Colorless gloss snail
| Colorless gloss snail | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Colorless gloss snail ( Oxychilus clarus ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Oxychilus clarus | ||||||||||||
| ( Hero , 1838) |
The colorless gloss snail ( Oxychilus clarus ) is a snail native to Central Europe - a species of the gloss snail (Oxychilidae) in the suborder of the land snail (Stylommatophora).
features
The right-hand wound, quite small housing is flattened-conical, it measures 4 to 4.5 mm in diameter (width) and 1.6 to 2 mm in height. In the adult stage, four to five coils are formed, which increase regularly. Each turn is about twice as wide as the previous turn. The thread is only slightly raised in the side view. The top of the whorls is very flat, so the seams are also very flat. The periphery is well rounded, as is the underside. The mouth is flattened elliptical in plan. The mouth edge is straight and sharpened. The navel is wide and slightly eccentric.
The skin is colorless to whitish and translucent. When fresh, the surface of the case shines. There are fine growth stripes and fine spiral lines.
In the hermaphroditic genital apparatus, the spermatic duct (vas deferens) is very shortly before it joins the epiphallus. The epiphallus is essentially loosely attached to the penis. At the point of entry of the spermatic duct into the epiphallus, the epiphallus is connected to the penis by a tissue covering. The penis is short and has a blind sac (caecum, usually called the flagellum in this group) at the apical end, to which the penis retractor muscle attaches apically. The epiphallus penetrates the penis laterally below the apical end of the penis (plus blind sac). The penis is surrounded at the lower end by a penis sheath, which is slightly different in length; it can cover up to about half of the proximal part of the penis. Only longitudinal folds are formed inside the penis. The longitudinal folds are straight or longitudinally corrugated and can be connected to one another with lateral extensions. In the female tract, the free fallopian tube (oviduct) is slightly shorter than the vagina. The perivaginal gland envelops the upper part of the vagina and the lower part of the free fallopian tube, as well as the lower part of the stem of the spermathec. The comparatively thin stalk of the spermathek is long and lies against the egg ladder (spermoviduct). The bladder is small and rounded. The penis and vagina open into a short atrium. The radula has 25 to 31 teeth per transverse row.
Similar species
The shape of the shell is reminiscent of the brown striped snail ( Perpolita hammonis ); But in the adult stage this has only three to three and a half turns. The mouth rim is greatly enlarged.
Geographical distribution and habitat
The deposits are isolated and spatially very small, for example in the Southern Pyrenees ( Aragon ), France (Hautes Alpes, Isère, Corsica), the Swiss Alps ( Saillon , Canton Wallis, Samnaun , Canton Graubünden), Austria (Vorarlberg, Lower Austria), Germany ( Mittenwald and S of Munich) and Northern Italy.
The animals live in the humus layer under stones, between roots, in crevices; under dead wood and on grassy slopes. They live on calcareous soils between 390 and 2500 m above sea level. In Corsica they were found in mixed forests between 600 and 1000 m above sea level on non-califerous soils.
Taxonomy
The taxon was first described by Friedrich Held as Helix clara in 1838 . The taxon is generally accepted and is mostly placed in the genus Oxychilus Fitzinger, 1833. Authors who prefer a sub-genus subdivision of the genus Oxychilus place them in the sub-genus Oxychilus (Ortizius) Forcart, 1957.
Danger
According to Vollrath Wiese, the species is now extinct or lost in Germany. the species is also very rare in the rest of the distribution area and with large gaps between the individual populations. The IUCN classifies the species as near threatened (potentially endangered).
Individual evidence
- ↑ 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.
- ↑ Lothar Forcart: taxonomic revision palaearctic Zonitinae. I. Archiv für Molluskenkunde, 86: (4/6): 101-136, Frankfurt / main 1957, p. 125.
- ↑ Edmund Gittenberger, HPMG Menkhorst, JGM Raven: New data on four European terrestrial gastropods. Basteria, 44: 11-16, 1980 PDF
- ^ Friedrich Held: Notes on the molluscs of Bavaria. (Continuation.). Isis 1837 (12): 902-919, Leipzig 1838.
- ↑ Oxychilus glaber (Rossmässler, 1835)
- ↑ MolluscaBase: Oxychilus clarus (Held, 1838)
- ↑ 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 (p. 380)
- ↑ a b Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014 ISBN 978-3-494-01551-4 (p. 184)
- ↑ Fauna Europaea: Oxychilus (Ortizius) clarus (Held, 1838)
- ^ 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. 169/70 (as Oxychilus (Ortizius) clarus )
- ↑ The IUCN List of Threatened Species: Oxychilus clarus