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Genus Protocucurbitella

Shell is agglutinated, ovoid, cross section is round. Aperture is circle, denticulate, surrounded by a diaphragm around peristome. Ecology: freshwater. Type species: Protocucurbitella coroniformis Gautier-Lièvre et Thomas, 1960. Note: The taxonomic status of the genus is unclear and widely discussed (Dekhtiar, 1993; Snegovaya, Alekperov, 2010; Patterson, 2014).