Radix (Peregriana) tumida (Held, 1836)

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 : 11

Radix (Peregriana) tumida (Held, 1836)

( Fig. 3 , P; 4 , C)

Distribution: The species is new for the Transcarpathian region; found in 3 localities (12, 15, 18 – Table 1). In Ukraine the species registered in all regions ( Stadnichenko 2004) though not mentioned in Transcarpathian so far ( Stadnichenko & Gyrin 2011). General distribution – Northern Palearctic.

Remarks: In the Transcarpathian this species is found only in rivers among vegetation.

Taxonomic remarks: From the conchological point of view, R. tumida resembles R. ampla but differs from the latter by higher spire and less inflated aperture. Besides, Kruglov (2005) reported some differences in the proportions of the copulatory organs of these two snails. As it was stated above, the penis sheath in R. ampla is a bit longer than the preputium, whereas in R. tumida one may observe an opposite state. According to Kruglov (2005), the praeputium of R. tumida is around 1.7 times longer than the penis sheath. The copulatory apparatus of the R. tumida species dissected by us has essentially the same proportions (see Fig. 4 , C).

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.

Figure 4. The copulatory organs of some lymnaeid snails from the Transcarpathian region. A – Ladislavella terebra; B – Radix ampla; C – R. tumida. Scale bars = 1 mm for A and 2 mm for B, C. Abbreviations: pp – praeputium, ps – penis sheath.