Natrix maura is a natricine water snake of the genus Natrix. Its common name is viperine water snake or viperine
snake. Despite its common names, it is not a member of the Subfamily Viperinae. This nonvenomous, semiaquatic, fish-eating snake was given its common names due to behavioural and aesthetic similarities with sympatric adder species.
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. This snake is diurnal.
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.
Snake Adults may attain a total length of 85 cm (33½ inches), with a tail 17 cm (6⅝ inches) long