Natrix maura is a natricine

Natricinae

Natricinae is a subfamily of the colubrid family of snakes which contains 28 genera. Members of this subfamily include many very common snake species, such as the European Grass Snakes, and the North American Water Snakes.- Genera :...

 water snake of the genus Natrix

Natrix

Natrix is a genus of colubrid snakes. There are three or four species in the genus. They are collectively called grass snakes and water snakes...

. Its common name is viperine water snake or viperine snake. Despite its common names, it is not a member of the Subfamily Viperinae

Viperinae

The Viperinae, or viperines, are a subfamily of venomous vipers found in Europe, Asia and Africa. They are distinguished by their lack of the heat-sensing pit organs that characterize their sister group, the Crotalinae. Currently, 12 genera and 66 species are recognized...

. This nonvenomous, semiaquatic, fish-eating snake was given its common names due to behavioural and aesthetic similarities

Batesian mimicry

Batesian mimicry is a form of mimicry typified by a situation where a harmless species has evolved to imitate the warning signals of a harmful species directed at a common predator...

 with sympatric adder

Viperinae

The Viperinae, or viperines, are a subfamily of venomous vipers found in Europe, Asia and Africa. They are distinguished by their lack of the heat-sensing pit organs that characterize their sister group, the Crotalinae. Currently, 12 genera and 66 species are recognized...

 species.

Behaviour

The viperine snake looks like an adder and behaves like one. It is known to strike like an adder but not bite. On the other hand, when in water, the viperine snake then looks like a grass snake and hunts its prey in the same way. The viperine snake should really be called the viper grass snake. In the small areas of England where it breeds in the wild it is usually mistaken for an adder

Adder

Adder may refer to:Snakes:* Any of several groups of venomous snakes of the Viperidae family including Vipera berus, the common European adder, found in Europe and northern Asia...

 and vice versa. This snake is diurnal.

Geographic range

The viperine snake is found in southwestern Europe and nothwestern Africa. Specifically, Natrix maura is found in the European countries of: Portugal

Portugal

Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

, Spain

Spain

Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

, France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

, northernwest Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 and even into Switzerland

Switzerland

Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

. It has spread to areas of England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 as well. It is found in African countries of Morocco

Morocco

Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

, northern Algeria

Algeria

Algeria , officially the People's Democratic Republic of Algeria , also formally referred to as the Democratic and Popular Republic of Algeria, is a country in the Maghreb region of Northwest Africa with Algiers as its capital.In terms of land area, it is the largest country in Africa and the Arab...

, northwestern Libya

Libya

Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....

, and northern to central Tunisia

Tunisia

Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area...

.

Description

Natrix maura is gray, brown, or reddish dorsally, with a black zigzag vertebral stripe, and lateral series of black ocelli with yellow centers. The labials are yellow with black sutures. It has a diagonal dark band on each temple, and another behind it on each side of the neck. Ventrally it is yellow or red, checkered with black, or all black.

The strongly-keeled dorsal scales are arranged in 21 rows. The ventrals are 147 -160; the anal plate is divided; and the paired subcaudals are 47-72.

Adults may attain a total length of 85 cm (33½ inches), with a tail 17 cm (6⅝ inches) long.

Habitat

The viperine snake is found in river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

s and lake

Lake

A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

s, and has also been recorded from areas of brackish water.