Helicodontidae
Strap screw ( Helicodonta obvoluta )
The belt snails ( Helicodontidae ) are a family from the subordination of terrestrial snails ( gastropod ). The family includes about 16 species.
Features
The housings are thick disc-shaped, flat, disc-shaped to flachkonisch. The case diameter of the adult animals extends to almost 20 mm. The umbilicus is narrow to moderately wide and always unlocked. The whorls are convex rounded or keeled. The aperture rim is folded more or less clear and may be gelippt or be drawn into teeth. In the case color prevail brown hues. The ornamentation is limited to more or less clearly pronounced growth lines. In some species sit on the surface of the housing long hair. The animals close their case in the summer of rest and / or during the winter break with a calcareous Epiphragma.
Occurrence, lifestyle and dissemination
The species of the family live under leaf litter and dead wood in forests, under stones, between rocks and screes. They live according to the type of fungi, detritus and fresh plants. The main application area is the eastern Mediterranean area, the southern Balkan Peninsula and Asia Minor. Some species are also common in the southern and western Alps. Only one species penetrates to Central Europe and the south of England before (probably relict occurrence).
System
The Helicodontidae family is treated by some authors still as a family of deciduous snails ( Hygromiidae ). In more recent work, however, it is considered as a separate family within the Helicoidea. The Fauna Europaea and Bouchet and Rocroi even make a subdivision of the belt screw into two subfamilies, Helicodontinae and Lindholmiolinae Schileyko, 1978.
- Belt snails ( Helicodontidae Kobelt, 1904) Helicodontinae Kobelt, 1904 Genus Atenia Gittenberger, 1968
- Genus Darderia Altaba, 2006
- Genus Drepanostoma Porro, 1836
- Genus Falkneria H. Nordsieck, 1989
- Genus Helicodonta Ferussac, 1821 Strap screw ( Helicodonta obvoluta )
- Genus Lindholmiola Hesse, 1931 Kissing island snail ( Lindholmiola lens )