The first freshwater molluscs from Wrangel Island, Arctic Russia

Figures & data

Fig. 1  Map of Wrangel Island with the location of the lake studied marked by the red dot.

Fig. 2  (a) An intact specimen of Sibirenauta from Wrangel Island. (b) Soft body of a snail withdrawn from its shell. (c) Shell of the lectotype of S. sibiricus. (d)–(e) The copulatory organ of Sibirenauta from Wrangel Island (photographs and drawing). The following terms are abbreviated: preputium (pp); glandular portion of penis sheath (spg); muscular portion of penis sheath (spm).

Table 1 Morphometric characteristics of shells of Sibirenauta sibiricus from Wrangel Island: shell height (SH), shell width (SW), aperture height (AH) and width (AW), spire height (SpH) and body whorl height (BWH). See Supplementary Fig. S1 for an explanation of the measurements

Character or index	Values (means±standard deviation)
Whorls number	4.00–5.00 (4.44±0.21)
SH (mm)	5.3–7.7 (6.6±0.7)
SW (mm)	2.9–3.9 (3.4±0.3)
SpH (mm)	2.2–3.3 (2.8±0.4)
BWH (mm)	4.2–6.0 (5.2±0.5)
AH (mm)	3.3–4.8 (4.0±0.4)
AW (mm)	1.5–2.4 (2.0±0.3)
SW/SH	0.49–0.55 (0.51±0.02)
SpH/SH	0.38–0.57 (0.43±0.03)
BWH/SH	0.76–0.81 (0.79±0.02)
AH/SH	0.53–0.66 (0.61±0.04)
AW/AH	0.46–0.63 (0.51±0.06)