnal, in the south more nocturnal. In the case of populations in the mountains, seasonal migrations have been found; in summer the animals stay in the area of streams and in winter in the barren rocky regions. In winter it hibernates for two to six months . Hibernation takes place in crevices or abandoned mammalian structures in individual numbers from one to about 20 snakes. The sexually mature animals shed their skin three times a year as a rule: the first time after the hibernation, a second time in midsummer and finally in autumn. Young snakes, on the other hand, molt more often.
nutrition
The Levant otter is not very specialized in its food choices. The diet consists mainly of small mammals such as rats , small rabbits and mice . It also prey on birds, frogs, lizards and smaller snakes as well as large insects and arachnids such as roller spiders (Solifugae). The composition of the prey varies greatly from region to region, but mostly mammals and birds make up the majority. For the Nuratau Mountains it is described that the snakes here have specialized in ambushing songbirds at the bird bath. The prey is killed in one bite, held in place and, as with all snakes, devoured completely.
Investigations in a large serpentarium in Tashkent revealed that the snakes consumed the largest amounts of food between May and June and reduced their food intake to a minimum in July. From August onwards, the amount increased again until the end of the year and then decreased again in the first few months of the year. A snake around 80 centimeters long can take up to five chicken chicks per meal and thus a mass of around 200 to 250 grams. Digestion takes three to five days in summer and five to seven days in winter.
Enemies
Although the Levant Otter has a very potent venom and is also relatively large, the juvenile snakes in particular are threatened by a number of predators. These include, above all, other snakes such as the sand rattle otter ( Echis carinatus ) and the Central Asian cobra ( Naja oxiana ), the desert monitor ( Varanus griseus ) and birds of prey such as the black kite ( Milvus migrans ) or the buzzard ( Buteo rufinus ). The remains of the Levant otter were also found in stomach analyzes of red foxes ( Vulpes vulpes ). The snake usually reacts to disturbances by fleeing. If she does not have the opportunity to escape, she snaps very quickly and violently.
Reproduction and development
The sexual maturity occurs at the Levant Otter to 44 to 46 months and a total length of about 70 centimeters. The mating takes place, depending on the region, from April to May, in some regions also in September to October. The females mate several times during this time, each copulation can last from about 15 minutes to several hours. The fertilized embryos can take a break, the so-called diapause , in their development .
The females of the Levant Otter lay their eggs ( oviparia ) from mid-May to late June or even late July to August, depending on the subspecies and region. As a rule, a clutch consists of 14 to 20 eggs, the range extends from 6 to over 40 eggs. After about one to two months, the young snakes hatch with a total length of about 15 to 20 centimeters. For the Levant otters in Azerbaijan, in addition to the influence of the abiotic environmental conditions, an influence of the available amount of food on fertility could be determined: With a decreasing small mammal density, the potential of the population to produce offspring also decreased significantly.
Systematics
For a long time, the Levant otter was classified in the genus of real otters ( Vipera ), along with most other European vipers. In 1992, the genus was revised, in which the Levant otter was classified into the genus Macroektivena along with three other species on the basis of biochemical characteristics . The Cycladic viper ( Macrophia schweizeri ), which had been regarded as a subspecies of the Levant otter, was also recognized as a separate species and described as a sister species of the Levant otter. She lives as an islander in the Milos Archipelago and probably also on the island of Kythnos in the Aegean Sea. The two North African species Sahara otter and Atlas otter completed the genus.
By Lenk et al. In 2001, however, this compilation was questioned. On a molecular biological basis, the sister group relationship of Levant otter and Cycladic viper can be maintained, the African species, on the other hand, are closely related to the chain viper ( Daboia russelii ) and the Palestinian viper ( Daboia palaestinae ), which is why the African macro vipera and the Palestine viper were assigned to the genus Daboia suggested. Accordingly, only the Levant otter and the Cycladic viper belong to the genus Macroocket .
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This view is confirmed by Garrigues et al. 2004, when the vipers form a European section from different Vipera species as well as an oriental section from the named genera Daboia and Macrophia as well as the Montivipera species. As with Lenk et al. In 2001 the genus of grand vipers is paraphyletic in the current compilation, the chain viper ( Daboia russeli ) forms a taxon with the Palestine viper and the atlas otter (the Sahara otter and the Cycladic viper were not part of the study). Mallow et al. In 2003, the Palestine otters were classified accordingly in the genus, the Atlas otters were named by Wüster et al. based on the results of Lenk et al. put to Daboia .
Poison
Poisonous effect
As with all snakebites, the effectiveness of a Levant otter's bite depends on many factors: size of the snake, last time the snake consumed food, time of year and daytime temperature at the time of the bite, the constitution and bite region of the victim.
A bite requires immediate medical attention and an antiserum . Under no circumstances should the bite wound be tied, sucked out, cut open or burned out. If the poisoning is local, life-threatening symptoms are rare. However, severe bite courses have also been reported. The venom induces severe swelling of the bite area, which spreads. It comes to the edema to necrosis of the tissue. Coagulation disorders and kidney dysfunction can occur. More general symptoms include nausea with vomiting, an increased heart rate, cramps, and motor disorders such as dizziness and numbness of the extremities.
