Common crystal snail
| Common crystal snail | ||||||||||||
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Common crystal snail ( Vitrea crystallina ) |
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| Scientific name | ||||||||||||
| Vitrea crystallina | ||||||||||||
| ( OV Müller , 1774) |
The common crystal snail ( Vitrea crystallina ) is a snail native to Central Europe - a species of crystal snails (Pristilomatidae) in the suborder of land snails (Stylommatophora).
features
The right -hand winding , quite small case is flattened-conical with 4½ to 5 moderately curved and regularly increasing turns. It has a diameter (width) of 3 to 4 mm and a height of 1.4 to 2.1 mm. The thread is hardly raised in the side view. The turns are slightly curved on the top, the seam is shallow. The periphery is well rounded, as is the underside. When viewed directly from above, the mouth is crescent-shaped. The last turn has about one and a half to two times the diameter of the previous mouth. Apart from the rule, it does not expand towards the mouth. In adult specimens, the edge of the mouth is thickened by a weak, whitish lip set back from the edge of the mouth. The funnel-shaped and narrow umbilicus is slightly eccentric in the last turn. At first it is very narrow and only widens with the last turn.
The shell is transparent and colorless. occasionally also slightly greenish. The surface shows very fine, but irregular stripes. It is somewhat clear in the area of the seam, but can only be seen with a magnifying glass. The surface of the case is high-gloss, but dead cases quickly turn milky-white.
The back and the feelers of the soft body are colored gray, the sides become lighter towards the sole. The sole itself is whitish. On the navel side the body is dotted yellow; it shines through the housing.
In the hermaphroditic genitalia, the short sperm duct (vas deferens) opens apically into the long penis. There is no epiphallus. The penile retractor muscle also attaches apically to the penis. The spermathec is strongly regressed and only a small worm-shaped appendix. A free fallopian tube (oviduct) is very short. The vagina, on the other hand, is very long and the upper part is surrounded by the perivaginal gland. The vagina is thickly swollen in this area. The penis and vagina open into a short atrium.
Similar species
The shell is on average smaller than that of the ungrounded crystal snail ( Vitrea diaphana ), and larger than that of the wide-beaked crystal snail ( Vitrea contracta ), which is also more closely coiled. The umbilicus of the common crystal snail is narrower than that in the shell of Vitrea botterii and the wide-barked crystal snail.
Geographical distribution and habitat
The distribution area extends over Western, Central and Eastern Europe. In Norway it reaches up to 65 ° N, in Finland just to the south coast. In the east it extends in a wedge shape to Russia to the Urals. However, the species is absent on the Iberian Peninsula, in central and southern Italy and on the Balkan Peninsula. But it still occurs in Romania. Presumably it was anthropogenically transported to Iceland. In Switzerland it occurs up to 2300 m above sea level.
The animals live in the leaf litter and humus layer under stones in damp forests, in moss and in floodplain and swamp forests. It also occurs in damp meadows, spring areas and swamps.
Taxonomy
The taxon was first described by Otto Friedrich Müller in 1774 as Helix crystallina . The taxon is generally recognized and there is currently little discussion about whether it belongs to the species. In older systematics, the genus Vitrea is divided into sub-genera. In this sub-genus it is placed under the sub-genus Vitrea (Crystallus) Lowe, 1855. Grossu, however, places them in the nominate subgenus Vitrea (Vitrea) Fitzinger, 1833.
Danger
According to Vollrath Wiese, the species is common in Germany and not endangered. The IUCN also classifies the species as harmless. According to Welter-Schultes, it is the most common species in the genus Vitrea Fitzinger, 1833.
Individual evidence
- ↑ a b c d Francisco W. Welter-Schultes: European non-marine molluscs, a guide for species identification = identification book for European land and freshwater mollusks. A1-A3 S., 679 S., Q1-Q78 S., Göttingen, Planet Poster Ed., 2012 ISBN 3-933922-75-5 , ISBN 978-3-933922-75-5 (S. 360)
- ↑ a b Vitrea crystallina ( OV Müller, 1774)
- ↑ Jürgen H. Jungbluth, Dietrich von Knorre: Trivial names of land and fresh water mollusks in Germany (Gastropoda et Bivalvia). Mollusca, 26 (1): 105-156, Dresden 2008 ISSN 1864-5127 , p. 122.
- ↑ Otto Friedrich Müller: Vermivm terrestrium et fluviatilium, seu animalium infusoriorum, helminthicorum, et testaceorum, non marinorum, succincta historia. Volume alterum. S. I-XXVI, 1-214, Heineck & Faber, Havniae / Copenhagen & Lipsiae / Leipzig, 1774 Online at www.biodiversitylibrary.org (p. 23).
- ↑ Klaus Bogon: Landschnecken biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990, ISBN 3-89440-002-1 , p. 188/89.
- ^ Rosina Fechter, Gerhard Falkner: Molluscs. Mosaik-Verlag, Munich 1990 (Steinbach's Nature Guide 10), 287 pages, ISBN 3-570-03414-3 , page 174
- ↑ MolluscaBase: Vitrea crystallina ( OV Müller, 1774)
- ↑ Fauna Europaea: Vitrea crystallina ( OV Müller, 1774)
- ↑ a b Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014, ISBN 978-3-494-01551-4 (p. 193)
- ^ MP Kerney, RAD Cameron, Jürgen H. Jungbluth: Die Landschnecken Northern and Central Europe . Parey-Verlag, Hamburg and Berlin 1983, 384 pp., ISBN 3-490-17918-8 , pp. 162/63
- ^ Alexandru V. Grossu: Gastropoda Romaniae 4 Ordo Stylommatophora Suprafam: Arionacea, Zonitacea, Ariophantacea şi Helicacea. 564 S., Bucharest 1983, pp. 102-104.
- ↑ The IUCN List of Threatened Species: Vitrea crystallina