Radix (Peregriana) intermedia (Lamarck, 1822)

Anistratenko, Vitaliy V., Vinarski, Maxim V., Anistratenko, Olga Yu., Furyk, Yurii I. & Degtyarenko, Elena V., 2018, New data on pond snails (Mollusca: Gastropoda: Lymnaeidae) inhabiting the Ukrainian Transcarpathian: diversity, distribution and ecology, Ecologica Montenegrina 18, pp. 1-14 : 12

Radix (Peregriana) intermedia (Lamarck, 1822)

( Fig. 3 , N)

Distribution: One of the widespread pond snails in the region – we found its populations in seven localities ( Table 1). In Ukraine the species is registered in Forest-Steppe and Polissya zones ( Stadnichenko 1982, 2004), recently recorded also in Transcarpathian ( Stadnichenko & Gyrin 2011). General distribution – Palearctic.

Remarks: In the Transcarpathian this species inhabits shallow zone of rivers and canals up to 400 m a.s.l. associating mostly with macrophytes.

Taxonomic remarks: Like R. ampullacea (see above), this species is closely allied to R. balthica and can be distinguished from the latter by its higher spire and more oblong shell. The validity of R. intermedia is accepted in the Russian literature ( Stadnichenko 2004; Kruglov 2005), whereas the Western European malacologists usually consider it as a synonym of R. balthica .

Interestingly, that among the mollusks listed as co-occurring with the pond snails ( Table 1) two records are apparently new for the Transcarpathian region of Ukraine. In a stagnant pool located in Mukacheve district likely Bithynia troschelii (Paasch, 1842) , a regionally new species of the family Bithyniidae was found (locality 7). The shells of this species having convex whorls separated by a deep suture have usually been identified as “ Bithynia leachii ” or ” Bithynia troschelii ” (e.g. Falniowski et al. 2004); more material are necessary to ensure of specimens found identity. Only B. tentaculata (Linnaeus, 1758) was included into the regional malacofauna lists so far ( Zdun 1960).

Finding of Terrestribythinella baidashnikovi in the locality 13 adds the new record for this rare species distribution, only known from a few other Transcarpathian locations so far ( Anistratenko & Stadnichenko 1995; Anistratenko et al. 2017).

Figures

Figure 3. Shells of pond snails found. A – Lymnaea stagnalis from locality 16; B – L. fragilis, locality 7; C – Stagnicola corvus, locality 8; D – Galba truncatula, locality 21; E – G. subangulata, locality 16; F – G. oblonga, locality 4; G, H – Ladislavella terebra, loc. 17; I – Radix auricularia, locality 3; J, K – R. parapsilia, locality 10; L – R. ampullаcea, locality 3; M – R. balthica, locality 2; N – R. intermedia, locality 4; O – R. ampla, locality 15; P – R. tumida, locality 15. Scale bar = 10 mm for A–C and 5 mm for D–P.