The gastropods commonly referred to as snails and slugs belong to the group of soft-bodied animals referred to as mollusks which also includes oysters, octopus, cuttlefish, clams and squid. There are about 60,000 species of snails and slugs with varying shades of color. Both Slugs and snails thrive in damp soil or plant debris, and feed on living and decomposing plant material, but they prefer young, tender plant growth.
Both slugs and snails lay eggs in the spring and summer. They put the eggs in damp, protected places. Snails cover their eggs with soil. Snail and slug eggs are generally coated with a slimy substance that is slightly gummy. The eggs hatch in a few days. Snails and slugs can live for several years both in the wild and in captivity.
Slugs and snails share many common features and characteristics, however, the main difference between them is that snail carry a spiral shell on its back around with it and can withdraw its body into it when feeling threatened. Slugs on the other hand have no shell at all or more commonly the shell is reduced to a single flattish internal plate hidden inside the body.
What is a Slug?
Slug is a common name that is commonly used to describe any gastropod mollusk that does not possess a shell or has a shell that is reduced or the shell it possess is a small internal shell. Slugs generally secrete a layer of mucus for protection against predators. They have two sets of “sensors” or tentacles on their head and prefer cool, dull, and soggy places.
A slug can measure up to 15 inches in length, depending on the species. They can easily squeeze their body in small and narrow places like loose bark on the trees, logs on the ground and between rocks. Slugs may live up to 6 years in the wild and are hermaphrodites creatures which mean they have both male and female reproductive organs.
What You Need To Know About Slug
- Slug does not have an outer shell.
- It secretes a layer of mucus for protection against predators.
- Slugs vary in color from a light yellow to shades of gray and black and are often mottled with darker shades.
- Slugs are generally terrestrial.
- They thrive in damp soil or plant debris, retreating deep into the soil when the weather is dry.
- Slugs can be between 0.25 to 10 inches long, depending on the species.
- Types of slugs include: Grey field slug, keel slugs, chestnut slug, garden slugs, the large black slug, slender banana slug, California banana slug etc.
- Slug’s movement is more maneuverable and compressible.
- Slugs can survive 1 to 5 years in the wild.
- Slugs can easily squeeze their body in tiny places such as loose bark on the trees or rocks and logs on the ground.
What is a Snail?
Snail is a common name that is used when describing all gastropod mollusks that possesses coiled shells especially when they are in the adult stage.
There are a large number of species or types of snails that are generally categorized into three different groups: land snails, sea snails and freshwater snails. Although snails can be found in a wide range of habitats, they are usually found in agricultural lands where people grow crops or the regions with plenty of vegetation.
Snails move through a muscle which is known as a foot. They have one or more pairs of tentacles on their heads. A snail can measure up to 10 inches in length, depending on the species. They have a large number of microscopic tooth-like structures on their ribbon-like tongue called radula. They are mostly herbivores, so mostly feed on vegetation such as leaves, stems and flowers. Their natural predators include birds, rodents, amphibians etc.
They are hermaphrodite which means their body has both the sex organs: male and female reproductive organs. Around one month after mating, snails lay small white eggs on a covered leaf or into a burrow in the ground. Snails always remain attached to their shells so are not able to hide easily and usually find refuge within their own shell. Snails may live up to 2 to 3 years.
What You Need To Know Snail
- Snails have a hard, coiled, protective, exterior shell that it carries around on its back.
- It does not secrete any mucus; it uses its shell for protection against predators.
- Most snails are gray, but the shells can range from white to brown or almost black and be mottled or striped.
- Snails can be either terrestrial or aquatic creatures.
- They have much less options for hiding when weather is dry, so they usually find refuge within their own shell.
- Snails can be between 0.25 to 10 inches long, depending on the species.
- Types of snails include: Apple snail, garden snail, giant African land snail, Mediterranean green snail, orchid snail, roman snail etc.
- Snail’s movement is less maneuverable and compressible.
- Snails can survive 2 to 3 years in the wild and 7 to 8 years in captivity.
- Snails are permanently attached to their shells therefore they cannot easily squeeze their body through tiny spaces.
Also Read: Difference Between Turtle And Tortoise
Difference Between Slug And Snail In Tabular Form
BASIS OF COMPARISON | SLUG | SNAIL |
Outer Shell | Slug does not have an outer shell. | Snails have a hard, coiled, protective, exterior shell. |
Mucus Secretion | It secretes a layer of mucus for protection against predators. | It does not secrete any mucus; it uses its shell for protection against predators. |
Color | Slugs vary in color from a light yellow to shades of gray and black and are often mottled with darker shades. | Most snails are gray, but the shells can range from white to brown or almost black and be mottled or striped. |
Nature | Slugs are generally terrestrial. | Snails can be either terrestrial or aquatic creatures. |
During Dry Weather | They thrive in damp soil or plant debris, retreating deep into the soil when the weather is dry. | They have much less options for hiding when weather is dry, so they usually find refuge within their own shell. |
Length | Slugs can be between 0.25 to 10 inches long, depending on the species. | Snails can be between 0.25 to 10 inches long, depending on the species. |
Types | Grey field slug, keel slugs, chestnut slug, garden slugs, the large black slug, slender banana slug, California banana slug etc. | Apple snail, garden snail, giant African land snail, Mediterranean green snail, orchid snail, roman snail etc. |
Movement | Slug’s movement is more maneuverable and compressible. | Snail’s movement is less maneuverable and compressible. |
Lifespan | Slugs can survive 1 to 5 years in the wild. | Snails can survive 2 to 3 years in the wild and 7 to 8 years in captivity. |
Capability | Slugs can easily squeeze their body in tiny places such as loose bark on the trees or rocks and logs on the ground. | Snails are permanently attached to their shells therefore they cannot easily squeeze their body through tiny spaces. |
Similarities Between Slug And Snail
- Slugs and snails feed on living and decomposing plant material, but they prefer young, tender plant growth.
- They both move by gliding on a foot.
- They both consist of head with two pairs of tentacles and broad, muscular foot.
- Both are mostly nocturnal, but will step out on dark days or evening hours.
- Both prefer shady, damp areas with warm climate.
- Both snail and slug are classified as pests in many countries because they feed on plants and vegetations.
- Both snails and slugs can be used in human diet, but land snails are more popular and more frequently used.
- Slugs and snails are eaten by snakes, toads, turtles, beetles and birds.
- Snail and slug eggs are generally coated with a slimy substance that is slightly gummy.
- Both snail and slugs are hermaphrodites, which mean they can be both a female and a male.