Vipera aspis

Vipera aspis is a venomous viper species found in southwestern Europe. Bites from this species can be more severe than from the European adder, V. berus; not only can they be very painful, but according to Stemmler (1971), about 4% of all untreated bites are fatal.^[3] The specific name, aspis, is a Greek word that means "viper."^[4] Five subspecies are currently recognized, including the nominate subspecies described here.^[5]

Description

Grows to an average length of 60-65 cm. Males reach a maximum of 85 cm, females rarely more than 75 cm. Males, however, are a little slimmer than females. The tail is very short: one-seventh to one-ninth of total body length in females, and one-sixth to one-eighth in males.^[1]

Midbody, there are 21-23 (rarely 19 or 25) rows of dorsal scales. These are strongly keeled, except for the outermost rows that vary and are sometimes smooth. There are 134-170 ventral scales. Subspecies V. a. aspis averages fewer than 150 ventrals, while V. a. atra averages more. The anal scale is single. Males have 32-49 subcaudals, females 30-43.^[1] The subcaudal scales are paired.^[3]

The dorsal markings vary strongly, but only rarely take the form of a clear zigzag, as in V. berus.^[1]

Common names

Asp, asp viper,^[1] European asp,^[2] aspic viper,^[3] European viper,^[6] Jura viper.^[7]

Geographic range

In August-October 2006, a number of specimens were discovered in a wooded area near the town of Portugaal in the Netherlands (south of Rotterdam). Although they were doing quite well, the species is not native in this country. It is likely that one or more escaped or were set loose in the area.^[10]^[11]

Conservation status

This species is classified as Least Concern (LC) according to the IUCN Red List of Threatened Species (v3.1, 2001). So listed due to its wide distribution, tolerance of a broad range of habitats, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category.

However, subspecies V. a. aspis is categorized as Critically Endangered in Switzerland, V. a. atra is categorized as Vulnerable, and V. a. francisciredi is categorized as Endangered (Monney and Meyer, 2005).^[12]^[13]

In general, the species is also listed as protected (Appendix III) under the Berne Convention.^[14]

Habitat

This species has a few clearly defined and relatively specific habitat requirements. It needs warm areas that are exposed to the sun, structured vegetation and comparatively dry soils. In Italy and France, it is often found in areas with low mountains or hills, notably in limestone regions, but sometimes occurs in lower plains. It has a preference for vegetated areas or environments with at least some cover.^[1] Here it can be found on sunny slopes, on scrublands, in glades, in mountain meadows, forest clearings, at the borders of woods, in rubbish dumps and in stone quarries.^[3] In Italy, it occurs in mesic chestnut/oak woodlands and often near streams.^[1] Although it is not really associated with high altitudes, in the Pyrenees it has been found at well over 2,100 m above sea level.^[15]

Venom

The toxicity of the venom varies. Stemmler (1971) states that the population in Passwang district, Switzerland have the strongest venom.^[3] Compared to venoms from other species, it is relatively toxic. Brown (1973) gives LD₅₀ values of 1.0 mg/kg IV and 1.0-2.0 mg/kg SC.^[16] Tu et al. (1969) reports 4.7 mg/kg IM. Venom yield is relatively low. Boquet (1964) reported a daily extraction figure of 9-10 mg.^[1]

Envenomation symptoms include rapidly spreading acute pain, followed by edema and discoloration. Severe haemorrhagic necrosis may occur within a few hours. Vision may be severely impaired, most likely due to degradation of blood and blood vessels in the eyes. The venom has both coagulant and anticoagulant effects. Anticoagulant activity is apparently stronger than that of Daboia russelii. The venom may also affect glomerular structure, which can lead to death due to renal failure.^[1]

According to Cheymol et al. (1973), the venom does not affect neuromuscular contractions in in vitro preparations. Lack of this neurotoxic affect would indicate that fatal cases involving the cardiovascular system are the result of direct muscle injury or reduced oxygen exchange. On the other hand, Gonzalez (1991) reported that in two cases the victims developed neurotoxic symptoms, including difficulty in breathing and swallowing, as well as paralysis of the bitten limbs.^[1]

Subspecies

Subspecies^[5]	Taxon author^[5]	Common name^[6]	Geographic range^[1]
V. a. aspis	(Linnaeus, 1758)	European asp	Found in most of France, except those areas bordering the English Channel. On the Atlantic coast, it is found in �le de R� and Ol�ron, but not south of the Gironde estuary. Mostly absent east of the Moselle River and from much of the Mediterranean region, but does occur near Montpellier and in Alpes-Maritimes. A disjunct subpopulation exists in the Pyrenees, notably in Spain southwest of Bilbao. In Germany it occurs in the southern Black Forest along the Swiss border, but is rare in this area. It is common northwestern Italy and western Switzerland.
V. a. atra	Meisner, 1820	Black asp	Parts of Switzerland.
V. a. francisciredi	Laurenti, 1768	Central Italian asp	Central Italy.
V. a. hugyi	Schinz, 1833	Southern Italian asp	The south of Italy.
V. a. zinnikeri	Kramer, 1958	Gascony asp	Gascony, Andorra and nearby Spain.

Vipera aspis

Contents

Description

Common names

Geographic range

Conservation status

Habitat

Venom

Subspecies

See also

References

Further reading

External links