Eirenis

Head -banded dwarf snake ( Eirenis modestus )

The dwarf snakes ( Eirenis ) constitute a genus of snakes of the family of snakes, more precisely, the subfamily of land and tree snakes. In comparison to other closely related snakes of the genera Dolichophis and Hierophis they are much smaller and produce less dander.

Features

The dwarf snakes are small snake, whose body 's length is usually less than 75 centimeters. They have round pupils, relatively small eyes and broad head shields. Nasal is not divided, a Subokulare does not exist. Eirenis have ( caudal Scutum ) on the waist of only 15 or 17 dorsal scale rows and 100 tail scales. Dwarf snakes do not have fangs, are so aglyph.

Similarities with Hierophis and Dolichophis exist in the morphology of Hemipenises as well as the appearance of the young animals. This anger, however, snakes have a Präsubokular.

Inside systematics

Within the genus Eirenis four subgenera are distinguished: Eirenis, Pseudocyclophis, Eoseirenis and Pediophis. A total of 19 species are counted among the dwarf snakes. The type species is Eirenis modestus.

Subgenus Eirenis

This subgenus includes the dwarf relatively original snakes with less Verzwergungsmerkmalen. The body sizes of adult animals are between 55 and 65 centimeters. You have 6 Temporal, 17, rarely 19 dorsal scale rows and less than 200 ventral scales. Also, there are individuals in which the nasals are half divided.

  • Eirenis aurolineatus ( Venzmer, 1919)
  • Eirenis modestus ( Martin, 1838)

Subgenus Eoseirenis

This subgenus includes only one species, Eirenis decemlineatus ( Dumeril, Bibron & Dumeril, 1854), which has the lowest Verzwergungsmerkmalen among all dwarf snakes. Adult animals are up to 75 centimeters long and have large eyes in comparison. You have 6 Temporal, 17 dorsal scale rows and less than 200 ventral scales.

Subgenus Pediophis

This subgenus includes the dwarf most snakes with varying degrees of Verzwergungsmerkmalen. The body sizes of adult animals are between 30 and 60 centimeters. You have 4 or 6 Temporal, 17 or 19 dorsal scale rows and less than 200 ventral scales.

  • Eirenis africana ( Boulenger, 1914)
  • Eirenis barani schmidtler, 1988
  • Eirenis collaris ( Ménétries, 1832)
  • Eirenis coronella ( SCHLEGEL, 1837)
  • Eirenis coronelloides (JAN, 1862)
  • Eirenis eiselti schmidtler & schmidtler, 1978
  • Eirenis hakkariensis schmidtler & EISELT, 1991
  • Eirenis levantinus schmidtler, 1993
  • Eirenis lineomaculatus SCHMIDT, 1939
  • Eirenis mcmahoni ( WALL, 1911)
  • Eirenis medus ( Chernov, 1940)
  • Eirenis rechingeri EISELT, 1971
  • Eirenis rothii JAN 1863
  • Eirenis thospitis schmidtler & LANZA, 1990

Subgenus Pseudocyclophis

This subgenus includes only one species, Eirenis persicus ( ANDERSON, 1872), which has very strong Verzwergungsmerkmale. Adult animals are up to 45 centimeters long. You have 4 Temporal, 15 dorsal scale rows, but usually more than 200 ventral scales.

Outer systematics

The genus Hierophis includes the genus of dwarf snakes ( Eirenis ) with one, therefore is thus paraphyletic. The following diagram shows the family relationship on the basis of studies of Nagy et al. 2004, which is why Andrew's whip snake, which was not part of the genetic testing is missing.:

Dolichophis

H. gemonensis

H. viridiflavus

H. spinalis

Eirenis

Dissemination

The distribution of snakes of the genus Eirenis stretches from Turkey in the west through Georgia and Dagestan in the north to the east to Turkmenistan, Pakistan and Afghanistan, and includes the Arabian Peninsula. Only Eirenis africana lives across the Red Sea between Sudan and Djibouti.

Eirenis coronella is the only dwarf viper that lives in the Arabian desert.

Way of life

While the closely related anger snakes are big and fast and lizards and rodents hunt, most dwarf snakes live hidden and are crepuscular. Their diet consists of arthropods. This change in lifestyle has potentially result in the dwarfing.

Squamata Giorgio Jan Balkan whip snake Digital Object Identifier
300296
de