Viperidae

Desert horned viper

Or vipers vipers ( Viperidae ), are a common in the Americas, Africa and Eurasia family usually viviparer ( viviparous ) poisonous snakes with 39 genera and, depending on the design, 308 species. All species of this taxon are poisonous.

While they are completely absent in Australia, Oceania, and Madagascar, they are represented in Europe with 13 species: The viper has the largest distribution area, at the height of the Alps, it is replaced in the south of the asp. In the north of the Iberian Peninsula lived the Nordiberische viper, still exist in Spain and Portugal, the greater Lataste. From Austria and Switzerland to Southeast Europe to the Black Sea survived the European viper. The meadow viper is Europe's smallest and rarest Viper. In the Caucasus, there is the steppe viper, the Caucasus and the Western Caucasus Otter Otter. The forest-steppe viper is found in Ukraine. While the previously mentioned to the genuine viper (Vipera ) are there from the kind of mountain vipers ( Montivipera ) the small Asian Mountain Otter and from the kind of large-scale vipers ( Macrovipera ) the Milosviper as well, with up to 220 cm, the largest Viper Europe, the Levante Otter. The only European pit viper is the Halysotter.

Description

Depending on the type they reach a length of 30 cm to more than three meters. The often stocky, massive acting snakes are characterized by a short tail and a triangular, usually clearly separated from the neck head. With the exception of toads vipers, all vipers on vertically slotted elliptical pupils, a reference to the mostly crepuscular and nocturnal lifestyle. Vipers are rarely conspicuous, often colored in rather dark earth or olive tones.

In some species ( ovoviviparous species) mature the eggs in the mother's body and the young hatch in the egg-laying, but there are also a number of egg-laying ( oviparous ) species.

Vipers have a highly developed venom apparatus with movable tubular ( solenoglyphs ) fangs. When the mouth is closed, the fangs are " collapsed " in a Bindegewebsfalte in the roof of the mouth and are erected perpendicular to the upper jaw when the mouth torn open by the rotation of two bones ( maxillary and Präfrontalknochen ). This is a very deep penetration of the teeth enables the prey, and it can be an effective injection of the snake venom.

Snake venom

Most viper venoms are particularly hemotoxic so destroy especially cells of the blood and the surrounding tissue by various proteases. Hämotoxine lead to extensive tissue damage, internal bleeding and swelling and necrosis and are very painful. Among the most effective ingredients of the poison also include proteins that suppress blood clotting and cause together with the tissue-destructive proportions internal bleeding. Bleeding occur in this case under the skin, nasal and oral cavity, and especially in the gut and brain of the prey. Besides these there are in some species also neurotoxic components that act on the nervous system of the victim and cause paralysis. These are used primarily in some rattlesnakes, such as the South American rain rattlesnake (Crotalus durissus ) or some puff adders before ( Bitis ).

System

The Vipers are one of seven families within the superfamily of vipers and viper -like ( Colubroidae ). The systematics of snakes is still the subject of current investigations. After pyrone et al. arises within the Colubroidae following system:

Vipers ( Viperidae )

Snakes ( Colubridae )

Poison snakes ( Elapidae )

Lamprophiidae

Water phantom snakes ( Homalopsidae )

Pareatidae

Hump ​​snakes ( Xenodermatidae )

Within the Vipers, a distinction about 308 species that are assigned into three subfamilies around 39 genera. The main groups within the vipers are on the one hand, the rights vipers ( Viperinae ) and on the other pit vipers ( Crotalinae ), which eg rattlesnakes (Crotalus ) belong. In contrast to this the genuine vipers lack the lies before the eyes of the pit organ, a heat sensory organ. Another subfamily, Azemiopinae, consists of only one kind of ( feae Azemiops ) Fea 's viper.

Mainly due to data of mitochondrial DNA as well as the composition of the poison the Fea 's viper is now set as the basal taxon in the vipers ( Viperidae ). However, other molecular biological investigations, to position them as a sister group of pit vipers ( Crotalinae ) within the vipers and based on some morphological characteristics such as the pupil and the body form a mapping in the relationship of toads vipers ( Causinae ) was suspected. Finally, the systematic assignment is not clear according to this day.

The following recent genera are assigned to the Vipers:

The subfamily contains a single Azemiopinae Art Azemiops feae is a very original Viper, which still has many features that resemble snakes or poisonous snakes, such as the slender body and large head shields.

• Fea - vipers ( Azemiops )

The snakes of the subfamily pit vipers ( Crotalinae ) stand next to the pit organ is also characterized by an additional muscle to the venom glands. The Reptile Database leads 213 species (as of May 2012) in the following genera:

• Triangle head vipers ( Agkistrodon )
• Jumping Terciopelos ( Atropoides )
• Palm Terciopelos ( Bothriechis )
• Forest Terciopelos ( Bothriopsis )
• Bothrocophias
• Bothropoides
• American Terciopelos ( Bothrops )
• Malaysian Mokassinottern ( Calloselasma )
• Mountain pit viper ( Cerrophidion )
• Rattlesnakes (Crotalus )
• Chinese nose vipers ( Deinagkistrodon )
• Garthius
• Gloydius
• Ceylon nose vipers ( Hypnale )
• Bushmaster ( Lachesis )
• Mixcoatlus
• Mixocoatlus
• Mexican Horn Terciopelos ( Ophryacus )
• Ovophis
• Hook nose Terciopelos ( Porthidium )
• Protobothrops
• Rhinocerophis
• Dwarf rattlesnakes ( Sistrurus )
• Bamboo viper ( Trimeresurus )
• Temple otters ( Tropidolaemus )

The snakes in the subfamily of the Real vipers ( Viperinae ) lack the pit organ. The Reptile Database leads 94 species (May 2012) in the following genera:

• Bush vipers ( Atheris )
• Puff adders ( Bitis )
• Toads vipers ( Causus )
• African horn viper ( cerastes )
• Oriental vipers ( Daboia )
• Sand race wabble ( Echis )
• MacMahon Vipers ( Eristicophis )
• Great vipers Macrovipera
• East African mountain otters ( Montatheris )
• Mountain otters Montivipera
• Swamp vipers ( Proatheris )
• Mirage horn vipers ( Pseudocerastes )
• True vipers (Vipera )