Quender snail
| Quender snail | ||||||||||||
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Quail snail ( Candidula unifasciata ) |
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| Scientific name | ||||||||||||
| Candidula unifasciata | ||||||||||||
| ( Poiret , 1801) |
The common snail ( Candidula unifasciata ) is a species of snail of the Geomitridae family from the order of the land snail (Stylommatophora).
features
The spherical, pressed-conical housing is 3 to 6 mm high and 5 to 9 mm wide (3.5 to 5 × 5.5 to 7 mm: Welter Schultes). It has five to six regularly increasing arched turns, each of which is separated from one another by a deep seam. They form a slight edge on the periphery.
The deep, moderately wide navel is slightly eccentric. It takes up about 1/5 to 1/7 of the width of the case. The last passage only lowers shortly before the mouth and only very slightly. The mouth is oblong and flattened at the top. In the lower part of the mouth there is a mostly strong, partly tooth-like lip, which, however, can be very flat or even absent in some specimens.
The solid-shell housing is whitish and opaque . The surface is fine and regularly ribbed. The drawing usually shows a dark brown spiral band just above the periphery, it can be interrupted or completely missing. Further, very pale bands or spots (rows) may be present below the periphery. The ribs on the last handle are a bit stronger.
The soft body is ash gray with a slightly darker neck and darker antennae. In the male genital tract, the spermatic duct (vas deferens) enters the epiphallus at a sharp angle. The flagellum is quite short. The epiphallus is four times as long as the penis. The penile retractor starts in the distal part of the epiphallus just before the transition to the penis. The penis is spindle-shaped internally. In the female tract, the free fallopian tube is moderately long. The arrow sack is quite large and starts at the atrium. There is only one love arrow . There are two glandulae mucosae, each with two to three branches. The stem of the spermathec is only moderately long, the bladder comes to lie about half the length of the egg ladder.
Similar species
The light heather snail ( Candidula gigaxii ) has a slightly larger shell and less well-arched whorls, a less developed seam. It is also usually more pressed or less conical. The shell of the spotted heather snail ( Candidula intersecta ) has coarser and somewhat more irregular ribs and is more clearly keeled on the periphery.
Geographical distribution and habitat
The range of the species is very scattered and stretches from France over Belgium, the Netherlands, Germany, Denmark, Switzerland, Poland, Czech Republic, Austria up to Hungary (here probably introduced). There are isolated occurrences on the island of Gotland, Slovakia, Italy and Croatia.
The species inhabits dry, warm, open or rocky, mostly south-exposed locations from the plains to the mountains. On the coast it is also found on dunes, inland also on dry stone walls, in gardens and vineyards. In the Swiss Alps it rises to 2400 m above sea level. According to Markus Pfenninger et al. (2007), the light heather snail from the south of France probably expanded to its present-day distribution area in Roman times.
Way of life
The animals live to be two to three years old. The (only) clutch consists of 22 to 56 whitish, slightly elliptical eggs with a diameter of 0.7 to 1.0 millimeters.
Taxonomy
The taxon was set up as Helix unifasciata from 1801 by the almost exclusively botanical scientist Jean Louis Marie Poiret . The species is now uniformly placed in the genus Candidula Kobelt, 1871. It is de facto the type species of this genus, since the formal type species of the genus, Glischrus (Helix) candidula Studer, 1820 is a younger synonym of Candidula unifasciata (Poiret, 1801). It is also the type species of the genus Xeroalbina Monterosato, 1892, a more recent synonym by Candidula Kobelt, 1871.
Synonyms are Helicella candidula Studer, 1820 and Helix iriana Pollonera 1885. Edmund Gittenberger (1993) divided the taxon into three subspecies: Candidula unifasciata unifasciata (the nominate subspecies), Candidula unifasciata rugosiuscula (Michaud, 1831) and Candidula unifasciata acuosmia (1882) . The fauna Europaea lists four subspecies in addition to the nominotypical subspecies:
- Candidula unifasciata rugosiuscula (Michaud, 1831), is characterized by a regular, dense and distinct rib. The taxon is described by Markus Pfenninger et al. (2007) treated as a separate species.
- Candidula unifasciata acosmia (Bourguignat, 1882) has coarse, more irregular ribs and a pronounced edge on the periphery
- Candidula unifasciata soosiana (H. Wagner, 1930), has coarse, more irregular ribs
- Candidula unifasciata vincae (De Stefani, 1883) (orig. Taxon Helix unifasciata forma Vincae ), with a slight keel on the periphery, the lower edge of the mouth flattened
The zoologist Francisco Welter-Schultes does not accept subspecies.
Danger
The whelk snail is classified as not endangered for its entire range. On the other hand, it is on the red list in Germany and is viewed as highly endangered, as is the case in Austria (Welter-Schultes).
supporting documents
literature
- Klaus Bogon: Land snails biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990, ISBN 3-89440-002-1 (p. 302/3).
- Rosina Fechter and Gerhard Falkner: molluscs. 287 pp., Mosaik-Verlag, Munich 1990 (Steinbach's Nature Guide 10), ISBN 3-570-03414-3 (p. 208).
- Edmund Gittenberger: On Trochoidea geyeri (Soos, 1926) and some conchologically similar taxa (Mollusca: Gastropoda Pulmonata: Hygromiidae). Zoologische Mededelingen Leiden, 67 (19): 303-320, Leiden 1993 PDF (p. 311/2).
- 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 (pp. 245/6).
- 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. 534).
On-line
Individual evidence
- ^ Wilhelm Kobelt: Fauna of the Nassau mollusks. Yearbooks of the Nassau Association for Natural History, 25/6: 1-305, Wiesbaden, 1871 (p. 118).
- ↑ a b Markus Pfenninger, Carsten Nowak, Frédéric Magnin: I ntraspecific range dynamics and niche evolution in Candidula land snail species. Biological Journal of the Linnean Society, 90: 303-317, 2007.
- ^ Ewald Frömming: Biology of the Central European Landgastropods. 404 S., Duncker & Humblot, Berlin 1954 (p. 245).
- ^ Jean Louis Marie Poiret: Coquilles fluviatiles et terrestres observées dans le département de l'Aisne et aux environs de Paris. Prodrome. Pp. I-XI, pp. 1-119, Paris, Barrois, & Soissons, Poiret, 1801. Online at www.biodiversitylibrary.org (p. 81).
- ↑ Fauna Europaea: Candidula unifasciata (Poiret 1801) .
- ↑ Carlo de Stefani: Minor Uschi Viventi nelle Alpi Apuane nel Monte Pisano e nell'Appennino adiacente. Bullettino della Società Malacologica Italiana, 9: 11-239, plate 9, Siena, Bargellini, 1883 Online at www.biodiversitylibrary.org (p. 113).
- ↑ Páll-Gergely, B. 2013. Candidula unifasciata. The IUCN Red List of Threatened Species 2013: e.T156810A5001213. doi : 10.2305 / IUCN.UK.2011-1.RLTS.T156810A5001213.en .
- ^ Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014, ISBN 978-3-494-01551-4 (p. 263).
