Radix (Radix) bactriana (Hutton, 1849)

Marinskiy, Vadim V., 2017, Checklist of the freshwater snails (Mollusca: Gastropoda) of Mongolia, Zootaxa 4317 (1), pp. 45-78 : 56-57

Radix (Radix) bactriana (Hutton, 1849)

( fig. 4 H)

Regional distribution. In SampleS examined by uS, Radix bactriana waS repreSented by SeVeral hundredS of SpecimenS collected mainly in large mountain lakeS of WeStern Mongolia (Khoit-Dalai Nuur, Khar US Nuur, Nogoon Nuur and otherS) aS well aS in large riVerS (Kherlen, Kharaa gol). Limnaea auricularia morpha kosogolensis Lindholm, 1929 (fig. 5 A) from the HöVSgöl Lake may alSo be identified with R. bactriana on the baSiS of itS rounded whorlS. ZIN collection containS numerouS SampleS of SnailS from VariouS partS of Mongolia claSSified by LazareVa (1967) aS R. auricularia bactriana . ThuS, the SpecieS SeemS to occur throughout the country excluding itS Southern deSert partS. The Spectrum of habitatS where R. bactriana dwellS SeemS to be a bit narrower than that of R. auricularia . In particular, R. bactriana iS not found in floodplain lakeS and Semi-permanent waterbodieS.

Extra-limital distribution. LazareVa (1967) diStinguiShed SeVeral SubSpecieS of R. auricularia liVing in KazakhStan and neighbouring areaS of Central ASia. One of them waS R. auricularia bactriana (Hutton, 1849) thought to inhabit AfghaniStan, Iran and mountain areaS of Central ASia ( LazareVa 1967; LikhareV & StarobogatoV 1967). Later on, KrugloV & StarobogatoV (1993a) ranked it aS a Separate SpecieS cloSely related to R. auricularia .

Morphology. R. bactriana can de diStinguiShed from R. auricularia by different Shape of the Spire and the degree of whorlS conVexity (flattened in R. auricularia , eVenly conVex or rounded in R. bactriana ). HoweVer, the phenotypic diStance Separating the two SpecieS iS rather Short (including almoSt identical Structure of the reproductiVe SyStem; See KrugloV & StarobogatoV 1993a; KrugloV 2005). Shell proportionS are Similar (See Table 4), and the SpecieS StatuS of R. bactriana haS to be checked by meanS of a molecular Study.

* Above lines—maximum and minimum values; below lines—mean values ± standard deviations.

Figures

FIGURE 4. Shells and genitalia of the lymnaeid snails discUssed in the paper. A— Lymnaea stagnalis (31.07.1982, floodplain of the Orkhon River, leg. Mikhailov). B— L. stagnalis (15.07.2012, Chono-Khoraikhgol River, leg. Vinarski). C— Ladislavella terebra (31.07.1982, floodplain of the Orkhon River, leg. Mikhailov). D, E— Galba sibirica (19.07.2012, Teellin-gol River, leg. Vinarski). F— G. truncatula, the copUlatory apparatUs (25.02.2010, Abkhazia, Gagra District, Wet shore of Inkit Lake, leg. Palatov). G – Radix auricularia (19.07.2012, Teellin-gol River, leg. Vinarski). H— Radix bactriana (13.07.2012, Khar Us NUUr Lake, leg. Vinarski). I— R. parapsilia (09.06.2009, Khovd River, leg. Maryinskiy). J— R. mongolica (13.07.2012, Khar Us NUUr Lake, leg. Vinarski). K— R. mongolica, a scalarid specimen (Hövsgöl Lake, leg. et det. Sitnikova, LIN). L— R. balthica (20.07.1967, Khar Dorgon NUUr Lake, leg. Zhaltsanova). M— R. intermedia, a paralectotype of Limnaea eversa (1877, Eter River near Dja-Dzassyk Monastery, leg. Potanin, ZIN). Scale bars 1 mm (E, F), 2 mm (C, I, J, K), 5 mm (A, B, G, H, L, M).