About Zamenis scalaris (Schinz, 1822)
The ladder snake, scientifically named Zamenis scalaris (Schinz, 1822), is a medium-sized species. It reaches a maximum total length including the tail of around 160 cm (63 in), with an average total length of 120 cm (47 in). It has a pointed snout and a dark eye. Adult ladder snakes show less variation in appearance than many related snake species. Dorsally, their base color ranges from yellowish to dark brown, with two darker stripes running the full length of the body from neck to tail. They usually also have a dark stripe running from the back of the eye to the corner of the jaw, and sometimes have subtle darker markings on their sides. Their ventral side is pale, ranging from silvery-grey to whitish, with occasional dark spots. Juvenile ladder snakes have lighter, brighter coloration that ranges from yellow to light brown, with a characteristic black "ladder" pattern along their upper side. Their pale underside has black markings that sometimes merge to cover the entire underside. As ladder snakes age, these juvenile colors and patterns fade, leaving the simpler, solid pattern of adults. The ladder snake's geographic range covers Portugal, Spain, southern France, and extends just into Italy. It is also found on Menorca and the Iles d'Hyères off the coast of Provence. It is absent from northern Iberia, including most of the Pyrenees, Galicia (though it does occur on Ons Island, part of the Atlantic Islands of Galicia National Park), Cantabria, and the Basque Country. The population of ladder snakes on Menorca may have been introduced by humans. This species favors areas with scrubby, bushy cover, including orchards, vineyards, hedges, and overgrown dry-stone walls, and it is common in maquis habitats. It prefers habitats with stones and boulders and low shade. While ladder snakes have been recorded at altitudes over 2,000 metres (6,600 ft), the species most commonly prefers altitudes ranging from sea level up to 700 metres (2,300 ft).
