Blunt pond snail
| Blunt pond snail | ||||||||||||
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Blunt pond snail ( Viviparus viviparus ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Viviparus viviparus | ||||||||||||
| ( Linnaeus , 1758) |
The blunt marsh snail , also river snail ( Viviparus viviparus ), is a freshwater snail from the family of marsh snail (order Architaenioglossa ).
features
The housing has 5.5 to 6 turns and is up to 4 cm high. The turns are rounded, but not stepped. They are separated from each other by a clear seam. The apex is blunt and the navel is narrow.
Way of life and distribution
V. viviparus lives in moderately flowing rivers and lakes. It prefers clear water and lives from green algae (5%), higher plants (10%) and mostly from detritus (85%). With the help of threads of mucus that are formed at the base of the gill, food particles and plankton can be filtered out of the water. Then the mucus threads are eaten together with the detritus.
The species occurs in western, central and eastern Europe. In Scandinavia it was found as far as southern Norway and southern Sweden.
Similar species
One can best distinguish the two very similar species V. viviparus and V. contectus ( pointed mud snail ) on the basis of the separation of the individual circumferences of the shell: V. viviparus has slimmer, non-stepped shell coils; in the case of V. contectus , the more bulbous whorls are distinctly stepped. The apex of V. contectus is pointed, while V. viviparus is blunt. In V. viviparus the umbilicus is significantly narrower, almost closed.
Breakdown
The blunt pond snail is often still divided into two subspecies in the literature:
- Viviparus viviparus viviparus (Linnaeus, 1758)
- Viviparus viviparus penthicus (Servain, 1884)
The subspecies V. v. penthicus is said to occur only in the Bille , a small tributary of the Alster near Hamburg and in the Oder near Frankfurt / Oder . According to Glöer and Zettler (2005) it is probably just a miserable form of Viviparus viviparus .
Saprobic index
The saprobic index for this species is 2.0.
literature
- Peter Glöer: The animal world of Germany. Mollusca I Freshwater gastropods of Northern and Central Europe Key to identification, way of life, distribution. 2. rework. Ed., 327 pages, ConchBooks, Hackenheim 2002 ISBN 3-925919-60-0
- Peter Glöer and Michael L. Zettler: Annotated list of species of freshwater mollusks in Germany. Malakologische Abhandlungen, 23: 3-36, Dresden 2005 ISSN 0070-7260
Web links
- European Viviparidae - Viviparus viviparus
- Viviparus viviparus in the Red List of Threatened Species of the IUCN 2013.2. Posted by: Van Damme, D., Seddon, M. & Kebapçı, U., 2012. Accessed February 14, 2014.
Individual evidence
- ↑ Meyer, Detlef .: Macroscopic biological field methods for assessing the water quality of rivers: with lists of species for beginning and experienced investigators and detailed descriptions and images of the indicator organisms . 4th, unchanged. BUND, Hannover 1990, ISBN 3-9800871-4-X .