Reptiles
Sheltopusik
Pseudopus apodus · also called European glass lizard, Pallas's glass lizard, armoured glass lizard
Something the length of your arm and the thickness of a broom handle rustles out of a Balkan vineyard, moving like a snake through the grass. Then it blinks at you — and snakes cannot blink. This is a sheltopusik, the largest legless lizard in the world, and one of the most snake-like animals that is not a snake.
Overview
Pseudopus apodus is a legless lizard in the same family as the slow worm and the glass lizards. Adults reach 1 to 1.4 m, more than half of it tail, with a stiff, armour-plated brown body. It lives in dry grassland, scrub, and open woodland from the Balkans east across the Caucasus and the Middle East into Central Asia, and it hunts by day for snails, insects, and small vertebrates.
Not a snake
The giveaways are all there on close inspection: movable eyelids, external ear openings behind the eyes, a lizard-shaped skull with jaws that barely open wider than normal, and two tiny leg spurs beside the vent — the last trace of hind limbs. Because it cannot unhinge its jaws, it eats prey a snake of the same size would ignore, crushing snails with broad blunt back teeth.
Armour and a breakaway tail
Bony plates under the scales stiffen the trunk, and a fold of soft skin down each flank lets the body expand to breathe and feed. Grabbed by a predator, the sheltopusik sheds much of its tail, which thrashes as a decoy; the regrown tail is shorter and duller, so old animals often look stubby.
Status
The sheltopusik is Least Concern, widespread and often common. It declines locally where dry grassland is ploughed or built over, and many are killed on roads or by people who take it for a snake. It is hardy, long-lived, and a popular, easily tamed pet.
Sheltopusik: common questions
Is a sheltopusik a snake or a lizard?
A lizard, specifically a legless lizard in the family Anguidae, which also contains the slow worm and the North American glass lizards. It has lost its legs over evolutionary time, keeping only two tiny spurs near the vent, but it retains the internal features that define a lizard. It has eyelids that blink, so it can close its eyes, which no snake can do. It has open ear holes behind the eyes. Its jaw bones are fused at the chin and its skull is built like a lizard's, so it cannot unhinge its jaws to swallow large prey the way a snake does. It also autotomises its tail, dropping it to escape, which snakes generally cannot.
How big does a sheltopusik get?
It is the largest of the legless lizards. Adults are typically 1 to 1.2 metres in total length, and exceptional individuals reach close to 1.4 metres, with the tail making up more than half of that when it is intact. The body is as thick as a broom handle and heavily built, so a large sheltopusik has real bulk. This is much larger than the slow worm, which tops out around 45 to 50 cm, or the eastern glass lizard of the United States, which can be long but is far more slender.
What is the lateral fold along its body for?
The sheltopusik's back and belly are armoured with bony plates set under the scales, which makes the trunk rigid. A rigid tube cannot expand to breathe deeply, swallow a meal, or hold developing eggs, so the lizard has a solution — a groove of soft, granular, fold-in skin running the length of each flank. This lateral fold works like the pleats of an accordion, letting the body widen and narrow as needed without compromising the armour elsewhere. The same feature is present in the glass lizards and some other anguids.
Do people keep sheltopusiks as pets?
Yes, they are one of the more popular large lizards in the reptile hobby. They are hardy, tolerate a range of temperatures, are active and alert during the day, and become notably tame, often learning to take snails, insects, eggs, and pieces of meat directly from a keeper's hand. They can live for decades. The main drawbacks are that they need a large, secure enclosure with room to move and a substrate they can burrow into, and that a stressed animal will still drop its tail, which does not fully regrow. Wild collection for the trade is one local pressure on some populations.