Slow Worm or Snake: The Complete Guide

Everyone knows what a Snake looks like: a legless reptile with a long, sinuous body. But did you know that there is an animal with exactly the same description, but which is not a snake? 😮

This strange animal is known as the Slow Worm. In this article, we offer you a complete portrait of this reptile too often confused with a snake.

1) The Anguis Fragilis, or Fragile Slow Worm

A) A Lizard Snake?

The slow worm, scientifically known as Anguis Fragilis ("fragile"), is a species of saurian belonging to the Anguidae family. It is neither a worm nor a snake, although it is often confused with the latter ❌. It is in fact a lizard that has evolved over time to become legless (it is therefore apodous). However, it retains remnants of legs, only visible by X-ray.

It is sometimes called the "Glass Snake" because of its fragility. It is an ectothermic reptile: it depends on the ambient heat to maintain its body temperature 🥵/🥶. In English, it is known as the "Slow Worm", even though the slow worm is not a slow animal!

Like the snake, the slow worm periodically sheds its skin throughout its life. It is a long-lived species, with individuals surviving up to 30 years in the wild, while one individual in captivity lived to the age of 54! 😅

B) Slow Worm: Color and Size

This strange lizard that looks like a snake because it has no legs, can reach a size of 50 cm for the largest females. Half of its size is made up of its tail. It has a small head in the extension of its body. Its head is conical with a rounded nose, and small eyes with eyelids 👁️. The body of the slow worm is covered with smooth and shiny scales and the coloring varies from silver gray to coppery bronze. This gives the body of the reptile an almost glassy appearance and facilitates its movement in the ground.

Males sometimes have bluish spots on the sides of their body, and have a pale belly. Females normally have a black or dark line that extends the entire length of their back, and a dark belly. Males also have proportionally larger heads. This variation between the sexes is known as sexual dimorphism.

Slow worms in the juvenile stage are very thin and initially measure about 4 cm long 📏. The young have a black belly and golden or silvery sides, sometimes with a stripe along the entire length of the body if they are females.

How can you tell the difference between a slow worm and a snake?

Telling the difference between a slow worm and a snake can be tricky at first glance, as both are legless and slither. However, there are key differences:

1. Eyelids: Slow worms have movable eyelids and can blink, while snakes have a transparent scale (spectacle) covering their eyes and cannot blink.

2. External Ear Openings: Slow worms have small ear openings on the sides of their heads, which snakes lack.

3. Body Texture: Slow worms have smooth, shiny, almost metallic skin, whereas snake scales are more textured and less shiny in many species.

4. Tongue: Slow worms have a broad, forked tongue, but it is much shorter and less noticeable compared to the long, thin, deeply forked tongue of a snake.

5. Movement: Slow worms move more slowly and with a more rigid, less fluid motion, while snakes tend to be faster and more sinuous in their movements.

6. Tail: Slow worms have a very long tail that can break off as a defense mechanism (autotomy), while snakes do not have this ability.

These features help distinguish slow worms as legless lizards rather than snakes.

It's your lucky day! From now on, you too can wear these magnificent Snake Pendant

2) Identify and Recognize a Slow Worm

A) Slow Worm or Viper?

The slow worm is differentiated from the snake by several anatomical characteristics:

• The slow worm is generally smaller than a snake.
• Unlike snakes, slow worms have eyelids: they can therefore blink. 😉
• Slow worms have an opening that serves as their external ear (auricular opening).
• They can separate from their tail to escape a predator, which no snake is capable of doing.
• They have a short and partially forked tongue which, unlike snakes, cannot come out of a closed mouth.

Measuring up to 50 cm long, a slow worm is often smaller and thinner than our common snakes in France (such as the grass snake), which easily reach a meter long 🔍. When it comes to differentiating slow worms from French vipers, the color of the scales and the shape of the head leaves no room for doubt as the difference is so significant. If you want to know how to Identify a Snake, we have written a very comprehensive article on the subject! After reading this article, Slow worm or Grass Snake: impossible to confuse!

