Light cone

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Light cone
Light cone (Euconulus fulvus)

Light cone ( Euconulus fulvus )

Systematics
Subordination : Land snails (Stylommatophora)
Superfamily : Trochomorphoid
Family : Cones (Euconulidae)
Subfamily : Euconulinae
Genre : Euconulus
Type : Light cone
Scientific name
Euconulus fulves
( OV Müller , 1774)
Eoconulus fulvus (from Taylor)

The light cone ( Euconulus fulvus ) is a species of snail in the family of the cone (Euconulidae) from the suborder of the land snail (Stylommatophora).

features

The right-hand wound housing is pressed-conical, the overall habit is slightly spherical with a flattened base. It measures 2.8 to 3.5 mm in width and 2.0 to 2.5 mm in height, the width-height index is 1.2 to 1.4, it is significantly wider than it is high. The housing has 5 to 6 evenly growing and tightly wound passages with weak keelings on the periphery. The last passage is only slightly keeled on the periphery. The seams are comparatively flat. The outer line is almost straight. Due to the very tight winding, the navel is barely or not at all recognizable. The mouth is inclined to the winding axis and is symmetrical crescent-shaped or crescent-shaped. The edge of the mouth is straight, thin and very fragile.

The cases are yellowish brown and translucent. The surface is rather silky-shiny on the upper side and covered with fine strips of growth. The underside is smooth and has hardly any spiral stripes.

In the genital apparatus, the spermatic duct enters the epiphallus apically, which is marked by a thickening and merges into the long penis. A large, blind sack-like appendix starts around the middle of the penis. The penile retractor is positioned approximately in the middle of the epiphallus. In the female tract, the free fallopian tube is very long, the lower part is glandular. The reservoir of the spermatheque is elliptical and moderately large. The stem of the spermatheque is comparatively very short and the reservoir still comes to lie below the egg ladder. The vagina is significantly shorter than the free fallopian tube, and the atrium is almost as long. The soft body is only slightly light brown or light gray in color. The foot is narrow and the tentacles relatively long.

Similar species

The dark cone ( Euconulus praticola ) has a blue-black to black soft body and a dark-honey-colored to red-brown housing. Since the housing is translucent, the housing also appears very dark in the living animal, while in the light cone it appears very light due to the light soft body. In the case of the light cone, the mouth is approximately symmetrical, crescent-shaped, while the dark cone has a clearly asymmetrical crescent-shaped mouth. The forest cone ( Euconulus trochiformis ) also has an asymmetrical crescent-shaped mouth.

Geographical distribution and habitat

The light cone has a Holarctic distribution. In Europe it occurs from northern Scandinavia to southern Spain and Sicily. the species is also known from North Africa. In the east the distribution area extends far to Siberia, in the southeast to the Middle East.

In Switzerland it rises up to 2900 m above sea level, but is already very rare above 2400 m. In Bulgaria it was found up to 1500 m above sea level.

The animals are found in the litter of coniferous and deciduous forests (especially the low mountain ranges and also the high mountains), on meadows and in swamps, mostly in very moist and rather cool locations. They live under and in damp leaves, rotten bark, under stones and especially on dead wood. The species is rock-indifferent and tolerates soils that are poor in lime.

Reproduction

According to older observations from the south of France, 20 to 30 eggs are laid under leaves from April to May. The young hatch after about 2 weeks.

Taxonomy

The taxon was introduced into scientific literature in 1774 by Otto Friedrich Müller as Helix fulvus . It is the type species of the genus Euconulus Reinhardt, established in 1883 by Pilsbry in Pilsbry & Ferriss (1910). The taxon is widely recognized.

According to the current state of knowledge, it is likely that three Euconulus species occur in Central Europe , but via species delimitation, variability, ecology and z. In some cases, there is still no clarity or agreement on the nomenclature either. Molecular genetic and more in-depth taxonomic-nomenclature investigations should bring new knowledge here.

Danger

The species is not endangered in Germany. In Switzerland, it is the most common land snail, alongside the spotted snail ( Arianta arbustorum ) and the spotted bowl snail ( Discus rotundatus ).

literature

  • Klaus Bogon: Land snails biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990 ISBN 3-89440-002-1 , p. 248
  • 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. 201.

Individual evidence

  1. ^ John William Taylor: Monograph of the land and freshwater Mollusca of the British Isles. Pts. 1-24. Leeds, 1894-1921.
  2. ↑ 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. 122.
  3. ^ Alexandru V. Grossu: Gastropoda Romaniae 4 Ordo Stylommatophora Suprafam: Arionacea, Zonitacea, Ariophantacea şi Helicacea. 564 pp., Bucharest 1983, pp. 401/02.
  4. ↑ J.-B. Gassies: Tableau méthodique et descriptif des mollusques terrestres et d'eau douce de l'Agenais. Pp. 1–209, Baillière Paris & Agen, 1849 Online at Biodiversity Heritage Library , p. 75
  5. ↑ Otto Friedrich Müller: Vermivm terrestrium et fluviatilium, seu animalium infusoriorum, helminthicorum, et testaceorum, non marinorum, succincta historia. Volume alterum. Pp. 1-214, Heineck & Faber, Havniae / Copenhagen & Lipsiae / Leipzig, 1774 [online at Biodiversity Heritage Library].
  6. ↑ AnimalBase: Euconulus fulvus (Müller, 1774)
  7. ↑ Fauna Europaea: Euconulus (Euconulus) fulvus (OF Muller, 1774) (accessed June 18, 2018)
  8. ↑ MolluscaBase: Euconulus fulvus (Müller, 1774)
  9. ↑ Tomasz Umiński & Urszula Focht: Population dynamics of some land gastropods in a forest habitat in Poland. Malacologia, 18: 181-184, 1979 Online at www.biodiversitylibrary.org .
  10. ^ Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014 ISBN 978-3-494-01551-4 (p. 169)
  11. ^ 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. 209)