Narrow diaper snail

Narrow diaper snail
	Narrow diaper snail
Systematics
Subordination :	Land snails (Stylommatophora)
Superfamily :	Pupilloidea
Family :	Diaper snails (Vertiginidae)
Subfamily :	Vertigininae
Genre :	Vertigo
Type :	Narrow diaper snail
Scientific name
	Vertigo angustior
	Jeffreys , 1830

The narrow diaper snail ( Vertigo angustior ) is a type of snail from the family of the diaper snail (Vertiginidae), which belongs to the subordination of the terrestrial lung snail (Stylommatophora). At just under 2 millimeters, it is a very small shape with a left-handed housing; Due to its small size, the shape is included in the non-systematic group of "micromollusks".

features

The left-hand wound case has 4.5 to 5.35 turns (mean: 5) and measures 1.6 to 2.0 mm (mean: 1.8 mm) in height and 0.9 to 1.05 mm (mean: 1.8 mm) in height : 1 mm) in width (1.5 to 1.9 × 0.9 to 1.0 mm: Welter Schultes). It is elongated egg-shaped and becomes narrower again at the base. This gives it the typical spindle-shaped design of the housing. The mouth is relatively small. The mouth edge is bent and somewhat thickened. The mouth is slightly notched on the outside. The notch continues on the outside as a spiral notch. Inside the mouth there is a long, lamellar protrusion (upper palatal tooth) in the notch. A total of 5 to 6 teeth protrude into the mouth. Four teeth (parietal, angular, columellar and upper palatal) are always present. Often there is a lower palatal tooth, rarely a tuberculous basal tooth. The housing is brown, horn-colored to yellowish brown and has a fine streak of growth.

Similar species

The species is easy to distinguish from the left-wound diaper snail ( Vertigo pusilla ). The other types of Vertigo are right-handed. The case is also typically spindle-shaped, but significantly larger and has dense, regular growth stripes. In addition, vertigo pusilla has six to nine teeth in the mouth.

Geographical distribution and habitat

The narrow diaper snail occurs in almost all of Europe with mostly small, isolated populations. The species is absent in northern Scandinavia and the southern Mediterranean . In the east their distribution area extends to the southern Urals, in the southeast to the Caucasus and northern Iran.

The animals live in wet meadows, along small watercourses or in damp moss in wet dune hollows.

Reproduction

According to observations made in Poland, egg-laying began in May and ended at the end of September, depending on age and season. The animals laid eggs in the summer months for up to three years. An animal laid up to 111 eggs during one season. At the beginning, one egg was laid every day, and occasionally two eggs within 24 hours. Later in the season, the intervals between oviposition increased (5 to 15 days). The eggs are gelatinous and almost colorless. They are shaped like a flattened sphere; they are seldom flattened elliptical. The egg chamber is enclosed by three layers. The surface of the outer layer always has a granular structure. The diameter is 0.48 to 0.66 mm (mean: 0.59 mm). The eggs were mostly laid in the single-cell stage, occasionally the embryos in freshly laid eggs were also somewhat more developed. The development time is temperature dependent. At 23 ° the young hatch after 11 days, at 21 ° after 13 days and at 19 ° after 16 days. At the time of hatching, the young had already formed a housing with 1.2 to 1.3 coils. The young grew very quickly and by 40 to 55 days had already reached adult size. After that, only the bent-back mouth lip was enlarged a little and the mouth reinforcement formed. Depending on the location, 25 to over 50% of the young animals hatched in one year reach sexual maturity in the same year. At the beginning of October the animals generally stopped their activity and went into hibernation. They only became active again in late April or early May. The hibernation is documented in the housing by two or three lighter growth strips and / or damage in the periostracum . The animals can live to be over three years old. Most die at the end of the first or second egg laying season. The survey of the age structure of a population in mid-September 2007 showed: 53.3% had hatched this year, 28% had hatched a year ago, 11.3% had hatched two years ago and only 6.7% had hatched three years ago .

