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Viviparus viviparus viviparus - (LINNAEUS 1758) – common river snail
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Found at the driftline of the Ems river in Lower Saxony, April 2006
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Range, Habitat: The common river snail is found in Central and Eastern Europe as far as the Ural Mountains, in temperate and warm-temperate climates: In Skandinavia, very rarely: in the east of Southern Norway (two locations), Sweden (eastern regions of Central Sweden: Småland to Gästrikland provinces as well as further isolated locations), Denmark (one location in the Nørre Aa close by Randers). Commonly found in Estonia, Latvia, Lithuania (very common), Poland, the Netherlands (see Web Links: Atlasproject Nederlandse Mollusken) and Belgium. Otherwise, partially in limited areas, found in: Portugal (?), Great Britain and Ireland (see Web Links: National Biodiversity Network), France (e.g. Central Pyrenees; Bassin Artois-Picardie; canal d´Ille-de-Rance), Luxemburg (Moselle river), Northern Italy (Veneto, Mantova), the Czech Republic (e.g. Elbe river, Ohre river, North-Western Bohemia), Slovakia, Slovenia, Croatia, Bosnia-Herzegowina, Jugoslavia (e.g. in the Tiza river), Makedonia, Albania (e.g. Lake Ohrid), Greece (e.g. on Síros island), Bulgaria, Romania, Moldavia, Turkey Durusu Gölü, lakes by Samsun, Gala Gölü), Ukraine (e.g. in rivers and large lakes of the Pripjet swamps; Lake Babje, Desna river), Russia (e.g. in the river Don by Rostov; Western Siberia, e.g. in the Zivorodka/Novosibirsk). No findings in Finland, Switzerland, Austria or Hungary. In Germany the species has been known since 1912; it is common in the lowlands, especially in the hilly country of Northern Germany. Also in the Rhine Valley and in the lower reaches of the Main river. It is usually not found in the low mountain ranges and not at all in the upper reaches of the Danube and in Lake Constance. In nature, river snails are found in moderately moving water in larger brooks and rivers, but also in canals, more rarely in lakes. They do not only live on mucky or sandy substrate, but also (in habitats with stronger currents) on pebbly-stony ground. Habitats where Viviparus v.v. is found:
Water parameters: Lives in Central Europe in water bodies with temperatures varying seasonally between 3 and 26 °C. The species tolerates a pH from 6.8 to 8.6 with a general hardness of 0.82 to 5.2 °d according to literature. The common river snails tolerates a salinity of up to 3‰. Eutrophic waters are tolerated as long as the oxygen content is sufficient all year round. Reproduction: Like all Viviparidae, the common river snail is dioecious and ovoviviparous, i.e. it releases live young snails. In nature the animals, especially the females, can be observed to migrate in spring from deeper zones to the warmer shallow water zones of their habitat. In summer they can be found in high numbers in some places there. They mate during their entire period of activity between March and November. In the mild winters of Southern England, no significant reproductive pause could be observed. When mating, the male crawls to the right shell side of the female and inserts its penis widely projecting from the right tentacle into the female's vagina. Depending on the female's size in its uterus around 10 to 24 (max. 80) egg capsules of different stages will develop parallely. Females with embryos can be found at all times in nature, i.e. also in winter, whereas in this case they only have one tenth of the number of embryos they carry in summer. During hibernation the young snails keep developing, although at a slower speed, so that even in winter some young snails are released, few and far between, though. In nature, the most offspring are individually born in summer, especially between June and August. Then the young snails already have a shell diameter of 5 to 10 mm. In contrast to the their frontal mantle rim is smooth or has tiniest bulges at best. In accordance with that their shells are smooth or have only a few tiny bristles. Life span: In nature, these snails get 4 to 10 years old. Food: Like all Viviparidae the common river snail in nature feeds on algae growth, they take up detritus and bacteria when eating muck, and especially in summer they eat a considerable amount of plancton. They do not eat live higher plants. Examinations of their intestinal content resulted in about 5% green algae, 10% higher plants