The slow worm is neither slow, nor a worm, nor a snake
Europe's slow worm looks like a small snake, yet it is a legless lizard that blinks with movable eyelids. Even its name misleads: the slow part comes from an Old English word for earthworm. One male lived at Copenhagen Zoo from 1892 to 1946, possibly making the species the longest-lived lizard known.
Several features betray its lizard identity. Snakes have fused, transparent eyelids, while slow worms can close their eyes. They also lack the notch in the upper lip that lets a snake flick its tongue with its mouth shut, so a slow worm must part its jaws slightly to taste the air. Bony plates called osteoderms under its smooth, non-overlapping scales make it move far more stiffly than a snake. Its old nickname blindworm is wrong too, since its small eyes work perfectly well.
Adults typically measure 40 to 45 centimetres, with the tail often a little longer than head and body combined. Like many lizards it can shed that tail when grabbed by a predator, but the replacement grows back only as a short stub, perhaps because losing the tail barely affects how it moves, feeds or defends itself. In the wild it may live around 30 years. Females carry eggs internally for 11 to 14 weeks and usually produce eight to twelve young, which break out of a thin transparent shell just after birth, each weighing under a gram.
Rather than basking in open sun, slow worms warm themselves under rocks, logs or sheets of metal heated by the sun. British gardeners sometimes lay out black plastic or tiles to attract them, since they eat slugs, snails and earthworms. Foxes, badgers, hedgehogs, adders, crows and domestic cats all hunt them. In Britain they are protected, and killing or selling one has been illegal since the Wildlife and Countryside Act 1981.
What was once a single species has been split into five, from western Europe to the Peloponnese. The genus itself dates back to the Eocene, between 43.5 and 41.2 million years ago.
Source: Common slow worm