A high percentage of aphallic animals was observed in the populations. These animals can therefore not function as males, but only as females. Self-fertilization is also possible. In Poland the proportion of aphallic specimens was more or less constant 40% (Pokryszko), in Wales a relatively constant proportion of up to 80% aphallic specimens was observed in one population.

The animals feed on detritus, dead, but not woody plant parts and on microorganisms that grow on the dead plant parts.

Danger

The populations of the slim diaper snail are declining due to the destruction of their habitats. The species is on the "Red List" of endangered animals in Germany and is classified as endangered (risk category 3). This species is listed in Appendix II of the Habitats Directive and is therefore also protected at European level. According to Article 3, Paragraph 1 of this guideline, the member states must designate protected areas for the Natura 2000 network for habitats of this type and ensure the continued existence or, if necessary, the restoration of a favorable conservation status.

Taxonomy

The taxon was first described in 1830 by John Gwyn Jeffreys as Vertigo angustior . The slender diaper snail is placed by many processors in the sub-genus Vertilla of the genus Vertigo , z. T. Vertilla is also rated as an independent genus.

Kiss & Kopf (2010) list the following synonyms :

Pupa gothorum Westerlund, 1878
Vertigo hamata hero, 1837
Vertigo nana Michaud, 1831
Vertigo plicata A. Müller, 1838
Pupa producta Westerlund, 1878
Vertigo venetzii Charpentier & A. Férussac , 1837

supporting documents

literature

Klaus Bogon: Land snails biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990 ISBN 3-89440-002-1 (p. 108)
Rosina Fechter & Gerhard Falkner: Mollusks. 287 pp., Mosaik-Verlag, Munich 1990 (Steinbach's Nature Guide 10), ISBN 3-570-03414-3
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. 91)
Stanisław Myzyk: Contribution to the biology of ten vertiginid species. Folia Malacologica, 19 (2): 55-80, Warsaw 2011 doi : 10.2478 / v10125-011-0004-9 .
Stanisław Myzyk: Egg structure of some vertiginid species (Gastropoda: Pulmonata: Vertiginidae). Folia Malacologica, 13 (4): 169–175 Abstract, full text only with registration
Beata M. Pokryszko: The Vertiginidae of Poland (Gastropoda: Pulmonata: Pupilloidea) - a systematic monograph. Annales Zoologici, 43 (8): 133-257, Warsaw 1990.
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
Michael L. Zettler, Uwe Jueg, Holger Menzel-Harloff, Uwe Göllnitz, Siegfried Petrick, Eckhard Weber & Renate Seemann: The land and freshwater mollusks of Mecklenburg-Western Pomerania. 308 p., Obodriten-Druck, Schwerin 2006, ISBN 3-933781-52-3

On-line

Animal Base: Species summary for Vertigo angustior

Individual evidence

↑ ^a ^b ^c Yvonne Kiss, Thomas Kopf: Profiles on the Vertigo species (Gastropoda: Vertiginidae) of Appendix II of the Habitats Directive in South Tyrol (Italy). Gredleriana, 10: 163-186, Bolzano PDF (3.5 MB)
↑ JH Jungbluth, D. von Knorre (with the assistance of U. von Bössneck, K. Groh, E. Hackenberg, H. Kobialka, G. Körnig, H. Menzel-Harloff, H.-J. Niederhöfer, S. Petrick, K Schniebs, V. Wiese, W. Wimmer, ML Zettler): Red list of internal mollusks [snails (Gastropoda) and mussels (Bivalvia)] in Germany. Announcements of the German Malacoological Society, 81: 1-28, Frankfurt / M. 2009 (p. 23) PDF ( Memento of the original dated June 16, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (1.3 MB) @1@ 2

^ John Gwyn Jeffreys: A synopsis on the testaceous pneumonobranchous Mollusca of Great Britain. Transactions of the Linnean Society of London, 16 (2): 323-392, London Online at www.biodiversitylibrary.org (p. 361/2]

^ Jean (Johann) de Charpentier: Catalog des mollusques terrestres et fluviatiles de la Suisse; par. Formant la seconde partie de la Faune helvétique. 28 p., 1837 Online at www.biodiversitylibrary.org (p. 18)