Sahara otter
| Sahara otter | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Daboia deserti | ||||||||||||
| ( Anderson , 1892) |
The Sahara otter ( Daboia deserti , Syn . : Macroektivena deserti ) is a North African viper belonging to the genus of the Oriental vipers .
description
The Sahara otter is up to 160 cm long and is one of the larger vipers. It has a broad and triangular head, clearly separated from the body, with a rounded and short snout and comparatively small eyes with vertically slit pupils .
Scaling
The shields on the top of the head are divided into small, keeled scales . The upper eye shields are also broken up into smaller scales. The eyes are surrounded by a ring of 12 to 18 circumorbtalia. The eyes are separated from the 11 to 12 upper lip shields (supralabials) by two or three rows of lower eye shields. The large nostrils lie in a single, large nasal shield made up of nasals and nasorostrals.
With the exception of the last row in contact with the ventral scales, the body and head scales are strongly keeled. On the back there are usually 27 rows of scales around the middle of the body. On the abdominal side there are 164 to 170 abdominal shields (ventralia) and after an undivided anal shield 44 to 51 paired under tail shields (subcaudalia) are present. The tail is comparatively long.
coloring
The basic color of the snake is gray to yellowish with 23 to 26 offset black spots that form a back pattern. The pattern dissolves with age, so that older animals only have very indistinct markings. Individuals without drawing are also known.
distribution and habitat
The range of the snake is limited to the higher desert areas in Libya and Tunisia and the foot of the Atlas Mountains in Algeria . The semi-arid habitat is characterized by drought and very sparse vegetation as well as a stony or sandy subsoil.
Way of life
The Sahara otter is nocturnal and spends the hotter times of the day under stones, in caves and under vegetation. The food spectrum of the adult snakes consists mainly of small mammals and birds, while the young ones prey on lizards. The snakes capable of climbing also prey on young birds and eggs from nests.
Unlike most vipers, the Sahara otter lays eggs and females lay up to 20 eggs.
Systematics
→ Main article: Oriental vipers # systematics
The Saharan otter was first described by Anderson in 1892 as a subspecies of the Levantotter ( Macrophia lebetina ) and later regarded as a subspecies of the Atlas otter ( Daboia mauritanica ). For a long time it was classified in the genus of the real vipers ( Vipera ). In 1992, the genus Vipera was revised , in which the atlas viper was placed in the genus of large vipers ( Macrophia ) together with three other species on the basis of biochemical characteristics , while the chain viper was the only species of the genus Daboia .
By Lenk et al. However, in 2001 this view was challenged. On a molecular biological basis, the assignment of the African Macroocket and the Palestine Aviper to the genus Daboia was proposed. This view is confirmed by Garrigues et al. 2004: As with Lenk et al. In 2001 the genus of large vipers is paraphyletic in the current compilation, the chain viper ( Daboia russeli ) forms a taxon with the Palestine viper and the former African large viper species . Mallow et al. In 2003, the Palestine aviper was assigned to the genus Daboia , while the atlas and Sahara otters were classified by Wüster et al. as well as in the IUCN Red List based on the results of Lenk et al. put to Daboia .
Danger
The Sahara otter is listed in the IUCN Red List as a type of warning list ("near threatened") due to its small distribution area and the decreasing population.
supporting documents
- ↑ Herrmann, H.-W., U. Joger & G. Nilson (1992): Phylogeny and systematics of viperine snakes. III: resurrection of the genus Macroektivena (Reuss, 1927) as suggested by biochemical evidence. Amphibia-Reptilia, 13: 375-392
- ↑ Lenk, P., S. Kalayabina, M. Wink & U. Joger (2001) Evolutionary relationships among the true vipers (Reptilia: Viperidae) inferred from mitochondrial DNA sequences. Molecular Phylogenetics and Evolution 19: 94-104. ( Full text PDF )
- ↑ Thomas Garrigues, Catherine Dauga, Elisabeth Ferquel, Valérie Choumet and Anna-Bella Failloux: Molecular phylogeny of Vipera Laurenti, 1768 and the related genera Macroypena (Reuss, 1927) and Daboia (Gray, 1842), with comments about neurotoxic Vipera aspis aspis populations. 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). Molecular Phylogenetics and Evolution 49 (2008); Pp. 445-459.
- ↑ Daboia deserti in the IUCN Red List of Threatened Species 2009.2. Posted by: Miras, JAM, Joger, U., Pleguezuelos, J. & Slimani, T., 2006. Retrieved January 4, 2010.
literature
- David Mallow, David Ludwig, Göran Nilson: True Vipers. Natural History and Toxicology of Old World Vipers, Krieger Publishing Company, Malabar (Florida) 2003; Pages 194-195. ISBN 0-89464-877-2