Vipera walser

Vipera walser
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Genus:	Vipera
Species:	V. walser
Binomial name
	Vipera walser; Ghielmi, Menegon, Marsden, Laddaga & Ursenbacher 2016

Vipera walser, the Walser viper or Piedmont viper is a viper endemic to the western Italian Alps. While long considered as an isolated population of Vipera berus, molecular analyses have shown it to be a distinct species related to the Vipera ursinii-complex.^[1]^[2]

Morphology

Morphologically, Vipera walser closely resembles the far more widespread Vipera berus. It differs in having a higher number of cephalic scales and more frequently shows fragmentation of the cephalic large shields. Additionally, most individuals possess 1.5 to 2 rows of subocular scales at both sides of the head, while Vipera berus usually only has a single row. Colouration is highly variable, with some specimens possessing a typical dorsal zigzag pattern, and others with a reduced pattern of horizontal bars.^[1] Additionally, melanistic individuals exist.

Geographic range

Vipera walser is limited to a small area north of the Italian town of Biella.^[1] The range is divided in a northern population of ±45 km² and a southern population of ±225 km².^[3]

Ecology

Vipera walser occurs in open habitats at an altitude of 1300-2300 m in valleys with high precipitation. It is mostly found on gentle south-oriented slopes with low forest cover.^[3]

Threats and conservation

Due to its recent description, Vipera walser has not yet been evaluated by IUCN, although the original species description argues that the limited extent of occurrence (<1000 km²) warrants a classification as 'endangered'.^[1] Fragmented habitat, decline in agropastoral landuse, culling and collection pose short-term threats, while in the long term climate change may alter the distribution. Additionally, low genetic variability may make the species even more prone to disturbances.^[1]

References

^ ^a ^b ^c ^d ^e Ghielmi, Samuele; Menegon, Michele; Marsden, Stuart J.; Laddaga, Lorenzo; Ursenbacher, Sylvain (2016). "A new vertebrate for Europe: the discovery of a range-restricted relict viper in the western Italian Alps". Journal of Zoological Systematics and Evolutionary Research. 54 (3): 161–173. doi:10.1111/jzs.12138. S2CID 88740081.
^ Speybroeck, Jeroen (2016). Field guide to the amphibians & reptiles of Britain and Europe. Wouter Beukema, Bobby Bok, Jan Van der Voort, Ilian Velikov. London. ISBN 978-1-4729-3533-5. OCLC 889164386.{{cite book}}: CS1 maint: location missing publisher (link)
^ ^a ^b Ficetola, Gentile Francesco; Fanelli, Mauro; Garizio, Lorenzo; Falaschi, Mattia; Tenan, Simone; Ghielmi, Samuele; Laddaga, Lorenzo; Menegon, Michele; Delfino, Massimo (2020). "Estimating abundance and habitat suitability in a micro-endemic snake: the Walser viper" (PDF). Acta Herpetologica. 15 (2): 73–85.

[:0-1] Ghielmi, Samuele; Menegon, Michele; Marsden, Stuart J.; Laddaga, Lorenzo; Ursenbacher, Sylvain (2016). "A new vertebrate for Europe: the discovery of a range-restricted relict viper in the western Italian Alps". Journal of Zoological Systematics and Evolutionary Research. 54 (3): 161–173. doi:10.1111/jzs.12138. S2CID 88740081.

[2] Speybroeck, Jeroen (2016). Field guide to the amphibians & reptiles of Britain and Europe. Wouter Beukema, Bobby Bok, Jan Van der Voort, Ilian Velikov. London. ISBN 978-1-4729-3533-5. OCLC 889164386.{{cite book}}: CS1 maint: location missing publisher (link)

[:1-3] Ficetola, Gentile Francesco; Fanelli, Mauro; Garizio, Lorenzo; Falaschi, Mattia; Tenan, Simone; Ghielmi, Samuele; Laddaga, Lorenzo; Menegon, Michele; Delfino, Massimo (2020). "Estimating abundance and habitat suitability in a micro-endemic snake: the Walser viper" (PDF). Acta Herpetologica. 15 (2): 73–85.

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