and 85% detritus. The plancton is filtered from the breathing water streaming through a ultra-fine net of slimy fibres (netting only 9 to 11 nm) at the gill basis. The clumped food particles are formed to a food pellet by a ciliate epithel and then transported to the outside in a groove at the right side of the head. From time to time the snail turns its head in order to eat those concentrated plancton pellets. Behavior: Adult river snails almost always stay on the ground. The short thick foot is assumed to be an adaptation against sinking into the soft mud. Young snails are a lot more mobile and frequently climb on aquatic plants. River snails hibernate (from October/November to March/April) dug into the bottom muck. During this time they do not eat anything and live on their reserves. When the winter is very long, a large part of the population might not wake up from hibernation. These snails also become inactive when there is a lack of food and dig themselves in. The additional "annual ring" that forms in this case might lead to overestimating the snail's actual age. Keeping and socialization in the aquarium: Probably mostly comparable to that of the Danube river snail (Viviparus acerosus). Parasites: As other aquatic snails, our native Viviparidae are an intermediate host for trematodes (liver flukes). The cercarias' (one of the fluke's larval stadiums) proper final hosts are water fowls, fish or amphibians. Most cercarias get into their final host by getting eaten together with the snail. Once there they penetrate the intestinal wall and infest the inner organs. As fail host often cows and sheep eating vegetation at the waterside, thus also swallowing snails, get infected. Additional information: Young snails that preferrably sit in the shallow water zones are a favorite food for ducks, e.g. mallards. Adult Viviparidae are also eaten by muskrats, Norway rats and otters. The common river snail is generally listed as critically endangered on the Red List Germany. In Poland it is listed as rare, in the Czech Republic as vulnerable. Reasons for endangerment are presumably hydrologic engineering projects and a generally bad water quality. In a natural Polish water body fertile hybrids of Vivparus viviparus viviparus and the pointy river snail (Viviparus contectus) have been detected by enzyme-electrophoretic analysis. These snails showed intermediary characteristics as a whole, but grow significantly larger (up to 55 mm long and 42 mm wide). As both parent species usually prefer different habitats, these hybrids are extremely rare. The river snails offered as "pond snails" in pet shops and hardware stores are usually taken from the wild in Eastern Europe, mostly Hungary or Poland. They seldomly belong to Viviparus viviparus described on this page, but rather the related species Viviparus acerosus and Viviparus contectus. Maybe Viviparus viviparus has been brought to Georgia/USA in the 1970s. As this species cannot be differentiated conchologically from the species native there, Viviparus georgianus, the respective findings are still disputed.
Superfamily: Ampullarioidea (GRAY 1824) Family: Viviparidae (GRAY 1847) As one recent subspecies of the common river snail in Europe Viviparus viviparus penthicus (SERVAIN 1884) has been described in literature: GLÖER & ZETTLER (2005) have found after closer examination that this subspecies is probably just a stunted form of V. v. viviparus. Since the latter's shells reach smaller lengths in rivers (e.g. the Oder river by Frankfurt: 24 mm, Elbe river by Teufelsbrück: 21 mm) and widths (15 to 20 mm) than in lentic waters (e.g. in the low-current Isebek canal by Hamburg: 34 mm). Also the suture depth or the globosity of the up to 5 whorls only, said to be especially pronounced in V. v. penthicus can be explained with the intraspecific variability of this species. As furter recent subspecies Viviparus viviparus costae (MOUSSON 1863) has been described: Description: This geographical form is characterized by a little more globose whorls of the shell, and more contrasting colors. The body shows finer dots than the nominate form. Range, Habitat: Greece (Thrakia),Turkey (regions: Marmara, Black Sea and Eastern Anatolia: e.g. Ýstanbul Baçeköy, Yalova, Ýzmit, Bursa Apolyont Gölü, Ýstanbul Terkos Gölü, Abant Gölü, Sapanca Gölü, Gýcý Gölü, Cernek Gölü), Ukraine (Krim), Caucasus. Was found by ÖKTENER (2004) in the two Turkish lakes mentioned last on various substrates like stones, wood, leaves and aquatic plants.
