White Garden Snail
Phylum: Mollusca, Class: Gastropoda, Order: Stylommatophora, Family: Helicidae, Genus: Theba, Species: T. pisana · Helicidae (Typical Garden Snails) · Gastropod land snail, whole shell, globular spiral shape
Species
Theba pisana
Shell Type
Gastropod land snail, whole shell, globular spiral shape
Family
Helicidae (Typical Garden Snails)
Size
Approximately 18-20 millimeters in diameter, which is typical for an adult of this species whose range normally spans 12-25 millimeters.
Color & Pattern
Uniform chalky white to off-white appearance due to sun-bleaching or fading, obscuring the usual brownish or yellowish spiral bands and markings characteristic of live specimens. The surface is matte with fine growth lines.
Rarity
Very Common, often considered an invasive agricultural pest in regions outside its native range.
Habitat
Terrestrial habitats, commonly found in open country, sand dunes, agricultural fields, and coastal gardens. They are land snails, thriving in warm, dry climates.
Geographic Range
Native to the Mediterranean region, but introduced widely across Western Europe, parts of the British Isles, Australia, South Africa, and North America.
Description
A small, globular, solid terrestrial snail shell featuring a low spire and rounded whorls. The surface displays delicate, incised growth lines giving it a subtle texture. The aperture is roughly circular to lunate, and the umbilicus is mostly or entirely covered by the columellar reflection.
Key Features
Globular shape with a low spire, solid construction, fine growth striae, and a closed or nearly closed umbilicus, distinguishing it from other similar small land snails.
Collector Value
Low collector value. While widely available and easy to find, they are rarely sought after by serious shell collectors unless documenting introduced land snail species.
Condition Notes
Good overall structural integrity with no major breaks or cracks, though the shell is completely bleached white with loss of its original banding pattern. Collectibility grade is Fair due to the worn and faded coloration.
Interesting Facts
Theba pisana is known for aestivating, a form of summer dormancy where they seal themselves to plant stems, rocks, or fences in large clusters to survive hot, dry conditions.
Ecological Role
Acts as a herbivore feeding on various living and decaying plant matter. In agricultural areas, they can become significant pests damaging crops, and they serve as a food source for various birds, rodents, and small mammals.
Similar Species
Helix aspersa (Garden Snail) which is significantly larger, and Cernuella virgata (Striped Garden Snail) which typically retains more pronounced dark banding.
Beach Finding Tips
Not found on beaches; instead, search terrestrial environments such as coastal sand dunes, low-lying coastal vegetation, and garden walls during dry seasons when they cluster together.