Three-tailed rock snail
| Three-tailed rock snail | ||||||||||||
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Three-tailed rock snail ( Helicigona trizona ) |
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| Scientific name | ||||||||||||
| Helicigona trizona | ||||||||||||
| ( Roßäßler , 1834) |
The three-tailed rock snail ( Helicigona trizona ) is a terrestrial snail species from the family of snails (Helicidae).
features
The housing is flattened to almost flat. It measures 13 to 18 × 25 to 32 mm. The turns increase only slowly; up to the adult stage about 4.5 to 5 turns are applied. In the cross-section, the turns are flattened at the top and rounded at the sides and at the bottom. The last turn drops significantly from the turn level and also rounds off on the upper side. The basic color is gray to yellowish-white with three brown spiral bands. The width of the bands increases slightly from the upper to the lower band. The middle band is clearly stronger and darker in color than the upper and lower bands. The periostracum is slightly green in color near the umbilicus and the edge of the mouth . The outside only shows clear growth stripes and very fine and indistinct spiral stripes. The mouth is rounded and is inclined to the winding axis (approx. 45 °). The whitish mouth edge is only slightly thickened and exposed on the inner side. The navel is comparatively narrow. The animal's body is light brown.
Geographical occurrence, habitat and way of life
The species occurs on the central Balkan Peninsula (Serbia, Bulgaria and south-western Romania). H. rumelica (Rossmässler, 1838), considered by many authors as a subspecies of H. trizona , is now recognized as an independent species. This reduces the occurrence to the above areas. It lives in moderately humid habitats up to 1700 m above sea level (Bulgaria). Almost nothing is known about the way of life.
Systematics
In the past, some taxa, which are now regarded as independent species, were placed as subspecies of Helicigona trizona , such as B. Helicigona rumelica (Rossmässler, 1838) and Helicigona haberhaueri (Sturany, 1897).
swell
Individual evidence
literature
- Rosina Fechter and Gerhard Falkner: molluscs. 287 pp., Mosaik-Verlag, Munich 1990 (Steinbach's Nature Guide 10) ISBN 3-570-03414-3
