Vipers

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Vipers
Desert horned viper

Desert horned viper

Systematics
Superordinate : Scale lizards (Lepidosauria)
Order : Scale reptiles (Squamata)
without rank: Toxicofera
Subordination : Snakes (serpentes)
Superfamily : Adder-like and viper-like (Colubroidea)
Family : Vipers
Scientific name
Viperidae
Oppel , 1811

Vipers or otters (Viperidae) are a common family of venomous snakes in America, Africa and Eurasia with 39 genera and, depending on the interpretation, almost 340 species . All species of this taxon are poisonous.

While they are completely absent in Australia, Oceania and Madagascar, they are represented by around 15 species in Europe: the adder has the largest range, at the level of the Alps it is replaced in the south by the aspis viper. In the north of the Iberian Peninsula lives Vipera Seoanei , still exist in Spain and Portugal, the greater Vipera Latastei . The European horned viper lives from Austria and Switzerland to south-eastern Europe to the Black Sea . The meadow otter is Europe's smallest and rarest viper. In the Caucasus there are the steppe viper , the Caucasian viper and the western Caucasian viper . The forest steppe otter occurs in Ukraine. While the formerly mentioned belong to the real otters ( Vipera ), there are from the genus of mountain otters ( Montivipera ) the Asia Minor mountain otters and from the genus of large vipers ( Macroypena ) the Milo viper and, with up to 220 cm, the largest viper in Europe, the Levan Otter . The only European pit viper is the halysotter .

description

Depending on the species, they can reach a length of 30 cm to over three meters. The snakes, which are often squat, seemingly massive, are characterized by a short tail and a triangular head, usually clearly separated from the neck. With the exception of the toad vipers , all vipers have vertically slit elliptical pupils , an indication of the mostly crepuscular and nocturnal lifestyle. Vipers are seldom conspicuous, often colored in rather dark earth or olive tones.

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

Vipers have a highly developed venomous apparatus with movable tubular ( solenoglyphs ) fangs. When the mouth is closed, the poison teeth lie “folded” in a fold of connective tissue in the roof of the palate and when the mouth is torn open, two bones (maxillary and prefrontal bones) turn perpendicular to the upper jaw. This enables the teeth to penetrate very deeply into the prey, and the snake venom can be injected effectively .

Snake venom

Most viper poisons are primarily hemotoxic , i.e. primarily destroy cells of the blood and the tissues surrounding them with various proteases . Hemotoxins lead to extensive tissue destruction, internal bleeding and swelling as well as necrosis and are very painful. The most effective components of the poison also include proteins that suppress blood clotting and thus together with the tissue-destroying components cause internal bleeding. Bleeding occurs under the skin, in the nasal and oral cavities and above all in the intestines and brain of the prey. In addition to these, there are also neurotoxic components in some species that act on the victim's nervous system and cause paralysis. These occur mainly in some rattlesnakes such as the South American shower rattlesnake ( Crotalus durissus ) or some puff adders ( Bitis ).

Systematics

The vipers are one of seven families within the superfamily of the adder- and viper-like (Colubroidae). The system of snakes is still the subject of current research. According to Pyron et al. the following system arises within the Colubroidae:

 Adder-like and viper-like 



Vipers (Viperidae)


   

Adders (Colubridae)


   


Poison Snakes (Elapidae)


   

Lamprophiidae



   

Water snakes (Homalopsidae)





   

Pareidae



   

Mute snakes (Xenodermatidae)



The fea viper ( Azemiops feae ) is neither a pit otter nor a real otter.

Within the vipers a distinction is made between almost 340 species, which are assigned to around 39 genera in three subfamilies. The main groups within the vipers are firstly the Real vipers (Viperinae) and on the other pit vipers (Crotalinae), z to which. B. the rattlesnakes ( Crotalus ) belong. In contrast to these, the real vipers lack the pit organ in front of the eyes , a warmth sense organ. Another subfamily, the Azemiopinae, consists of only one genus ( Azemiops ) with two species, the Fea viper ( Azemiops feae ) and Azemiops kharini .

