Large gloss snail
| Large gloss snail | ||||||||||||
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Great gloss snail ( Oxychilus draparnaudi ) |
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| Scientific name | ||||||||||||
| Oxychilus draparnaudi | ||||||||||||
| ( Beck , 1837) |
The great gloss snail ( Oxychilus draparnaudi ) is a land snail from the family of the gloss snail (Oxychilidae); this family belongs to the subordination of land snails (Stylommatophora).
features
The right-hand wound housing measures about 7 to 14 mm in diameter and 4.5 to 6 mm in height in the adult animals. It is flat-conical, the apex is only slightly raised in the side view. The height of the thread can vary slightly. It has 5.5 to 6 turns that increase evenly except for the last turn. The last turn then increases a little more and the diameter of the last turn is more than twice as large as the penultimate turn. Often the last turn is also slightly lowered compared to the turn axis of the first turns. The mouth is transversely elliptical in plan, apart from the section through the previous turn. The mouth surface is slightly inclined to the coil axis. The mouth edge is straight and sharpened. The navel is moderately deep and wide.
The skin is yellow-brown, dark brown to red-brown and translucent. The surface shows weak growth stripes, which become a bit rougher, especially towards the seam, or make a wrinkled impression. Otherwise, the case is smooth and glossy.
The body of the animal is colored blue-gray or dark blue. As a result, the otherwise quite light case also appears very dark. The antennae and top of the body are often a little darker, the coat is gray. When touched or injured, a slight odor of garlic is noticeable. In the male tract of the hermaphroditic genital apparatus, the spermatic duct (vas deferens) is moderately long. It penetrates the epiphallus apically. This initially swells and then becomes thinner again as it progresses. The length in relation to the penis length varies from about half as long to about 1: 1. If the epiphallus is short, it is once bent into a U-shape, it is very long, even bent twice into a U-shape. In the area of the penis sheath, the epiphallus is connected to the penis by tissue shortly after the entry of the spermatic duct. The epiphallus enters the penis in front of the apex. The penis is extended apically by a short blind sac (caecum) to which the penile retractor muscle attaches. The penis is twice as long as the epiphallus to about the same length. The proximal part is separated from the distal part by a constriction. The two sections are connected by a thin "bottle neck". Longitudinal folds that are straight or slightly wavy are formed in the interior of the penis. In the upper third, the folds dissolve into a series of papillae. In the lower third, the penis is surrounded by a tissue cover (penis cover). In the female part, the free fallopian tube (oviduct) is very short and the vagina is very long. The perivaginal gland surrounds the upper part of the vagina and the basal part of the free fallopian tube, as well as the base of the stem of the spermathec. The stem is moderately long and thin. The bladder is round to ellipsoid and reaches the upper egg duct (spermoviduct). The penis and vagina open into a very short atrium.
Similar species
The last turn of the cellar gloss snail ( Oxychilus cellarius ) is somewhat narrower than that of the large gloss snail. The case is also a bit smaller on average. The garlic snail ( Oxychilus alliarius ) is significantly smaller and has a more raised thread, but also fewer turns. In the similarly large or even larger Mortillet's gloss snail ( Oxychilus mortilleti ), the umbilicus is slightly smaller and the mouth is flattened significantly more elliptically when viewed directly.
Geographical distribution and habitat
The species was originally only native to western and southwestern Europe as far as southwestern Germany. However, it has now been carried off across Central Europe. In Scandinavia it is only found in gardens and greenhouses. It is also found in other temperate regions of the world through anthropogenic displacement. In Switzerland it has already been found at 2,000 m above sea level, but it is very rare above 1,000 m.
The species originally lives in damp and protected locations in deciduous forests under leaves and between rocks. It now occurs in Central Europe (introduced) mainly in cultivated land, in gardens, parks, greenhouses, compost heaps, along roadsides and dumping areas for green material. in front.