B) Slow Worm Molting

An adult slow worm is covered in small, smooth, shiny scales that do not overlap, unlike many species of snake 🐍.

When molting, the skin of slow worms peels off in several sections rather than along its entire length, as is the case with snakes. This is important because whether they are snakes or slow worms, these reptiles are generally very discreet: you have to look for them to find them! The main clue to their presence can sometimes be a simple molt. It is therefore advisable to know which animal the molt belongs to, to know who you are dealing with. 🧐

How to tell if a slow worm is pregnant?

Telling if a slow worm is pregnant (gravid) requires careful observation, as their external signs are subtle. Here are some ways to identify a gravid (pregnant) slow worm:

1. Swollen Abdomen: A pregnant slow worm will have a noticeably thicker, more rounded midsection. The swelling is often more pronounced toward the back half of the body, where the eggs or developing young are located.

2. Lethargy: Gravid slow worms may become slower and less active than usual, conserving energy for reproduction.

3. Behavior Changes: A pregnant slow worm might spend more time basking in the sun to raise its body temperature, which aids in the development of the embryos.

4. Visible Bulges: In some cases, especially closer to giving birth, you might see slight bulges along the sides of the slow worm’s body, indicating the presence of developing young.

5. Timing: Slow worms typically breed in spring or early summer, with gestation lasting several months. If you observe a slow worm during late summer, there’s a higher chance it could be gravid, as they give birth to live young (not eggs) around this time.

It's important to handle or observe slow worms with care, as undue stress can harm them or their developing offspring.

3) Is the Slow Worm Dangerous?

A) The Slow Worm and its Dreaded Bite... or Not!

Have you found a monstrous snake in your garden? Wait a minute, it could be just a harmless slow worm! 😮

The slow worm is unfortunately far too often a victim of its resemblance to snakes. Every year, many people who come across it in the forest, in their garden or near their house, attack this friendly animal, thinking that it is a fearsome venomous snake.

However, although the slow worm can theoretically bite with its small sharp teeth, it does not pose a threat to us ✔️. In fact, the slow worm has no venom, it is completely harmless and poses no danger to humans.

It's your lucky day! From now on, you too can wear these magnificent Snake Pendant

B) A Slow worm, No Danger!

Not very fearful, the slow worm is much less sensitive to ground vibrations caused by footsteps than snakes. While the latter run away as soon as something approaches them 💨, the slow worm is less fearful as long as we do not try to catch it. But this is rather a fault for him because it is not uncommon for children to try to catch and handle him, even if it means seriously injuring him. Cats are particularly fond of them 😺. Although the slow worm is not dangerous for cats, our small pets risk injuring or killing him by playing with him.

Where do slow-worms live in the UK?

4) Slow worm of Usa and Elsewhere 

    The slow worm is present in a large part of Europe: from Great Britain, southern Scandinavia and the Iberian Peninsula eastward to Greece, Turkey and the countries bordering the Black Sea 🌍. It is also present in the Baltic states of Estonia (Balkan Slow Worm), Lithuania and Latvia, Russia, northern Iran and parts of North Africa, including Algeria and Tunisia. The species is absent from many islands in the Mediterranean, and from Ireland.

It is the most commonly seen reptile in the UK 🔎. The only other member of the family, the Peloponnesian Slow Worm (Anguis cephalonnica), is very common in some parts of Greece.

The slow worm, a legless lizard often mistaken for a snake, is primarily found in Europe and parts of Asia, but its relatives can be found in the USA and other regions as well. While the true slow worm (Anguis fragilis) does not naturally occur in the United States, the country's legless lizards, such as the California legless lizard (Anniella pulchra), share similar characteristics. These creatures thrive in diverse habitats, from woodlands to coastal dunes, where they burrow in the soil and feed on insects and small invertebrates. Globally, slow worms and their relatives are fascinating examples of evolutionary adaptation, showing how legless lizards have emerged in various forms and environments. Despite their snake-like appearance, slow worms are harmless to humans and play a vital role in controlling pest populations across the world..

