Slow wormAnguis fragilis — habitat, diet and reproduction

Glossy copper-brown legless slow worm coiled on a rock

Slow worm (Anguis fragilis) coiled on a rock. · Hans Hillewaert / CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0). Cropped and resized.

The slow worm looks like a small, shiny snake but is actually a legless lizard. Unlike snakes, it blinks and can shed its tail to escape predators. It is completely harmless and feeds mainly on slugs and earthworms.

Quick facts

Common name	Slow worm
Scientific name	Anguis fragilis
Lifespan	Can exceed 20 years; over 50 years in captivity
Length	Usually 40–50 cm
Diet	Carnivore: slugs, earthworms, insects, spiders
Predators	Birds, hedgehogs, snakes, foxes, badgers and cats
Conservation status	Least Concern (LC)
Distribution	Europe and western Asia
Habitat	Woodland edges, clearings, gardens and damp grassland
Family	Anguidae
Reproduction	Gives birth to live young

Primary category:Reptiles
Explore this animal's categories:
Animals of Asia Animals of Europe Animals of Romania Animals of Romania’s forests Animals of Romania’s gardens and parks Animals that regrow body parts Camouflaged animals Carnivores Hibernating animals Live-bearing animals Reptiles Reptiles and amphibians of Romania S Scaled animals Vertebrates Wild animals

Interesting facts

The slow worm has eyelids and blinks, something snakes cannot do.
It is one of the longest-lived lizards; in captivity one lived over 50 years.
It has no venom and cannot harm a person.
A shed tail wriggles for minutes, distracting the predator.

Characteristics

The slow worm has a smooth, glossy, cylindrical body with no visible legs. Small, tightly fitting scales make it look like polished metal. It is usually brown, copper or grey.

Females often have dark sides and a thin line on the back, and some males show blue spots. Young are gold or silver with a dark back stripe. Eyelids, small ear openings and a breakable tail separate it from snakes.

Behaviour

It is slow and secretive, spending much time under stones, logs, leaves or boards on the ground, where it finds moisture and food.

It emerges mostly in the morning, evening and after rain, when slugs are active. In winter it hibernates in groups in burrows or under roots, sometimes with other reptiles.

Habitat and distribution

The species lives across much of Europe. Recent genetic research places populations in eastern Europe, including much of Romania, in a very similar species, Anguis colchica.

In Romania it occurs from lowlands to mountains, in open woods, clearings, damp grassland and gardens.

Diet and feeding

The slow worm eats mostly slugs and earthworms, plus soft insects, larvae and spiders.

Its small, backward-curving teeth suit soft, slippery prey, making it a useful ally in gardens where slugs damage vegetables.

Reproduction and life cycle

The slow worm lays no eggs. Eggs develop inside the female, and live young are born in late summer.

A female usually gives birth to 6–12 young a few centimetres long, independent from birth. Slow worms mature slowly, after several years.

Name and history

The scientific name Anguis fragilis means “fragile snake”, after the easily broken tail.

In Romanian, the name “năpârcă” is sometimes wrongly used for vipers. The belief that it is venomous has led to many needless killings. The adder is easy to tell apart: the slow worm is smooth and glossy, with no zigzag pattern.

Conservation and threats

The slow worm is assessed as Least Concern and is still widespread in Europe.

Main threats include cats, slug pellets, mechanised mowing and killing through confusion with snakes. Log piles, stones and leaf heaps in gardens offer shelter. Like all wild reptiles in Romania, it is protected.