Pyramidula pusilla

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Pyramidula pusilla
Pyramidula pusilla

Pyramidula pusilla

Order : Lung snails (pulmonata)
Subordination : Land snails (Stylommatophora)
Superfamily : Pupilloidea
Family : Pyramid snails (Pyramidulidae)
Genre : Pyramidula
Type : Pyramidula pusilla
Scientific name
Pyramidula pusilla
Gittenberger & Bank , 1986

Pyramidula pusilla , also known as rock pyramid snail, is a species of snail in the family of pyramid snails (Pyramidulidae) from the suborder of land snails (Stylommatophora).


The small, right -hand wound case is pressed-top-shaped with very lightly shouldered turns rounded on the periphery and a deep seam. In the adult stage 4½ turns are formed. The case measures up to 2.95 mm in width and up to 2.25 mm in height, and is therefore significantly wider than it is high. The turns increase evenly, only the last loop drops slightly from the turn axis. The mouth is flattened, transversely shaped and is oblique to the axis of the winding. The edge of the mouth is thin, sharp and fragile. It is only slightly turned over in the navel area. The navel is open and deep and takes up about a quarter of the width of the case. In some populations this value can be up to a third.

The case is dark horn brown to reddish brown in color. In older animals, the color can already be faded and almost white. The surface shows very fine and closely spaced growth strips. This makes the case shine. The embryonic shell is almost smooth.

In the male tract of the genital apparatus, the spermatic duct penetrates apically into the epiphallus. A small sack-shaped appendix is ​​formed at the transition from the epiphallus to the penis. The penis is comparatively short. The penile retractor muscle attaches roughly in the middle of the epiphallus. In the female tract, the free fallopian tube is about twice as long as the vagina. The spermathec is small and oblong-elliptical in shape. It sits on a short stem. The protein gland is oblong-egg-shaped.

Similar species

Compared to Pyramidula pusilla, Pyramidula rupestris ismore highly conical and significantly higher than wide, or only very slightly wider than high. The whorls are more curved on the periphery. The hem of the mouth is turned over in the spindle area.

Distribution of Pyramidula pusilla in Europe (according to Welter-Schultes)

Geographical distribution and habitat

The rock pyramid snail has a huge distribution area that includes almost all of Western and Central Europe. In the northeast, the distribution area extends to the Baltic States, in the south to North Africa and in the southeast to eastern Turkey and the Middle East. There is an isolated occurrence in the Crimea.

In Germany it is mainly found in the southwest, the northernmost occurrences in Germany are the Hönnetal in the Sauerland , the Ith and Thuringia .

The rock pyramid snail lives on dry, exposed limestone rocks and walls. They hide in cracks and crevices, and crawl around on the surface in damp weather. It is bound to calcareous soils. In the Alps it rises up to 3000 m above sea level.

Way of life

Reproduction takes place in summer. The animals are ovoviviparous , i.e. H. the few (3 to 7, mostly 4 to 6) eggs are held back in the mantle cavity until the young hatch and individually crawl out of the mantle cavity. The young animals have a housing with a diameter of 0.8 mm and 1.5 turns.

The animals graze on the rock surfaces endolithic lichens . Due to their small size, the animals are often transported by birds. Anthropogenic spreading through cuttings and natural stones to which the animals are attached is also common.


According to Welter-Schultes, the name with this author is not available because Vallot's work was an internal examination paper and is therefore not available for scientific use.


The rock pyramid snail is in the red list of endangered animal species in the early warning level.


  • 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. 137/38.

Individual evidence

  1. Jürgen H. Jungbluth and Dietrich von Knorre: Trivial names of land and freshwater mollusks in Germany (Gastropoda et Bivalvia). Mollusca, 26 (1): 105-156, Dresden 2008 ISSN  1864-5127 , p. 121.
  2. Edmund Gittenberger, Ruud A. Bank: A new start in Pyramidula (Gastropoda Pulmonata: Pyramidulidae). Basteria, 60 (1/3): 71-78, Leiden 1996 PDF .
  3. a b Alexandru V. Grossu: Gastropoda Romaniae 2 Subclasa Pulmonata I Ordo Basommatophora II Ordo Stylommatophora Suprafamiliile: Succineacea, Cochlicopacea, Pupullacea. 443 pp., Bucharest 1987, pp. 337/38 (as Pyramidula rupestris ).
  4. ^ 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. 210)
  5. Sandra Kirchner, Josef Harl, Luise Kruckenhauser, Michael Duda, Helmut Sattmann, Elisabeth Haring: Phylogeography and systematics of Pyramidula (Pulmonata: Pyramidulidae) in the eastern Alps: still a taxonomic challenge. Journal of Molluscan Studies, 82: 110-121, 2016. doi : 10.1093 / mollus / eyv047
  6. Igor A. Balashov, Nina V. Gural-Sverlova: Terrestrial Molluscs of the genus Pyramidula (Pyramidulidae, Pulmonata, Gastropoda) in East Europe, Central Asia, and Adjacent Territories. Zoologicheskiĭ Zhurnal, 90 (12): 1423-1430, 2011 Research Gate
  7. Klaus Bogon: Landschnecken biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990 ISBN 3-89440-002-1 , p. 98/9 (described as Pyramidula rupestris )
  8. Hajo Kobialka: Contributions to the mollusc fauna of the Weserbergland: 2. Subalpine mollusc fauna from Ith with Pyramidula pusilla (Vallot 1801) and Deroceras rodnae Grossu and Lupu 1965 (Pyramidulidae and Agriolimacidae). Announcements of the German Malacoological Society, 61: 23-32, 1998 ISSN  0418-8861
  9. Ulrich Bößneck: The rock pyramid snail ( Pyramidula rupestris Draparnaud, 1801) in Thuringia. Publications of the Natural History Museum Erfurt, 12: 92-100, Erfurt 1993 (described as Pyramidula rupestris ).
  10. ^ AnimalBase
  11. ^ Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014 ISBN 978-3-494-01551-4 (p. 161)


  1. The name rock pyramid snail is also used for the closely related species Pyramidula rupestris .