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Origin of the myth
The expression "water viper" or "water asp" derives from the viperine snake's resemblance to the true viper: zigzag pattern on the back, triangular head, defensive behavior.
The true asp viper (Vipera aspis), although able to swim when necessary, is almost never found in aquatic environments.
Common aquatic snakes
In France and Europe, water snakes are mainly non-venomous snakes such as the viperine snake (Natrix maura), the ring-necked snake (Natrix natrix) and the tessellated snake (Natrix tessellata). These snakes live near water, swim very well, but are not vipers and pose no danger to humans.
How can you tell a viper from a snake?
To differentiate a viper from a snake, there are several reliable physical criteria, the most important of which is the shape of the pupil.
The pupil
- Vipers have a vertical pupil, like that of a cat.
- Garter snakes have a round pupil.
Head shape
- Adders have a triangular, flattened head.
- Garter snakes have oval or rounded heads, which may appear more elongated.
Scales on the head
- Viper: numerous small scales.
- Snake: large, flat scales, "armored" appearance.
The tail
- Viper: short tail with abrupt end.
- Snake: long, tapering tail.
Body size and shape
- Viper: stocky body, rarely over 80 cm.
- Snake: slender, slender body, can exceed 1 meter depending on the species.
Venomosity
Adders are venomous, while garter snakes are generally harmless to humans (with rare exceptions such as the Montpellier garter snake, whose bite is not serious).
To remember
The most reliable feature observed from a distance remains the shape of the pupil. Other characteristics (head, tail, scales) may vary according to age or species, but remain good clues for identification.
In short, there is no such thing as a true "water viper", only water snakes, sometimes mistaken for vipers because of their appearance.
