Halysotter ( Gloydius halys )
|( Pallas , 1776)|
The Halysotter ( Gloydius halys ), also Halys otter , is a species of the genus Halysottern ( Gloydius ) within the Asian pit otter (Crotalinae). It is distributed over large parts of Asia and is also the only pit viper to be found in parts of Europe.
The Halysotter is a medium-sized viper and reaches an average length of about 60 to 70 cm, with individual individuals also up to 80 cm long. The basic color is variable from light gray to light brown through reddish brown to orange with a back markings made of dark brown cross bars and cross spots. The sides of the body have a series of small dark spots just above the abdominal scales. The belly is a single color, light gray and rarely speckled with black. A dark band of temples stretches over the eyes to the neck, and on the top of the head there may be further drawings in the form of triangles. As a pit viper, the snake has a distinct pit organ between the nostril and the eye.
The head is flat and angular and clearly set off from the body. The relatively small eyes have vertical pupils . On the top of the head there are a total of 9 clearly recognizable and unresolved head shields. Below the eyes there are two to three rows of under eye shields ( supraocularia ). The body scales are keeled. There are 23 rows of scales around the middle of the body. The under- tail shields ( Subcaudalia ) are divided as in all species of the genus.
distribution and habitat
The distribution area stretches over Russia to Siberia , east of the Urals to the south to Iran and touches Europe on the northern edge of the Caspian Sea and in the Transcaucasus . To the east, the area extends to Mongolia and China as well as the Ryukyu Islands of Japan .
The habitat of the snake is very different due to the large distribution area. The snake can be found in different habitats from the lowlands to the high mountains at altitudes of 2,500 to 3,500 m. Above all, it prefers steppes, mountain slopes, scree areas, mountain meadows and river banks with denser vegetation.
Way of life
The Halysotter is predominantly crepuscular and is a pure ground snake. In the morning it can be seen sunbathing, especially in northern or very high areas. As a rule, it is well camouflaged on the ground; if threatened, it makes a rattling noise by rubbing a horn nail on the underside of the tail on the ground. If the disturbance persists, it will jump forward and bite hard. Depending on the area, it hibernates, which can last between 4 and 6 months. The snake feeds mainly on small mammals , birds and bird eggs. The young snakes hunt lizards and grasshoppers.
The mating season is from April to May, following the winter dormancy. The snake is viviparous ( ovoviviparous ) and gives birth to 3 to 12 young animals in early autumn. The females are able to store sperm for years and give birth to young animals without re-copulation.
Until the beginning of the 1990s, depending on the author, a number of American, Asian and European viper species were assigned to the genus Agkistrodon , combined in a taxon "Agkistrodontini" or referred to as the "Agkistrodon complex". The great difficulties in the systematic classification of the species were essentially due to the lack of differentiation between original ( symplesiomorphic ) and derived ( apomorphic ) morphological features in this evolutionarily relatively original snake group.
Molecular genetic studies of the mitochondrial DNA have since proven the common ancestry ( monophyly ) of the American representatives of the genus. Furthermore, it was found that these are much more closely related to the rattlesnakes (genera Crotalus and Sistrurus ) than to the Eurasian species that were previously assigned to Agkistrodon . These Eurasian species have since been included under the previously proposed genus Gloydius ( Halysotters ). The taxon "Agkistrodontini" was rejected as obviously paraphyletic .
Within the genus Gloydius , the two Asiatic species Gloydius blomhoffi and Gloydius intermedius are the closest relatives of the Halysotter. These were sometimes considered to be subspecies of the Halysotter, but are now recognized as separate species due to molecular biological data and characteristics of the scaling.
Most of the information in this article has been taken from the sources given under literature; the following sources are also cited:
- Christopher L. Parkinson, Scott M. Moody, Jon E. Ahlquist: Phylogenetic relationships of the 'Agkistrodon complex' based on mitochondrial DNA sequence data. Symp zool. Soc. London 70, 1997; Pp. 63-78
- Jonathan A. Campbell, William W. Lamar: The Venomous Reptiles of the Western Hemisphere. Comstock; Ithaca, London. 2004. ISBN 0-8014-4141-2
- José C. Brito, Hubert Saint Girons: Gloydius halys (Pallas, 1776) - Halysotter. In: Ulrich Joger, Nicolai Stümpel: Schlangen (Serpentes) III Viperidae. in the series Manual of Reptiles and Amphibians in Europe Volume 3 / IIB. Aula-Verlag, Wiebelsheim 2005, ISBN 3-89104-617-0 , pp. 7-22.
- Ulrich Gruber: The snakes in Europe and around the Mediterranean. Franckh'sche Verlagsbuchhandlung, Stuttgart 1989, ISBN 3-440-05753-4 , pp. 227-229.