How to identify a slow worm?

Identifying a slow worm involves noting several distinct features. Here’s how you can recognize a slow worm:

1. Appearance: Slow worms have a smooth, shiny, and cylindrical body that is often mistaken for a snake. They can range in color from brown to grey, sometimes with a metallic sheen, and may have a hint of a golden or bronze hue.

2. Size: They typically measure between 30 to 50 cm (12 to 20 inches) in length, though some can grow slightly longer.

3. Eyelids: Unlike snakes, slow worms have movable eyelids. If you see a creature blinking, it's likely a slow worm rather than a snake.

4. External Ear Openings: Slow worms have small, visible ear openings on the sides of their heads, while snakes lack these features.

5. Tongue: A slow worm’s tongue is broad and forked but shorter than that of most snakes. Snakes generally have a longer, deeply forked tongue.

6. Body Texture: The skin of a slow worm is smooth and shiny, in contrast to the often more textured scales of snakes.

7. Tail: Slow worms have a relatively long tail compared to their body size, and it can detach as a defense mechanism (autotomy). This is different from most snakes, which cannot regrow a lost tail.

8. Behavior: Slow worms are generally slower-moving and more sluggish compared to the more agile and faster movements of many snakes.

By paying attention to these characteristics, you can accurately identify a slow worm and differentiate it from other legless reptiles.

It's your lucky day! From now on, you too can wear these magnificent Snake Pendant

5) Slow Worm and its Habitat

A) Where to Find Slow Worms?

Slow Worms can be found in a wide range of habitats:

• Forest edges 🌳
• Moorland
• Hedgerows
• Dense meadows
• Unmown grassy meadows
• Gardens
• Wasteland
• Hedgerows

It is often found in compost heaps as it benefits from the heat generated by decaying vegetation and feeds on the slugs and snails that also live there. Although it is diurnal (meaning it is active during the day ☀️), it is a fairly secretive species that spends most of the day out of sight under stones or pieces of wood, or in a burrow dug in the ground. It may sometimes come out at dusk or after a shower in order to hunt.

B) How to Find Slow Worms?

Although they generally prefer humid habitats with dense vegetation around them (ditches, piles of leaves, ...), slow worms can be seen in dry and warm weather, if there is enough shade. When the weather is suitable, you can sometimes find a slow worm basking in the sun on the grass or on a stone 😎. But unlike other reptiles, slow worms do not often sunbathe outdoors. Instead, they prefer to hide under logs or metal sheets, in order to stay safe from potential threats.

The slow worm is mainly found in places where the soil is soft, because it is a semi-burrowing species. It can bury itself more than a meter deep during the bad season. ⛏️

6) Predators of the Slow Worm

A) The Slow Worm as Food

Like most animals, the slow worm has its own natural predators and parasites. And this has an influence on the life of these small reptiles, and on the evolution of the entire species.

In France, the slow worm is a potential prey for various animals:

• Snakes (grass snakes and vipers) 🐍
• Hedgehogs 🦔
• Badgers 🦡
• Red Fox 🦊
• Rats 🐀
• And of course a wide variety of birds ( Crow, Pheasant, ...) and birds of prey 🦅

But such a small lizard obviously has many other potential predators not mentioned here, such as cats and all kinds of rodents in urban areas.

The slow worm is not spared by parasites 🦠. There are two main common endoparasites (or internal parasites) that can infect the slow worm in Europe. These are two nematodes, also called "roundworms"; that develops in the gastrointestinal tract of their host 😨: Neoxysomatium brevicaudatum and Entomelas entomelas. In the rest of the world where the slow worm is present, 7 different species of parasitic worms have been observed in this reptile.

B) The Slow Worm and its Severed Tail

Like many lizards, the slow worm has a defense mechanism against predation, by which it loses its tail when threatened by a predator 😯. The scientific name for this process is autotomy. It occurs when the slow worm squeezes a muscle that breaks one of the tail vertebrae in two. The detached tail wiggles and contracts, distracting the predator and allowing the reptile to escape.

