Many subspecific varieties have been described on the basis of shell characters (e.g. It also still remains an arguable position to retain Helix as the generic name. aperta as being in different genera, call the former Cryptomphalus aspersus. Other workers, including Ukrainian and Russian research teams, who regard H. ![]() Until this was established, Italian research teams and others used the generic name Cantareus instead. Previously there was debate whether Cornu was a valid generic name (because it was first applied to teratological specimens), but a 2015 ruling has confirmed that it is so. One such genus is Cornu, which is appropriate if the species is considered as congeneric with the species previously known as Helix aperta. However, in a number of publications since 1990, it has instead been placed in various genera previously considered as subgenera of Helix. The accepted name of the species was long considered to be Helix aspersa, a member of the genus Helix. The shell of Cornu aspersum is almost always right-coiled, but exceptional left-coiled specimens are also known see Jeremy (snail) for an example. The mouth is located beneath the tentacles, and contains a chitinous radula with which the snail scrapes and manipulates food particles. The snail extends the tentacles by internal pressure of body fluids, and retracts all four tentacles into the head by invagination when threatened or otherwise retreating into its shell. The head bears four tentacles the upper two are larger and bear eye-like light sensors, and the lower two are tactile and olfactory sense organs. These mechanisms allow Cornu aspersum to avoid either fatal desiccation or hydration during months of either kind of quiescence.ĭuring times of activity the snail's head and "foot" emerge. The snail also has an osmoregulatory mechanism that prevents excessive absorption of water during hibernation. During aestivation, the mantle collar has the ability to change its permeability to water. When overwintering, Cornu aspersum avoids the formation of ice in its tissues by altering the osmotic components of its blood (or haemolymph) this permits it to survive temperatures as low as −5 ☌ (23 ☏). The snail's quiescent periods during heat and drought are known as aestivation its quiescence during winter is known as overwintering. The epiphragm helps the snail retain moisture and protects it from small predators such as some ants. It has no operculum during dry or cold weather it seals the aperture of the shell with a thin membrane of dried mucus the term for such a membrane is epiphragm. When injured or badly irritated the snail produces a defensive froth of mucus that might repel some enemies or overwhelm aggressive small ants and the like. The body is soft and slimy, brownish-grey, and able to be retracted entirely into the shell, which the animal does when inactive or threatened. ![]() The aperture is large and characteristically oblique, its margin in adults is whitish and reflected. The shell is variable in coloring and shade of color, but generally it has a reticulated pattern of dark brown, brownish-golden, or chestnut with yellow stripes, flecks, or streaks (characteristically interrupted brown colour bands). The adult bears a hard, thin calcareous shell 25–40 millimetres (1– 1 + 5⁄ 8 in) in diameter and 25–35 millimetres (1– 1 + 3⁄ 8 in) high, with four or five whorls. Sinistral form (exceptional) and dextral form (common) ![]() The snail is relished as a food item in some areas, but it is also widely regarded as a pest in gardens and in agriculture, especially in regions where it has been introduced accidentally, and where snails are not usually considered to be a menu item. It was classified under the name Helix aspersa for over two centuries, but the prevailing classification now places it in the genus Cornu. Of all terrestrial molluscs, this species may well be the most widely known. Cryptomphalus aspersus), known by the common name garden snail, is a species of land snail in the family Helicidae, which includes some of the most familiar land snails. Helix (Pomatia ) mazzulopsis Pilsbry, 1893Ĭornu aspersum (syn.Helix (Cryptomphalus ) betae Trechmann, 1938.
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