Keeled scales refer to reptile scales that, rather than being smooth, have a ridge down the center that may or may not extend to the tip of the scale, making them rough to the touch. According to Street's (1979) description of European lizards and snakes, in those that have keeled scales the keels are usually stronger in male specimens and are consistently arranged according to the species of reptiles, even though many others do not have them. With European lizards, the dorsal scales are usually well keeled, while those on the flanks are more weakly keeled and those on the belly smooth. Non-European lizards such as Sphaerodactylus macrolepis also display keeled scales.
Vipera berus, the common European adder or common European viper, is a venomous snake that is extremely widespread and can be found throughout most of Central Europe and Eastern Europe, and as far as East Asia.
Macrovipera lebetinus, known as the blunt-nosed viper, Lebetine viper, Levant viper, and by other common names, is a viper species found in North Africa, much of the Middle East, and as far east as Kashmir. Like all other vipers, it is venomous. Five subspecies are currently recognized, including the nominate race described here.
Atheris squamigera is a venomous viper species endemic to west and central Africa. No subspecies are currently recognized.
Atheris barbouri is a small and rare terrestrial species of viper endemic to the Uzungwe and Ukinga mountains of south-central Tanzania in Africa. No subspecies are recognized.
Vipera is a genus of vipers. It has a very wide range, being found from North Africa to just within the Arctic Circle and from Great Britain to Pacific Asia. The Latin name vīpera is possibly derived from the Latin words vivus and pario, meaning "alive" and "bear" or "bring forth"; likely a reference to the fact that most vipers bear live young. Currently, 21 species are recognized. Like all other vipers, the members of this genus are venomous.
Vipera ammodytes is a viper species found in southern Europe, mainly northern Italy, the Balkans, and parts of Asia Minor. Like all other vipers, it is venomous. It is reputed to be the most dangerous of the European vipers due to its large size, long fangs and high venom toxicity. The specific name, ammodytes, is derived from the Greek words ammos, meaning "sand", and dutes, meaning "burrower" or "diver", despite its preference for rocky habitats. Five subspecies are currently recognized, including the nominate subspecies described here.
Vipera aspis is a viper species found in southwestern Europe. Its common names include asp, asp viper, European asp, and aspic viper, among others. Like all other vipers, it is venomous. Bites from this species can be more severe than from the European adder, V. berus; not only can they be very painful, but approximately 4% of all untreated bites are fatal. The specific epithet, aspis, is a Greek word that means "viper." Five subspecies are currently recognized, including the nominate subspecies described here.
Montivipera albizona, the central Turkish mountain viper, is a viper species endemic to the mountainous regions of central Turkey. Like all other vipers, it is venomous. No subspecies are currently recognized.
Vipera transcaucasiana is a venomous viper species endemic to parts of Georgia and northern Turkish Anatolia.
Vipera aspis francisciredi is a venomous viper subspecies endemic to northern and central Italy and adjacent Croatia, Slovenia, and Switzerland.
Vipera aspis zinnikeri is a venomous viper subspecies endemic to the Pyrenees region of Spain and France.
Vipera darevskii, known as Darevsky's viper, is a small species of viper, a venomous snake in the subfamily Viperinae of the family Viperidae. The species is native to northwestern Armenia, northeastern Turkey, and possibly also adjacent southern Georgia. There are no subspecies that are recognized as being valid.
Vipera dinniki is a viper species native to the Caucasus Mountains region, part of Russia, Georgia, and Azerbaijan. Like all other vipers, it is venomous. No subspecies are currently recognized.
Vipera seoanei is a venomous viper species endemic to extreme southwestern France and the northern regions of Spain and Portugal. Two subspecies are currently recognized, including the nominate race described here.
Vipera ursinii is a species of venomous snake in the subfamily Viperinae of the family Viperidae. It is a very rare species, which is in danger of extinction. This species is commonly called the meadow viper. It is found in France, Italy, and Greece as well as much of eastern Europe. Several subspecies are recognized. Beyond the highly threatened European population, poorly known populations exist as far to the east as Kazakhstan and northwestern China.
Wagner's viper, known as the ocellate mountain viper, ocellated mountain viper, and Wagner's viper, is a species of venomous snake in the subfamily Viperinae of the family Viperidae. The species is native to eastern Turkey and northwestern Iran. There are no subspecies that are recognized as being valid.
The Hungarian meadow viper, also called the Danubian meadow viper is one of the eight subspecies of the Vipera ursinii. It is an extremely rare venomous viper that can mostly be found in Hungary. The Hungarian meadow viper is the most endangered species in the whole Pannonian Basin. It was scientifically recorded for the first time in 1893 by Lajos Méhelÿ, Hungarian zoologist. In 2004, its entire Hungarian population was estimated to be below 500 specimens.