A new tail will later grow in its place, although it will be shorter than the original 😕. The term "fragilis" (fragile) which makes up the scientific name of the slow worm, comes from this ability to sacrifice its tail to protect the rest of its body from predation.

The most telling example to illustrate this ingenious defense mechanism is when a bird tries to eat the slow worm. When a bird tries to catch it, the slow worm "freezes". If the bird starts to peck at it, it will remain completely still, and will detach its tail from its body. The severed tail can wriggle for a few minutes. The bird then generally grabs the tail and flies away, letting the reptile escape.🏃‍♂️

What is the lifespan of a slow worm?

Slow worms can live for up to 10-15 years in the wild. Their lifespan can vary depending on factors such as habitat quality, food availability, and predation.

7) What Does a Slow Worm Eat?

Slow worms search for food in two stages. Very early at dawn, then as night approaches 🌙. These reptiles hunt at such times to avoid predators.

Slow worms are carnivorous and have a very varied diet: slugs and invertebrates 🐌, spiders, beetles, insects, larvae, snails, earthworms, ... They could even eat up to 50 slugs a day! That's why gardeners love them, just as farmers love earthworms.

This reptile has curved and pointed teeth towards the back that allow it to firmly hold its prey, such as slugs, which are moist and slippery to the touch 🤢. The slow worm's tongue is serrated rather than forked as is the case with snakes. It allows it to have an excellent sense of smell.

The slow worm obviously needs water to survive 💧. Usually, dew or small puddles of water are enough for it.

It's your lucky day! From now on, you too can wear these magnificent Snake Pendant

8) Slow worms and Hibernation

Around October, slow worms burrow into the ground, find a crevice in a rotting tree stump, or a cozy pile of leaves in order to spend the winter 🥶. In cold-blooded reptiles, this is called brumation. This is not a true hibernation, because here the creatures do not fall asleep as deeply. But it is a way to save their energy during the colder months, when food is scarce.

This period generally lasts from October to March. Slow worms can "hibernate" alone, or in groups with other slow worms. Such groups can bring together more than 100 specimens 😅.

After emerging from hibernation in March, slow worms can be observed again as they prepare for breeding in May.

9) Slow worm and Reproduction

Breeding in slow worms occurs in the spring, shortly after emerging from hibernation 💤. It begins in May and the young are usually born in late summer. Violent fights can occur between males, and serious injuries can be inflicted with their small teeth.

Courtship occurs when a male bites and holds a female by the head or neck, and the pair intertwine their bodies, sometimes for several hours.

Slow worms do not lay eggs, they are an ovoviviparous species. They incubate their eggs in their bodies and give birth to between 5 and 20 babies 👶. Each young measures between 5 and 10cm. The gestation period is about 3 months. The babies are born in a sticky egg sac, which opens shortly after leaving the mother's body.

Slow worms grow relatively slowly ⌚. It takes 6 to 8 years for an individual to reach its adult size. Males reach sexual maturity after 3 to 4 years while females take 4 to 5 years to become capable of reproducing.

It's your lucky day! From now on, you too can wear these magnificent Snake Pendant

10) Threats and Protections for Slow Worms

A) The Slow Worm: an Endangered Species

Slow worms are protected by law in France ⛔. The latter prohibits the intentional killing, injury, sale or exchange in any way.

Although widespread and widespread in France (and in most European countries), the overall slow worm population has declined 📉. And this is mainly because of the transformation of its habitat: increasing urbanization is causing the disappearance of some of the slow worm's natural habitats.

Slow worms are very sensitive to pesticides and insecticides used massively by the food industry. These toxic substances are found in large quantities in soils, and in the invertebrates that the slow worm feeds on ☣️. Generally speaking, the slow worm is vulnerable to soil pollution, whether chemical or radiological (incidents at nuclear power plants such as the Chernobyl cloud).

