Garden snail

Cornu Aspersum or otherwise going by the common name of garden snail, it is likely the most widely known species of all terrestrial mollusks. It is in the family Helicidae which includes many of the most common land snails. It used to be under the classification Helix Aspersa, however the newer classification groups it into the genus Cornu

It is widely regarded as a garden pest due to its accidental introduction into many areas, however in some parts of the world it is also desired as a food item.

Taxonomy

Kingdom: Animalia

Phylum: Mollusca

Class: Gastropoda

Order: Stylommatophora

Family: Helicidae

Genus: Cornu

Species: Cornu Aspersum

Description

Adults have a thin but hard calcareous shell that can be between 1-1.5 inches in diameter and 1-1.375 inches high. Their shells can vary in color and shade but are typically a reticulated pattern of dark brown, brownish-golden, or chestnut with yellow stripes, flecks, or streaks. The body of the garden snail is soft, slimy, and brownish-gray in color. Its soft body is able to be fully retracted into its shell which it does whenever it is inactive and or feels threatened. Another mechanism it uses when threatened or injured or badly irritated, the snail produces a defensive froth of mucus that might repel some enemies or overwhelm aggressive small ants and other bugs of that nature.

Unlike other species within the class gastropoda, garden snails do not have a operculum which is a type of seal certain mollusks use in order to keep in moisture and for defense from small predators. Instead during dry or cold weather garden snails seal the aperture of the shell with a thin membrane of dried mucus; the term for such a membrane is epiphragm.

Life Cycle and Reproduction

Members of Cornu aspersum are hermaphrodites, meaning they produce both male and female gametes. Because of this reproduction is usually sexual however self-fertilization can sometimes occur. These mating sessions often taken several hours in which sperm is shared; garden snails are also one of the species that use "Love Darts" in mating.

Two weeks after this fertilization garden snails lay around 80 spherical white eggs into little spaces within topsoil or even under spaces under rocks. Within the span of a year a garden snail can lay around six batches of eggs. The eggs are about 4mm in diameter. Upon hatching young garden snails take one to two years to reach maturity and begin the reproductive cycle all over.

Habitat

Cornu aspersum is native to the Mediterranean region and its present range stretches from northwest Africa and Iberia, eastwards to Asia Minor and Egypt and northwards to the British Isles. However there is an increasing non-native distribution to other countries in the world such as Australia, North America, Costa Rica, and South America. Due to being deliberately or accidentally introduced into various regions nowadays it is cosmopolitan in temperate zones, and has become naturalized in regions with climates that differ from the Mediterranean climate in which it evolved.

Human Importance

The common garden snail is known for many reasons in relation to humans.