Reproduction and way of life
The animals become sexually mature after eight or nine months and mate in early summer. The egg-laying begins in July and continues into autumn. The individual clutches contain 3 to 10, up to a maximum of 18 eggs, which are whitish-cloudy. The diameter of the eggs is 1.4 to 1.7 mm. A total of around 70 eggs are produced per animal. The development time depends on the temperature and takes about 30 to 40 days. The young hatch as finished little animals. At this point the housing has 1¼ turns. They can reach an age of around two years.
The great gloss snail lives predatory, mainly on other, smaller snails, but also on fresh and withered parts of plants. Especially young specimens of banded snails TYPES ( Cepaea ) to about 10 mm in size, and young slugs are the main prey. The housings are completely eroded, the housings remain completely intact. In the case of slugs, too, the lime flakes are neatly gnawed off. This means that the species does not meet its lime requirement by gnawing the shells of its prey, but exclusively through animal food. Francisco Welter-Schultes writes that they even eat cat and dog food.
In New Zealand, the predatory great gloss snail is a serious threat to native species. There she hunts the z. The native species Charopa coma (Gray), Chaureopa roscoei Climo, Flammocharopa costulata (Hutton), Flammulina cornea (Hutton), Cavellia buccinella (Reeve), Allodiscus dimorphus (Pfeiffer) and Laoma mariae (Gray) are already very rare . In some localities only introduced species were left, the native species had already disappeared.
Taxonomy
The taxon was first introduced to science in 1837 by Henrik Henriksen Beck under the name Helix (Helicella) Draparnaldi . However, he gave no description, only a reference to Figures 23 to 25 on Plate 8 in Draparnaud and to a figure in Rossmässler. The name was changed to draparnaudi by Opinion 336 of the Commission for the International Nomenclature . The taxon is generally recognized and is now part of the genus Oxychilus Fitzinger, 1833.
Some authors divide the genus Oxychilus into several sub-genera. In this classification, the great gloss snail is assigned to the nominate subgenus Oxychilus (Oxychilus) Fitzinger, 1833. The Fauna Europaea has 13 synonyms .
Danger
According to Vollrath Wiese, the population of the species in Germany is not endangered. The IUCN also rates the species as harmless across its entire range. But it is considered endangered in Albania.
literature
- Klaus Bogon: Land snails biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990, ISBN 3-89440-002-1 , p. 206/07.
- Rosina Fechter and Gerhard Falkner: molluscs. 287 p., Mosaik-Verlag, Munich 1990 (Steinbach's Nature Guide 10) ISBN 3-570-03414-3 , p. 180.
- Michael P. Kerney, RAD Cameron & Jürgen H. Jungbluth: The land snails of Northern and Central Europe. 384 pp., Paul Parey, Hamburg & Berlin 1983, ISBN 3-490-17918-8 , p. 170.
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.
- ^ Folco Giusti, Giuseppe Manganelli: How to distinguish Oxychilus cellarius (Müller, 1774) easily from Oxychilus draparnaudi (Beck, 1837) (Gastropoda, Stylommatophora, Zonitidae). Basteria, 61: 43-56, 1997 PDF
- ^ Adolf Riedel: Revision of the zonitides of Poland (Gastropoda). Annales Zoologici, 16 (23): 362-464, Posen 1957 PDF , pp. 410-414.
- ↑ a b c 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. 382)
- ^ Ewald Frömming: Biology of the Central European Landgastropods. 404 S., Duncker & Humblot, Berlin, 1954, pp. 89-97.
- ↑ a b Karin Mahlfeld: Impact of Introduced gastropods on molluscan communities, northern North Iceland. Wellington, 2000 PDF
- ^ Henrik Henriksen Beck: Index molluscorum praesentis aevi musei principis augustissimi Christiani Frederici. 124 p., Hafniae / Copenhagen, 1837 Online at Biodiversity Heritage Library .
- ↑ AnimalBase: Oxychilus draparnaudi (Beck, 1837)
- ↑ a b Fauna Europaea: Oxychilus (Oxychilus) draparnaudi (H. Beck, 1837)
- ↑ Oxychilus draparnaudi (H. Beck, 1837)
- ↑ a b Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014, ISBN 978-3-494-01551-4 (p. 186)
- ↑ The IUCN Red List of Threatened Species: Oxychilus draparnaudi