Finally, slow worms are victims of their resemblance to snakes. Many people still kill these harmless reptiles when they come across them because they mistake them for dangerous snakes due to a lack of knowledge. 😡

B) Slow Worm Protection

The French committee of the IUCN (International Union for Conservation of Nature) classifies slow worms as being of Least Concern 🤔. But because they are a common and widespread species, the slow worm is not considered to be at risk internationally and is not on the IUCN International Red List of Threatened Species.

In the UK, however, the slow worm is protected under Schedule 5 of the Wildlife and Countryside Act, which prohibits the intentional killing, harming or sale of the species 👍. It has also been added to the UK Biodiversity Action Plan and the Scottish Biodiversity List as a priority species for conservation, due to its population decline due to habitat loss.

It is therefore best not to attempt to capture a wild slow worm. The best thing to do if you find one is to leave it where it is (and put the stone it was under back in place!).

11) A Slow Worm in my Garden!

A) How to Attract Slow Worms to Your Garden?

Are you passionate about reptiles and would you like to be able to observe wild slow worms in your garden? It's possible 😀! There are a few little tips to put in place to make your garden pleasant and attractive to these little creatures:

Do not cut the grass too short. This way, you will have a more diverse flora, therefore a denser fauna. And who says insects and invertebrates, says pantry for slow worms! 🍽️
Avoid turning over the soil. As you now know, slow worms can dig galleries. By turning over the soil over a large area and a significant depth, you risk disturbing these poor little reptiles and making them flee.
Do not use pesticides and chemical weedkillers. These products are toxic to the slow worm (and to your garden in general ☠️), which can be contaminated via the slugs and worms it feeds on.
Leave a corner of the garden "wild": a small space that you do not maintain and where you place stones and branches. The perfect place for slow worms!
Watch your cat when it stays outside too long: it might have found a poor slow worm to "play" with...
By putting all these tips in place, you maximize your chances of being able to observe slow worms at home 🔎! But don't forget that these animals are very discreet and are not found in equal numbers in all regions.

B) How to Catch a Slow worm?

As you can see, French law prohibits capturing a slow worm to put it in a terrarium, harm it, or sell it. We're not going to tell you how to make a slow worm trap, or how to set up a terrarium for this little beast ❌.

However, as reptile lovers, it is not forbidden to help a slow worm in a bad situation: a specimen too close to a road, cornered with your cat trying to catch it, stuck somewhere, ...

To handle a slow worm and avoid an unenviable end, here are some tips:

• Make sure it is a slow worm, and not a snake. It may seem silly, but you can never be too careful. 😅
• Don't grab it by the tail (gently press its head to the ground to catch it)
• Hold it gently
• Don't squeeze it between your fingers or hands
• Let it slip between your fingers to release it.

That concludes this article on the slow worm, this very special legless lizard! 🙂

It's your lucky day! From now on, you too can wear these magnificent Snake Pendant

If you've read this far, it's because like us, you must be passionate about reptiles! Snake Label® is a shop opened by two terrarium enthusiasts. We believe that the world of reptiles is not something reserved for a small group of enthusiasts, and deserves to be highlighted.

We created Snake Label® with the aim of democratizing this passion for reptiles. If you're a fan of snakes, quickly discover our sublime Snake Rings, our impressive Snake T-Shirts, or our giant and colorful  accessories.! 🐍

Our products are aimed at enthusiasts as well as fashion and originality enthusiasts. Snake-shaped jewelry can be very glamorous, or on the contrary symbolize the strength and aggressiveness of their wearer 💪. The Symbolism of the Snake being very strong, our snake jewelry is ideal if you like to give meaning to your adornments. As for our clothes, they are ideal if you want to stand out!

Style or Power: choose the meaning of the snake that suits you best!

Dive into the fascinating world of snakes and explore our other articles now!

Stay Updated!
Don't miss out on the latest insights, tips, and exclusive content. Subscribe to our blog newsletter today and be the first to know about new posts, special offers, and more!
Join our community now—just enter your email below to stay connected.