Literature: FECHTER, R. & FALKNER, G. (1990): Weichtiere. Time-Life Books B.V., Amsterdam. Copyright by Mosaik Verlag GmbH, München. ISBN 3-576034-14-5. [short species description with color photos of live snails and shells of the species and subspecies – in German] GLÖER, P. (2002): Süßwassermollusken Nord und Mitteleuropas. Bestimmungsschlüssel, Lebensweise, Verbreitung. In: Die Tierwelt Deutschlands. Conchbooks, Hackenheim. ISBN 3-925919-60-0. [information about characteristics, range etc. - in German] GLÖER, P & MEIER-BROOK, C. (2003): Süßwassermollusken. Ein Bestimmungsschlüssel für die Bundesrepublik Deutschland. Deutscher Jugendbund für Naturbeobachtung, Hamburg. ISBN 3-923376-02-2. [information about characteristics, location map for Germany – in German]
weblinks: [thread about Viviparus spec. - in German [Food thread for Viviparus spec. - in German [eport about defensive reaction of a Viviparus against a ramshorn snail – in German Atlasproject Nederlandse Mollusken (ANM): Viviparus viviparus (LINNAEUS 1758) Stompe moerasslak. [Location map for the Netherlands CIOBOIU, O. (2003):Diversity of Gastropoda in the Romanian sector of the Danube lower
hydrographic basin. [nformation about the range in Romania on river area levels] [European systematics, information about range] FISCHER, W.: Checklist to Austrian Mollusks / European Viviparidae. [color photos of shells, location information] FUCHS, C. (2002): Cercarien aus Viviparus contectus. [Description of the cercaria found in V. contectus, the cercaria species infesting V. viviparus is mentioned – in German] GLÖER, P. & ZETTLER, M. L. (2005): Kommentierte Artenliste der Süßwassermollusken Deutschlands. Malak. Abh. 23: 3-26. [statement that the status of V. v. penthicus cannot be maintained – in German]] JAKUBIK, B. (2006):Reproductive Pattern of Viviparus viviparus (LINNAEUS 1758) (Gastropoda, Viviparidae) from littoral Aggregations in a through flow Reservoir (Central Poland). Polish Journal of Ecology 54-1: 39-55. [vast examination to the population ecology] ] [database map for V. v. viviparus in Great Britain] ÖKTENER, A. (2004): A preliminary Research on Mollusca Species of some Freshwaters of Sinop and Bafra. G.U. Journal of Science 17(2): 21-30 (2004). ISSN 1303-9709 [nformation on locations and substrates for V. v. costae in Turkey-] VON PROSCHWITZ, T. (2003): Faunistiskt nytt 2002 – snäckor, sniglar och musslo. Göteborgs Naturhistoriska Museum Årstryck 2003: 25-4. [Locations of V. viviparus in Sweden – in Swedish USTAOÐLU, M. R. & BALIK, S. & ÖZBEK, M. (2001):Iþýklý Gölü (Çivril-Denizli)’nün Mollusca Faunasý. - Ege University Press, Volume 18, Issue (1-2): 135-139. ISSN 1300 1590. [also with information about water parameters of one location of V. viviparus in Turkey – in Turkish SLOBODNÍK, J. et al. (2005): Final report on sampling, chemical analysis and ecotoxicological studies. [some locations of V. viviparus et.al. along the Danube are mentioned] SysTax - a Database System for Systematics and Taxonomy [information about locations of collection material] WIESE, V: (1991): Atlas der Land- und Süßwassermollusken in Schleswig-Holstein. Landesamt für Naturschutz und Landschaftspflege Schleswig-Holstein. ISBN 3-923339-40-2. [Location map for Schleswig-Holstein, information about habitat and characteristics – in German] WIESE, V: (Red.) (2007): Systematische Übersicht der Land- und Süßwassermollusken Nord- und Mitteleuropas. [Systematics of European mollusc] YILDIRIM, M. Z. (1995): Türkiye Prosobranchia (Mollusca: Gastropoda) Türleri ve Zoocoðrafik Yayýlýþlarý. 1. Tatlý ve Acý Sular. [information about locations of V. v. costae in Turkey, - in Turkish ] ZETTLER, M. L. (2000): Bewertung des ökologischen Zustandes von Fließgewässern in Mecklenburg-Vorpommern über die Malakofauna als Indikatororganismen. Natur und Naturschutz in Mecklenburg-Vorpommern. 35: 3-36. [good information about the habitats on page 8 – also well comparable with other native species – in German ZETTLER, M. L. et al. (2005): Bemerkenswerte Süßwassermollusken aus Litauen. Aufsammlungen vom September 2004. Malak. Abh. 23: 27-40. [Species locations in Lithuania]
This page was actualized on May 15, 2007 Author: schneckli Translator: Ulrike Bauer
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Bilder/Text/Fotografien sowie Inhalte in Wort/ Text & Bild unterliegen dem © von Alexandra Behrendt Dezember 2004 - 2010 |
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Pictures/texts/photos as well as word, text and pictorial content underlie the copyright of Alexandra Behrendt, December 2004 – 2010.Please note: Any and all photos and pictures are copyrighted!If you are interested in using pictures or photos on private web sites please send me an email. Tax no. 49108/30501 |
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