Two Asian freshwater snails newly introduced into South Africa and an analysis of alien species reported to date Author Appleton, C. C. Author Miranda, N. A. F. text African Invertebrates 2015 2015-01-21 56 1 1 1 http://www.bioone.org/doi/10.5733/afin.056.0102 journal article 10.5733/afin.056.0102 2305-2562 7649964 Key to the Lymnaeidae in South Africa Four lymnaeid species occur in South Africa ; L. natalensis , Galba truncatula (O.F. Müller, 1774) and the invasive Pseudosuccinea columella (Say, 1817) and R. rubiginosa . They may be separated using the following key: 1 Shell ovate, basal whorl markedly swollen, spire usually much lower than the aperture....................................................................................................................3 – Shell slender, basal whorl not markedly swollen, spire usually not more than half the apertural height..................................................................................................2 2 Shell with reticulate sculpture, spire up to half as high as aperture.......................... ............................................................................. Pseudosuccinea columella (Say) – Shell without reticulate sculpture, spire about as high as aperture ........................... ............................................................................... Galba truncatula (O.F. Müller) 3 Mantle uniformly pigmented except for numerous small discrete spots, partially pigmented with small unpigmented spots and larger blotches, shell not robust, outer margin of basal whorl curved, aperture wide.............. Lymnaea natalensis Krauss – Mantle partially pigmented with small unpigmented spots and larger blotches, shell robust, outer margin of basal whorl nearly straight so that aperture is relatively narrow ....................................................................... Radix rubiginosa (Michelin)