Genus Kamtschaticana Kruglov & Starobogatov, 1984

Kruglov & Starobogatov, 1984: 30.

Type species: Lymneus kamtschaticus Middendorff, 1850 (by original designation).

Diagnosis: Shell typically small (≤ 12 mm in height, rarely larger), spheroid to ovate-conical, with low spire and conspicuously inflated body whorl. Whorls are visibly convex and rounded. Prostate with a single internal fold. Praeputium dark-pigmented, sac-like; it is much wider than the penis sheath. The ratio of the lengths of these structures slightly exceeds 1.0 (i.e. praeputium is slightly longer than penis sheath). The penial knot is absent. The spermathecal duct is short.

Species richness: In addition to the type species, we describe another species herein, K. nipponica. We found another candidate species in Lake Azabachye in Kamchatka. However, this is known from only a single sequenced specimen, and we refrain from its description but refer to it as Kamtschaticana sp.1 (Fig. 5M). Vinarski et al. (2021) provided additional detail on the taxonomy and species composition of Kamtschaticana.

Distribution: The type species, K. kamtschaticana (Figs 4G, 5K, L), is widely distributed in northeast Asia and in the Russian Far East and the southern parts of Eastern Siberia. The findings of this species from Alaska are also known (Vinarski et al. 2021). With the description of K. nipponica, the range of the genus extends to Japan (Hokkaido Island), although there are no records of Kamtschaticana from the Kurile Islands.