Decollate Snail

rumina decollata

The Decollate Snail, Rumina decollata, is a fascinating and often misunderstood terrestrial gastropod known for its unique shell and predatory habits. Unlike most garden snails that are herbivores, the Decollate Snail is primarily a carnivore, making it a valuable ally in gardens by preying on other pest snails and slugs. Its distinctive 'decollated' shell, which appears to have had its tip broken off, is a natural part of its growth process and aids in identification. This species plays an important ecological role in controlling gastropod populations, though it can also become a minor pest to certain cultivated plants if other food sources are scarce. Its adaptability has allowed it to establish populations in various regions worldwide.

Habitat: Found in gardens, agricultural fields, vineyards, orchards, and other disturbed areas with well-drained soil and abundant leaf litter or ground cover.

Appearance

The Decollate Snail has a distinctive conical shell, typically light brown to yellowish-brown, which can reach 2 to 5 cm in length. Its most striking feature is its 'decollated' apex; as the snail grows, the upper whorls of its shell are naturally shed, leaving a truncated, blunt tip. The body of the snail is grey to light brown, and it has two pairs of tentacles, with the upper, longer pair bearing eyes at their tips. The shell's surface is often glossy with fine growth lines.

KingdomAnimaliaPhylumMolluscaClassGastropodaOrderStylommatophoraFamilyAchatinidaeGenusRumina

Decollate Snail

Interesting facts

Decollate Snails can survive long periods of drought or cold by burrowing deep into the soil and entering a dormant state known as aestivation or hibernation, sealing themselves with a mucous plug.

The Decollate Snail earns its name because the upper, older whorls of its shell naturally break off as it grows, leaving a blunt or 'decollated' apex.

They are hermaphroditic, meaning each individual possesses both male and female reproductive organs, capable of self-fertilization or mating with another snail.

Unlike most garden snails, which primarily eat plants, the Decollate Snail is a natural predator, primarily feasting on other snails and slugs, making it a 'good guy' in many gardens.

Special abilities

This snail actively hunts and preys on other species of snails and slugs, making it a natural biocontrol agent. It uses its radula to consume its prey, often entering the shells of smaller snails.

As the snail matures, the older, apical whorls of its shell naturally break off, giving it a distinctive blunt appearance. This process, known as decollation, helps it adapt to burrowing and possibly sheds parasitic burdens.

Decollate Snails are capable burrowers, which allows them to seek refuge from heat, drought, and cold. They can aestivate (enter a dormant state during hot, dry periods) or hibernate in the soil, protecting them from adverse environmental conditions.

Measurements & details

Length: 2-5 cm
Weight: 0.001-0.005 kg
Lifespan: 2-4 years
Clutch Size: 20-200
Incubation: 10-40 days

Diet & Feeding

The Decollate Snail is primarily a carnivore, preying on other smaller snails and slugs. However, it is also an opportunistic omnivore, consuming decaying plant material and some live plants, especially when animal protein is scarce.

Age differences: Juvenile Decollate Snails initially consume more decaying plant matter and fungi, gradually shifting to a more carnivorous diet as they mature and grow larger.

Primary Foods

Garden snails (Helix aspersa)
Slugs (Deroceras reticulatum)
Snail eggs
Soft-bodied insects
Decaying plant matter

Foraging Method

Foraging

Ecological connections

hunts

Brown Garden Snail

Cornu aspersum

Main food source, particularly smaller or juvenile individuals.

hunts

Gray Field Slug

Deroceras reticulatum

Another primary food source for the Decollate Snail, especially slug eggs and smaller individuals.

eaten by

American Robin

Turdus migratorius

Predator that consumes snails, including Decollate Snails, when foraging in gardens.

competitor

Common Pill Bug

Armadillidium vulgare

Can be a competitor for resources like decaying plant matter, especially in areas with limited pest snail populations.

Traits

No trait badges are assigned for this object yet.

Also known as

No aliases listed yet.

Collections

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Safety

Danger

1/5 · Very low

No special safety notes yet.

Frequently Asked Questions

How to identify Decollate Snail?

The easiest way to identify Decollate Snail is to use the Snappit nature identifier app.

How long is Decollate Snail?

2-5 cm

How much does Decollate Snail weigh?

0.001-0.005 kg

How long does Decollate Snail live?

2-4 years

What does Decollate Snail eat?

Where is Decollate Snail usually found?

Found in gardens, agricultural fields, vineyards, orchards, and other disturbed areas with well-drained soil and abundant leaf litter or ground cover.

How does Decollate Snail hunt?

Foraging

How many eggs does Decollate Snail lay?

20-200