Azemiops is now set as a basal taxon in the vipers (Viperidae), mainly due to data from the mitochondrial DNA and the composition of the poison . Other molecular biological studies, however, classify the vipers as a sister group of the pit vipers (Crotalinae), and on the basis of some morphological features such as the pupil and body shape, an assignment to the relationship of the toad vipers (Causinae) was assumed. Finally, the systematic allocation has not yet been clarified.

The following recent genera are assigned to the vipers:

The subfamily Azemiopinae includes a genus with two species. In Azemiops feae and Azemiops kharini is very original vipers which still have many features of snakes or poisonous snakes remember, such as the slender body and big head shields.

The snakes of the subfamily pit vipers (Crotalinae) are not only characterized by the pit organ but also by an additional muscle on the venom glands. The Reptile Database lists 237 species (as of September 2016) in the following genera:

The sidewinder rattlesnake ( Crotalus cerastes ) belongs to the pit vipers.

The snakes in the subfamily of the real vipers (Viperinae) lack the pit organ. The Reptile Database lists 100 species (as of September 2016) in the following genera:

The adder ( Vipera berus ), which is widespread in Europe, is one of the real vipers.

literature

  • Jonathan A. Campbell, William W. Lamar: The Venomous Reptiles of the Western Hemisphere. Cornell University Press, 2004, ISBN 0-8014-4141-2 .
  • Andreas Gumprecht, Frank Tillack: A proposal for a replacement name of the snake genus Ermia Zhang. 1993. In: Russian Journal of Herpetology. 11, 2004, pp. 73-76.
  • P. Guo, A. Malhotra, PP Li, CE Pook, S. Creer: New evidence on the phylogenetic position of the poorly known Asian pitocket 'Protobothrops kaulbacki' (Serpentes: Viperidae: Crotalinae) with a redescription of the species and a revision of the genus 'Protobothrops'. In: Herpetological Journal. 17, 2007, pp. 237-246.
  • KF Liem, H. Marx, GB Rabb: The viperid snake Azemiops: Its comparative cephalic anatomy and phylogenic position in relation to Viperinae and Crotalinae. In: Fieldiana: Zoology. 59 (2), 1971, pp. 67-126.
  • David Mallow, David Ludwig, Göran Nilson: True Vipers. Natural History and Toxicology of Old World Vipers. Krieger Publishing Company Malabar, Florida 2003, ISBN 0-89464-877-2 .
  • Ulrich Gruber: The snakes in Europe and around the Mediterranean . Franckh'sche Verlagsbuchhandlung, Stuttgart 1989, ISBN 3-440-05753-4 .
  • Ulrich Joger, Nikolai Stümpel (ed.): Handbook of the reptiles and amphibians of Europe. Volume 3 / IIB: Snakes (Serpentes) III Viperidae. Aula-Verlag, Wiebelsheim 2005, ISBN 3-89104-617-0 , pp. 151-185.

Web links

Commons : Viperidae  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Mario Schweiger: The venomous snakes of Europe . In: Reptilia . tape 76 , 2009, p. 14-25 .
  2. ↑ R. Alexander Pyron, Frank T. Burbrink, Guarino R. Colli, Adrian Nieto Montes de Oca, Laurie J. Vitt, Caitlin A. Kuczynski, John J. Wiens: The phylogeny of advanced snakes (Colubroidea), with discovery of a new subfamily and comparison of support methods for likelihood trees . In: Molecular Phylogenetics and Evolution . 2010, p. 329–342 , doi : 10.1016 / j.ympev.2010.11.006 .
  3. ^ Viperidae in The Reptile Database
  4. ↑ a b Nikolai L. Orlov, Sergei A. Ryabov, Tao Thien Nguyen: On the taxonomy and the distribution of snakes of the genus Azemiops Boulenger, 1888: Description of a new Species. In: Russian Journal of Herpetology. Vol. 20, No. 2, 2013, pp. 110–128.
  5. ↑ The Reptile Database: Higher Taxa in Extant Reptiles - Ophidia (Serpentes) - Snakes.
  6. ^ Azemiopinae in The Reptile Database
  7. ^ Crotalinae in The Reptile Database
  8. ^ Viperinae in The Reptile Database