The geographic range of the ladder snake includes Portugal, Spain, southern France and just into Italy, also Menorca and the Iles d'Hyères off Provence, but it is absent from northern Iberia including much of the Pyrenees, Galicia (although the species is found on Ons Island, in the Atlantic Islands of Galicia National Park[3]), Cantabria and the Basque Country.

[1] The ladder snake enjoys scrub bushy cover, including orchards, vineyards, hedges and overgrown dry-stone walls; it is common in the maquis.

It normally also has a dark stripe running from the rear of the eye to the angle of the jaw and sometime subtle, darker markings on the sides.

The juvenile snakes have lighter and brighter colouration, varying from yellow to light brown, with the characteristic “ladder” pattern picked out in black along the upperside.

Juvenile ladder snakes prefer small lizards, baby rodents, spiders, and grasshoppers.

Any attempt to pick up a ladder snake may be greeted by sharp bites and also the emptying of the cloacal glands, releasing an offensive odour.

[4] It is a more mobile snake than many of its relatives and movements of up to 100 m per day have been recorded, while the average home territory of an individual is 4,500 m2.