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Ancylastrum Bourguignat, 1853

Diagnostic features

Large limpet-like planorbids with either smooth or spirally ribbed asymmetrical shells. Heterostrophic; apical portion a vestigial spire, projects to right, consisting of an almost complete whorl. Apical region with poorly developed spiral striations. Abrupt change between apex and main body of shell which is limpet-shaped. Mesocone of lateral teeth rounded with small denticles. The copulatory organ has a flagellum, and an accessory bursa is lacking. The penis is biramous with a terminal stylet on one ramus, or uniramous with a subterminal augur-like fold. The bursa copulatrix is spatulate. A rectal ridge is absent (Walker 1988).


Class Gastropoda

Subclass Heterobranchia

Order Hygrophila

Superfamily Planorboidea

Family Planorbidae

Subfamily: Bulininae

Genus Ancylastrum Bourguignat, 1853

Type species: Ancylus (Ancylastrum) cumingianus Bourguignat, J. R. (1853).(=Ancylastrum cumingianus (Bourguignat,1853)).

Original reference: Bourguignat, J. R. (1853). Catalogue des espèces du genre Ancylus. Journal de Concholologie 4: 169-199.

Type locality: Tasmania.

Synonyms: Legrandia Hanley in Legrand, W. 1872; Cumingia Clessin, 1882) Tasmancylus Iredale, 1926.

State of taxonomy

We follow Walker (1988) in this resource.

Biology and ecology

On stones in lakes of the Central Plateau of Tasmania.

Additional information on the biology and ecology of members of this family can be found in Fauna of Australia, vol. 5B, p. 1072-1074.


Tasmania – lakes of the Central Plateau.


A large limpet-like genus of Australian planorbid.

Further reading

Baker, F. C. (1945). The molluscan family Planorbidae. Urbana USA, University of Illinois Press.

Beesley, P. L., Ross, G. J. B. & Wells, A., Eds. (1998). Mollusca: The Southern Synthesis. Parts A & B. Melbourne, CSIRO Publishing. 

Hubendick, B. (1955). Phylogeny of the Planorbidae. Transactions of the Zoological Society of London 28: 453-542.

Hubendick, B. (1964). Studies on Ancylidae: the subgroups. Göteborgs Kungliga Vetenskaps och Vitterhets Samhälles Handligar Sjatte Foljden B 9: 1-72.

Iredale, T. (1943). A basic list of the fresh water Mollusca of Australia. Australian Zoologist 10: 188-230. 

Smith, B. J. (1992). Non-marine Mollusca. Pp. i-xii, 1-408 in W. W. K. Houston. Zoological Catalogue of Australia, 8. Canberra, Australian Government Publishing Service.

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

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

Walker, J. C. (1988). Classification of Australian buliniform planorbids (Mollusca: Pulmonata). Records of the Australian Museum 40: 61-89.