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Potamopyrgus antipodarum (Gray, 1843)

Diagnostic features

Shells can be quite variable, and different forms include smooth with convex whorls, keeled, or with a peripheral periostracal spiral ridge or periostracal hairs. This species has a white smear on the inside of the operculum, does not develop a thickened aperture and females (all or nearly all of the population) have brooded embryos in the pallial oviduct in the mantle cavity.


Potamopyrgus antipodarum (Gray, 1843)

Common name: Mud Snail (in Europe)

Class Gastropoda

Subclass Caenogastropoda

Order Littorinimorpha 

Superfamily Truncatelloidea

Family Tateidae

Genus Potamopyrgus Stimpson, 1865

Original name: Amnicola antipodarum Gray, 1843. Gray, J. E. (1843). Catalogue of the species of Mollusca and their shells, which have hitherto been recorded as found at New Zealand, with the description of some lately found species. In Dieffenbach, E.,Travels in New Zealand 2: 228-265.

Type locality: New Zealand.

Synonyms: Previously known in Australia as Potamopyrgus niger* and in Europe as Potamopyrgus jenkinsi. There are many synonyms of this species, including several based on Australian material. A full list has been given by Ponder (1988).

* see Austropyrgus niger.

Biology and ecology

On wood, stones, sediment and water weed; often very abundant. Feeds on bacteria and microalgae. Parthenogenic, although some populations contain some males. Broods embryos in modified pallial oviduct.

P. antipodarum lives in polluted and unpolluted streams, lakes and drains in urban and rural areas. It lives on most kinds of substrate including on the inside of water pipes and water reticulation systems. Species feed on bacteria, microscopic algae, diatoms and, possibly, decaying vegetation. P. antipodarum is ovoviviparous,and parthenogenic and has become a pest wherever it has been introduced, often reaching enormous population densities.

Additional information on the biology and ecology of members of this family can be found in Fauna of Australia, vol. 5B, p. 752-755.


Introduced from New Zealand; found throughout south-eastern Australia and Tasmania, although distribution in New South Wales is very patchy and not known to extend north of Newcastle. It is common in streams in most parts of Sydney.

It is also introduced to Europe and the UK, and to parts of North America.


This New Zealand species has become established in New South Wales, Victoria, South Australia and Tasmania. When present it can be extremely abundant.

The invasion of Europe, North America, Asia and SE Australia by the ovoviviparous, parthenogenic Potamopyrgus antipodarum is well documented in the literature. In Europe the species had been named Potamopyrgus jenkinsi (Smith).  

Further reading

Haase, M. (2008). The radiation of hydrobiid gastropods in New Zealand: a revision including the description of new species based on morphology and mtDNA sequence information. Systematics and Biodiversity 6: 99-159.

Jokela, J., Lively, C. M., Fox, J. A. & Dybdahl, M. F. (1997). Flat reaction norms and" frozen" phenotypic variation in clonal snails (Potamopyrgus antipodarum). Evolution 51: 1120-1129.

Dybdahl, M. F. & Lively, C. M. (1996). The geography of coevolution: comparative population structures for a snail and its trematode parasite. Evolution 50: 2264-2275.

Ng, T.H., Tan, S.K., Wong, W.H., Meier, R., Chan, S-Y., Tan, H.H. and Yeo, D.C.J. 2016. Molluscs for Sale: Assessment of Freshwater Gastropods and Bivalves in the Ornamental Pet Trade. PLOS One. DOI:10.1371/journal.pone.0161130.

Ponder, W. F. (1988). Potamopyrgus antipodarum: a molluscan colonizer of Europe and Australia. Journal of Molluscan Studies 54: 271-285.

Ponder, W. F., Clark, S. A. & Dallwitz, M. J. (2000). Freshwater and estuarine molluscs: an interactive, illustrated key for New South Wales. Melbourne, CSIRO Publishing.

Schreiber, E. S. G., Glaister, A., Quinn, G. P. & Lake, P. S. (1998). Life history and population dynamics of the exotic snail Potamopyrgus antipodarum (Prosobranchia: Hydrobiidae) in Lake Purrumbete, Victoria, Australia. Marine and Freshwater Research 49: 73-78.

Smith, B. J. & Kershaw, R. C. (1979). Field guide to the non-marine Molluscs of South-eastern Australia. Canberra, A.N.U. Press (as Potamopyrgus niger).

Smith, B. J. & Kershaw, R. C. (1981). Tasmanian Land and Freshwater Molluscs. Hobart, University of Tasmania (as Potamopyrgus niger).

Wallace, C. (1978). Notes on the distribution of sex and shell characters in some Australian populations of Potamopyrgus (Gastropoda: Hydrobiidae). Journal of the Malacological Society of Australia 4: 71-76.

Wallace, C. (1980). Sex in Potamopyrgus (abstract). Journal of the Malacological Society of Australia 4: 263.

Wallace, C. (1992). Parthenogenesis, sex and chromosomes in Potamopyrgus. Journal of Molluscan Studies 58: 93-107.

Winterbourn, M. (1970). The New Zealand species of Potamopyrgus (Gastropoda : Hydrobiidae). Malacologia 10: 283-321.

Winterbourn, M. J. (1969). Water temperature as a factor limiting the distribution of Potamopyrgus antipodum (Gastropoda-Prosobranchia) in the New Zealand thermal region. New Zealand Journal of Marine and Freshwater Research 3: 453-458.

Winterbourn, M. J. (1970). Population studies on the New Zealand freshwater gastropod, Potamopyrgus antipodarum (Gray). Proceedings of the Malacological Society of London 39: 139-149.

Winterbourn, M. J. (1972). Morphological variation of Potamopyrgus jenkinsi (Smith) from England and a comparison with the New Zealand species, Potamopyrgus antipodarum (Gray). Proceedings of the Malacological Society of London 40: 133-145.