This species is characterised by its slender, straight, evenly spaced axial ribs with a chain of subsutural grain-like nodules.
Sermyla onca (A. Adams & Angas, 1864)
Class Gastropoda
Infraclass Caenogastropoda
Megaorder Cerithiimorpha
Order Cerithiida
Superfamily Cerithioidea
Family Thiaridae
Genus Sermyla A. Adams & Angas, 1864 (Type species: Melania mitra Dunker, 1844 = Sermya riquetii (Grateloup, 1840)
Original name: Melania (Melasma) onca A. Adams & Angas, 1864. In Adams, A. & Angas, G. F. (1864). Descriptions of new species of freshwater shells collected by Mr. F.G. Waterhouse during J. McDonald Stuart’s overland journey from Adelaide to the north-west coast of Australia. Proceedings of the Zoological Society of London 1863: 414-418.
Type locality: North Australia, tributary of Adelaide River, Northern Territory.
Lives on sandy or stony substrata in the upper and middle sections of seasonal rivers and creeks. Diet consists of detritus and algae. Brood pouch contains a high number (>150) of juveniles in various stages of development.
Tropical wet northern part of the Northern Territory, but inland from the coast.
Listed as Melasma onca in previous versions of this key.
Beesley, P. L., Ross, G. J. B. & Wells, A., Eds. (1998). Mollusca: The Southern Synthesis. Parts A & B. Melbourne, CSIRO Publishing.
Glaubrecht, M., Brinkmann, N. & Pöppe, J. (2009). Diversity and disparity ‘down under’: systematics, biogeography and reproductive modes of the ‘marsupial’ freshwater Thiaridae (Caenogastropoda, Cerithioidea) in Australia. Zoosystematics and Evolution 85: 199-275.
Glaubrecht, M. & Neiber, M. T. (2019). Thiaridae Gill, 1871 (1823). Pp. 86-89 in C. Lydeard & Cummings, K. S. Freshwater Mollusks of the World: a Distribution Atlas. Baltimore, John Hopkins University Press.
Lentge-Maaß, N., Neiber, M. T., Gimnich, F., & Glaubrecht, M. (2021). Evolutionary systematics of the viviparous gastropod Sermyla (Gastropoda: Cerithioidea: Thiaridae), with the description of a new species. Zoological Journal of the Linnean Society 192(3): 736-762.
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.
Maaß, N. & Glaubrecht, M. 2012. Comparing the reproductive biology of three “marsupial”, eu-viviparous gastropods (Cerithioidea, Thiaridae) from drainages of Australia’s monsoonal north. Zoosystematics and Evolution 88: 293–315.
Willan, E. C. & Kessner, V. (2021). A conspectus of the freshwater molluscs of the Daly River catchment, Northern Territory. Northern Territory Naturalist 30: 108-137.
