Forest cone

Forest cone
Forest cones ( Euconulus trochiformis ) (Original picture by Montagu 1803: Plate 11, Fig. 9)
Systematics
Subordination : Land snails (Stylommatophora) Superfamily : Trochomorphoid Family : Cones (Euconulidae) Subfamily : Euconulinae Genre : Euconulus Type : Forest cone
Scientific name
Euconulus trochiformis
( Montagu , 1803)

The forest cone ( Euconulus trochiformis ) is a species of snail in the family of cones (Euconulidae) from the suborder of land snails (Stylommatophora).

features

The right-hand winding case is conical with a moderately convex base. In its habitus, the housing therefore appears conical-spherical. The dimensions are: 2.8 to 3.5 mm in width and 2 to 2.5 mm in height. It has 5 whorls that increase moderately and evenly. The passages are strongly arched on the periphery and separated from each other by a deep seam. The outer line is almost straight. The mouth is at an angle to the coil axis. The mouth is asymmetrically crescent-shaped. The edge of the mouth is simple, straight and not thickened. Due to the tight winding, no navel can be seen.

The cases are honey brown and translucent. The top of the case is very shiny. There are faint spiral lines at the bottom. Here the surface is only matt-glossy.

The soft body of the animal is gray. Because the soft body shines through the shell, the housing looks light brown.

Similar species

The dark cone ( Euconulus praticola ) has the darkest casing, followed by the forest cone, which has a much lighter casing. The light cone ( Euconulus fulvus ) is very bright (and the brightest ). This is due to the color of the soft body. The dark cone ( Euconulus praticola ) has a blue-black to black soft body, the forest cone a light gray soft body, while the light cone also has a very light soft body.

The base of the dark cone is less flattened and more rounded compared to the two other cones, and the seam is deeper. In the case of the light cone, the mouth is approximately symmetrical, crescent-shaped, while the dark cone and the forest cone have a clearly asymmetrical crescent-shaped mouth. The dark cone and the forest cone inhabit more humid habitats than the light cone.

Geographical distribution and habitat

The distribution area is only very poorly known. Welter-Schultes indicates Europe including the British Isles and Scandinavia.

The species prefers old damp forests, where the animals live in the leaf and litter. The species seems to prefer more humid locations than the Helle Kegelchen. Occasionally both types appear sympatric . In Switzerland the species rises up to 2500 m above sea level. It generally lives there in very humid biotopes on the edge of semi-eutrophic Carex swamps and plains. It is often associated with the pond snail ( Vertigo antivertigo ).

Taxonomy

The taxon was established by Georges Montagu in 1803 . According to the current state of knowledge, it is likely that three Euconulus species occur in Central Europe , but through species delimitation, variability, ecological classification and z. Sometimes there is still no clarity about the nomenclature. The transfer of the taxon (called) trochiformis described from England to continental European forms is particularly controversial . The Fauna Europaea and the MolluscaBase treat trochiformis as valid names of this species. Only molecular genetic and more in-depth taxonomic-nomenclature investigations should bring new insights into whether the continental European form is really identical to the form described in England.

Danger

According to the IUCN Red List of Threatened Species , the species is not endangered. However, the occurrences known so far are very local. Only three occurrences are known from France. The species is more common in Switzerland, but even here the occurrences are very local. It is considered endangered in Austria and endangered in Switzerland, as well as in Lower Saxony, Rhineland-Palatinate and Bavaria. For Germany as a whole, the data situation is not sufficient to make statements about the existing situation.

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. ↑ ^{a b} George Montagu: Testacea Britannica, or natural history of British shells, marine, land, and fresh-water, including the most minute: systematically arranged and embellished with figures. Pp. I-XXXVII (= 1-37), pp. 1-606, White, London, 1803 Online at Biodiversity Heritage Library , p. 427
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. ^ ^{A b} 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)
4. ↑ AnimalBase: Euconulus trochiformis (Montagu, 1803)
5. ^ Gerhard Falkner, Theo EJ Ripken, Margrit Falkner: Mollusques continentaux de France. List of References and Bibliography. Patrimoines naturels, 52: 350 pp., Paris 2002 ISBN 2-85653-539-9 , pp. 120/21.
6. ↑ Fauna Europaea: Euconulus trochiformis (Montagu, 1803) (accessed June 18, 2018)
7. ↑ MolluscaBase: Euconulus trochiformis (Montagu, 1803)
8. ↑ The IUCN Red List of Threatened Species: Euconulus trochiformis
9. ^ Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014 ISBN 978-3-494-01551-4 (p. 171)