Deaths caused by Levant otters are very rare and only occur in the absence of treatment; extensive necrosis with the resulting amputation of the affected limbs is also rare .
composition
The poison of the Levant Otter is a very thick and amber colored liquid. It is a very effective hemotoxin and has a cytotoxic effect. It destroys the vessel walls and leads to internal bleeding, at the same time it leads to pathological coagulation and thus thrombosis .
The individual components of the poison are not yet fully explored and how many other snake venoms contain it next frequently found in snake venoms substances also species-specific proteins such as the 2001 discovered proteins Live Cetin and Lebetin that in 2004 discovered Lebectin and the 2005 discovered Live statin . Most of the ingredients are widely used in medicine as blood clots and liquefiers, as well as in cancer medicine .
Threat and protection
The human influence on Levant Otter populations is high. A large number of them die in traffic or are killed if the animals are found too close to settlements. Their habitat is often grazed and overgrazed by flocks of sheep and thus destroyed.
According to the Bern Convention , the Levant otter is included in Appendix II and is accordingly strictly protected. Even according to the Washington Convention on the Protection of Species (CITES) and the Federal Nature Conservation Act (BNatSchG), the Levant Otter is strictly protected and is listed in Appendix I, and trade in animals is accordingly prohibited.
In Asia, however, catching snake venom is allowed, so they are kept in large serpentine arenas. Often thousands of snakes are caught. In Tashkent, for example, there were 5,530 otters in 1972. In particular, animals taken from nature above one meter in length refuse to feed in captivity and die relatively quickly.
swell
literature
- Nikolay Ščerbak, Wolfgang Böhme: Macrophia lebetina (Linnaeus, 1758) - Levant otter. In: Ulrich Joger, Nikolai Stümpel: Snakes (Serpentes) 3. Viperidae. Aula, Wiebelsheim 2005, ISBN 3-89104-617-0 (Handbook of the Reptiles and Amphibians of Europe; Volume 3 / 2B), pages 25–42.
- Ulrich Gruber: The snakes of Europe. Franckh, Stuttgart 1989, ISBN 3-440-05753-4 , pages 205-207.
- David Mallow, David Ludwig, Göran Nilson: True Vipers. Natural History and Toxinology of Old World Vipers. Krieger, Malabar 2003, ISBN 0-89464-877-2 , pages 193-204.
Sources cited
Most of the information in this article has been taken from the sources given under literature; the following sources are also cited:
- ↑ a b Macrohabena lebetina (TSN 634977) in the Integrated Taxonomic Information System (ITIS).
- ↑ Ludwig D. Mallow, G. Nilson: True Vipers: Natural History and Toxinology of Old World Vipers. Krieger, Malabar 2003, ISBN 0-89464-877-2 .
- ↑ H.-W. Herrmann, U. Joger, G. Nilson: Phylogeny and systematics of viperine snakes. III: resurrection of the genus Macroektivena (Reuss, 1927) as suggested by biochemical evidence. In: Amphibia-Reptilia. 13, 1992, pp. 375-392.
- ↑ P. Lenk, S. Kalayabina, M. Wink, U. Joger: Evolutionary relationships among the true vipers (Reptilia: Viperidae) inferred from mitochondrial DNA sequences (PDF; 139 kB). In: Molecular Phylogenetics and Evolution 19, 2001, pp. 94-104 (English).
- ↑ Thomas Garrigues, Catherine Dauga, Elisabeth Ferquel, Valérie Choumet, Anna-Bella Failloux: Molecular phylogeny of Vipera Laurenti, 1768 and the related genera Macrophia (Reuss, 1927) and Daboia (Gray, 1842), with comments about neurotoxic Vipera aspis aspis populations. In: Molecular Phylogenetics and Evolution 35 (1), 2005, pp. 35-47.
- ↑ David Mallow, David Ludwig, Göran Nilson: True Vipers. Natural History and Toxinology of Old World Vipers. Krieger Publishing Company Malabar, Florida, 2003; Pages 141-159, ISBN 0-89464-877-2 .
- ↑ Wolfgang Wüster, Lindsay Peppin, Catharine E. Pook, Daniel E. Walker: A nesting of vipers: Phylogeny and historical biogeography of the Viperidae (Squamata: Serpentes). In: Molecular Phylogenetics and Evolution 49, 2008, pp. 445-459 (English).
- ↑ Saray et al. a .: Lebecetin, a C-lectin protein from the venom of Macrophia lebetina that inhibits platelet aggregation and adhesion of cancerous cells. In: Haemostasis. 31, 3-6, 2001, pp. 173-176, PMID 11910182
- ↑ N. Marrakchi et al. a .: Lebetin peptides: potent platelet aggregation inhibitors. In: Haemostasis. 31, 3-6, 2001, pages 207-210, PMID 11910186
- ↑ Saray et al. a .: Lebectin, a novel C-type lectin from Macrophia lebetina venom, inhibits integrin-mediated adhesion, migration and invasion of human tumor cells. In: Laboratory Investigation . 84, 5, 2004, pages 573-581, PMID 15048137
- ↑ KZ Olfa u. a .: Lebestatin, a disintegrin from Macroocket venom, inhibits integrin-mediated cell adhesion, migration and angiogenesis. In: Laboratory Investigation. 85, 12, 2005, pages 1507-1516, PMID 16200076
- ↑ Convention on the Conservation of European Wildlife and animals and their habitats, Appendix II to Council of Europe (English)
- ↑ Listing according to CITES and BNatSchG
