Radix (Peregriana) tumida (Held, 1836) sensu Kruglov & Starobogatov

(Table 5; fig. 5 H)

Regional distribution. We found SeVeral SpecimenS phenotypically reSembling Radix tumida SenSu KrugloV & StarobogatoV (1993b) in a branch of a riVer inflowing to the Airag Nuur Lake, WeStern Mongolia (See Appendix). Extra-limital distribution. Europe and Siberia (KrugloV 2005; VinarSki & Kantor 2016).

Remarks. KrugloV & StarobogatoV (1993b; KrugloV 2005) deScribe thiS taxon aS a SpecieS of Peregriana conchologically intermediate between Radix balthica and R. ampla (Hartmann, 1821) . The taxonomic diStinctneSS of R. tumida aS well aS itS true identity remain controVerSial. Glöer (2002) treated it aS a Variety of R. auricularia, whereaS moSt WeStern European malacologiStS did not accept it aS a Separate taxon of any rank (e.g. Welther- SchulteS 2012). PoSSibly, R. tumida SenSu KrugloV & StarobogatoV iS a Synonym of Some other SpecieS of the SubgenuS Peregriana .