Acroloxus
| Acroloxus | ||||||||||
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Pond limpet |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Acroloxus | ||||||||||
| Beck , 1837 |
Acroloxus is the eponymous genus of the family Acroloxidae , small, air-breathingpulmonate snails (Pulmonata) from the subordination of the water pulmonary snails (Basommatophora). Acroloxus (Greek: "crooked point") isnot closely relatedto the river limpets Ancylus fluviatilis .
features
The cases are small (less than 1 cm), cup-shaped and not very sculpted. Usually there are only more or less clearly visible growth strips. The shell is thin and translucent. The apex points back to the left. In the mantle cavity, the animals have a protuberance of the mantle that functions as a secondary gill. However, oxygen is also absorbed via the remaining surface of the soft body. The secondary gill and also the genital orifices are on the right side.
Habitat and occurrence
The species occur predominantly in Europe, also regionally in North America. Many occurrences appear to be limited in extent; only the pond limpet , widespread from Central to Eastern Europe, has a somewhat larger coherent distribution.
Depending on the species, the snails prefer to live in clear, stagnant or slowly flowing waters (lakes, ponds, ponds, subterranean waters up to source regions) on parts of plants, wood, stones, rocks or on other mollusc shells.
Systematics
The genus is currently divided into five types:
- Acroloxus coloradensis (Henderson, 1930); regional in North America (Quebec, Ontario, Colorado)
- Acroloxus improvisus Polinski, 1929; Lake Ohrid (especially at a slightly greater depth in the area of the shell zone)
- Acroloxus lacustris (Linnaeus, 1758), the European pond limpet ; Great Britain, Central and Parts of Eastern Europe, Southern Northern Europe; locally and occasionally in other areas
- Acroloxus macedonicus Hadžišce, 1959; Lake Ohrid (especially in the upper littoral zone)
- Acroloxus tetensi (Kušcer, 1832); Slovenia (caves and springs in the Ljubljanica catchment area); also possible in northern Italy
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