Vipera (; commonly known as the palaearctic vipers and Eurasian vipers) 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. Description The members of this genus tend to be stout and small in size, the largest of them, V. ammodytes, can reach a maximum length of 95 cm and the smallest, V. monticola, reaches a maximum length of 40 cm. The heads of the members of this genus are clearly separated from the body, they are triangular in shape and in most species are covered in small scales, although in some species, notably V. berus, have small plates on the top of their heads. Most species have large supraocular scales that tend to extend beyond the posterior margin of the eye. Some species also have some sort of horn on the head, either right behind the nasal scale, or behind the supraocular scales. The color scheme and camouflage of the members of this genus vary widely, from a grayish ground color with dark brown transverse bands to browner colors with grey transverse bands edged with black in the case of V. ammodytes.Geographic range They can be found all around the Old World, hence the common name of the genus, "Old World vipers". they can be found most notably in Europe, from Portugal to Turkey. They can also be found on some islands in the Mediterranean Sea (Sicily, Elba and Montecristo), and the United Kingdom. They can also be found in the Maghreb region of Africa with species living in Morocco (V. monticola) and northern parts of Algeria and Tunisia in the case of V. latastei. Many species can also be found in the Caucasus mountains, parts of Iraq, Jordan, Israel and Syria. Only one species (V. berus) discovered so far lives in East Asia, most notably North Korea, northern China and northern Mongolia. Habitat Most species prefer cooler environments. Those found at lower latitudes tend to prefer higher altitudes and dryer, rocky habitats, while the species that occur at more northern