Systematics of Gastropoda: Clade Caenogastropoda: Hydrobiidae.Spring snails are a very diverse family of small to tiny snails inhabiting fresh or brackish water, also appearing on humid ground near the coast. Very few species also actually are found in the sea, on muddy ground among seaweed. It is estimated there are about 300 species in North and South Europe, about 1000 species worldwide, in Australia alone 280 species are mentioned. In Central Europe many spring snail species inhabiting ground water, caves or springs are limited to one single geographic finding site, which means a very large ecological threat to those species.
Systematics of Gastropoda: Clade Caenogastropoda: Hydrobiidae.
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Laver Spire Snail - Peringia ulvae (Pennant 1777).
Laver spire snail (Peringia
ulvae).
 Spring snail (Belgrandiella wawrai). Picture: © Alexander Mrkvicka, Vienna (mrkvicka.at). |
Belgrandiella aulaei Haase,
Weigand & Haseke
2000
Belgrandiella austriana (Radoman
1975)
Belgrandiella boetersi Reischütz
& Falkner 1998
Belgrandiella fuchsi (Boeters
1970)
Belgrandiella ganslmayri Haase
1993
Belgrandiella kreisslorum Reischütz
1997
Belgrandiella mimula Haase
1996
Belgrandiella multiformis Fischer
& Reischütz 1995
Belgrandiella parreyssii (L. Pfeiffer
1841)
Belgrandiella pelerei Haase
1994
Belgrandiella styriaca Stojaspal
1978
Belgrandiella wawrai Haase
1996
Source: Wolfgang Fischer: Checklist of Austrian Mollusca.
Among the spring snails of the Belgrandiella genus there is also the thermal spring snail Belgrandiella pareyssii, which shares the thermal springs of Bad Vöslau in Lower Austria with the thermal spring nerite (Theodoxus prevostianus) and the thermal spring pitch snail (Esperiana daudebartii).
 Another group of spring snails are the Sadleriana genus (this is Sadleriana schmidtii from Slovenia). Picture: © Alexander Mrkvicka, Vienna (mrkvicka.at). |
Spring snails (Sadleriana) from Slovenia and Croatia.
Fountain snails not only live in fountains. There are many cave-dwelling species among them, as are species living in the ground water. Some attention the snail Husmann's fountain snail received by being elected mollusc of the year 2009.
The snail with the scientific name Bythiospeum husmanni at the current state of knowledge exclusively is to be found in the ground water flow accompanying the river Ruhr in North Rhine-Westphalia. It is only able to survive in extremely clean and constantly cool ground water. Its appearance therefore also is valued as an indicator for the innocuousness of this area's ground water as a resource for drinking water. In the rear part of the snail's head two kidney shaped red spots are recognizable, those are the odontophores, where the muscles are attached, moving the rasp tongue (radula) armed with numerous rows of seven toothlets each.
Fountain snails are known from France, Germany, the Netherlands, Switzerland, Austria, Hungary, Slovenia and Northern Italy. There are 50 scientific names of fountain snails of this widely unresearched genus in Germany alone.
Research
group molluscs NRW:
Mollusc of the year 2009 - Husmanns Brunnenschnecke (Bythiospeum
husmanni BOETTGER 1963). (In
German)
Tierdoku.com:
Husmanns Brunnenschnecke. (In German)
NABU:
Bakterienweide im Grundwasserstrom - Husmanns
Brunnenschnecke. (In German)
Franz Brümmer, Gerhard Falkner,
Hans-Jörg Niederhöfer, Michael Schopper & Rainer Straub:
Brunnenschnecken aus Karstquellen. (In German)
New Zealand mud snail - Potamopyrgus antipodarum (Gray 1843)
 New Zealand mud snail (Potamopyrgus antipodarum). Picture: © Alexander Mrkvicka, Vienna (mrkvicka.at). |
The New Zealand mud snail, apart from the Lusitanian slug (Arion lusitanicus or vulgaris) and the wandering mussel (Dreissena polymorpha), may be one of the best known neozoa in Central Europe. Around 1850 it was introduced by ship from New Zealand to Great Britain, from where it has spread through almost all of Europe.
 Potamopyrgus antipodarum. Picture: © Alexander Mrkvicka, Vienna. |
Description: Potamopyrgus antipodarum has an erect conical shell with strong walls, a pointed apex and slightly rounded whorls. The shell mouth is pointedly oval, the shell navel (umbilicus) is closed. The shell is glossy, yellowish to reddish brown in colour. The relation between height and width is variable, by parasitic castration there may be more whorls, and as a consequence larger specimens.
Dimensions: H: 4 - 6 mm; W: 2 - 3 mm; N: 5½. (Abbreviations).
Habitat and Distribution: The New Zealand mud snail lives in brackish and fresh water, it tolerates a salinity of up to 1.7%. Potamopyrgus antipodarum is usually found in the surf zone of rivers, as well as in ditches, where it also serves as food source for fish.
Of the most native water snail groups the New Zealand mud snail is different in its high tolerance against eutrophic conditions. It also tolerates temperatures between 0 and 34 °C, periods of dryness of up to 24 hours, up to 50 days on a humid surface. It is able to pass the digestive system of birds and so be additionally distributed.
Partly, appearances in high numbers have been recorded, such as 100,000 specimens per square metre (in some places Potamopyrgus antipodarum takes 95% of the overall invertebrate biomass). This is ecologically problematic, as so the spring snail replaces not only other molluscs species, but also the fish species feeding on them.
Potamopyrgus antipodarum, to a large extent, reproduces parthenogenetically. While in the beginning it had been assumed exclusively so, in the meantime male specimens have been found, so sexual reproduction is possible.
 Picture: © Alexander Mrkvicka, Vienna. |
New Zealand mud snail (Potamopyrgus antipodarum) from the Timavo springs near Trieste, Italy.
 Pyrgula annulata from Lake Garda (Italy). Picture: © Alexander Mrkvicka, Vienna. |
Pyrgula annulata Linnaeus 1758
Description: Pyrgula annulata is a relative of spring snails. Its shell can be recognized by the conspicuous sharp keels running ring-like along the whorls, one along the periphery and one weaker keel below.
Dimensions: H: 4 - 10 mm; W: 2.5 - 4 mm.
Habitat and Distribution: The ringed spring snail (according to the approximate translation of the species' scientific name) can be found in Lakes between Northern Italy and Northern Albania. In Dalmatia, the species is also found in springs.
Francisco
Welter-Schultes:
Pyrgula annulata species homepage.