Tibetoradix hookeri (Reeve, 1850)

Vinarski, Maxim V., Aksenova, Olga V. & Bolotov, Ivan N., 2020, Taxonomic assessment of genetically-delineated species of radicine snails (Mollusca, Gastropoda, Lymnaeidae), Zoosystematics and Evolution 96 (2), pp. 577-608 : 577

20. Tibetoradix hookeri (Reeve, 1850) Figs 8I ; 9F, G

Lymnaea hookeri Reeve 1850: 49.

Limnaea hookeri - G.B. Sowerby II 1872: pl. XI, fig. 74.

Limnaea hookeri - Annandale and Rao 1925: 167, figs V(7), IX (6).

Lymnaea (Galba) hookeri - Subba Rao 1989: 132.

Tibetoradix hookeri - Aksenova et al. 2018a: 12, figs 6F; 7E, H.

TL.

"Thibetan or north side of Sikkim Himalaya, at 18,000 feet elevation" [Reeve, 1850: 49].

Syntypes.

NHMUK (examined by us). A syntype shell was illustrated by Hubendick (1951) and Aksenova et al. (2018a).

Shell medium-sized (the largest of the two syntypes is 16.9 mm high), with high spire and moderately-inflated body whorl. The shell proportions of T. hookeri resemble those of A. lagotis . The copulatory apparatus is typical for radicines: broad and relatively compact praeputium and very thin and narrow penis sheath (see Fig. 8I ); the ratio of their lengths ranges from 1.25-1.50.

T. hookeri is endemic to China. It occurs in Tibet, known from the upstream section of the Lhasa River and a single additional locality (Brahmaputra River basin), altitude range: 4,540-4,980 m. ( Aksenova et al. 2018a).

Taxonomic remark.

Kruglov and Starobogatov (1993b) classified this species as belonging to the (sub)genus Orientogalba Kruglov et Starobogatov, 1985 and treated it as a senior synonym of Lymnaea heptapotamica Lazareva, 1967, described from southern Kazakhstan. The examination of the syntypes of L. hookeri has shown that L. heptapotamica should not be synonymised with the former species and may well represent a separate taxon, not related to the genus Tibetoradix .

Figures

Figure 8. Copulatory apparatuses of the species in the genera Ampullaceana, Peregriana, Kamtschaticana, Tibetoradix, Racesina, Orientogalba and Bullastra. A. Ampullaceana ampla (11.07.2017, Ukraine, Transcarpathian Region, Irshava River). B. A. balthica (Germany, Mecklenburg-Vorpommern, lake Torgelower See). C. A. dipkunensis (15.09.2016, Ukraine, Transcarpathian Region, Tisa River). D. A. fontinalis (20.08.2017, Russia, Rostov Region, Severskiy Donets River). E. A. lagotis (29.06.2016, Tajikistan, a stream in the Panj River floodplain). F. Peregriana dolgini (13.07.2015, Russia, Tyumen' Region, a floodplain of the Tol'ka oxbow). G. Peregriana peregra (01.07.2006, Russia, Omsk Region, vicinity of Chernoluchye settlement). H. Kamtschaticana kamtschatica (12.04.2014, Russia, Kamchatka Peninsula, Valley of Geysers). I. Tibetoradix hookeri (09 - 10.2012, China, Tibet, a brook, 250 km N of Lhasa). J. T. kozlovi (after Aksyonova et al. 2018 a, modified). K. Racesina oxiana (04.07.2016, Tajikistan, a roadside ditch near Kurban-Shakhid village). L. R. siamensis (24.11.2016, Myanmar, a water reservoir on the Yetho River). M. Ampullaceana relicta relicta (2005, Ohrid Lake). N. Orientogalba ollula (08.07.2010, China, Shaanxi Province, a roadside ditch near Yandi village). O. Bullastra cumingiana (Philippines, Luzon Island, Lake Sampaloc). Scale bars: 1 mm. B - after Schniebs et al. (2011), modified.

Figure 9. Shells of species of the genera Ampullaceana, Kamtschaticana, Myxas, Tibetoradix, Racesina, Orientogalba and Bullastra. A. Ampullaceana relicta relicta (05.1975, Macedonia, a spring near St. Naum monastery, Ohrid Lake region; NHMW). B. A. r. pinteri, a paratype (05.06.1973, Macedonia, Prespa Lake near Perovo; MHMW). C, D. Kamtschaticana kamtschatica (Russia, Kamchatka Peninsula, Valley of Geysers; RMBH). E. Myxas glutinosa (14.09.1963, Kazakhstan, floodplain of the Tobol River near Kustanay City; ZISP). F, G. Tibetoradix hookeri, two syntypes (NHMUK). H. T. kozlovi, the holotype (ZISP). I. Racesina luteola (India, Bengal, Paksay, Pabna; NHMUK). J. R. oxiana (04.07.2016, Tajikistan, a roadside ditch near Kurban-Shakhid village; LMBI). K. R. siamensis (" Thailand "; ZMB). L. Orientogalba viridis, a syntype (Guam Island; NMNH). M. O. ollula (1883, Japan, Yokohama; NHMUK). N. Limnaea bowelli, a type (after Preston 1909). O. Orientogalba cf. bowelli (30.06.1924, China, Tibet, Lingka, 14,500 feet a. s. l.; NHMUK). P. Bullastra cumingiana (Philippine, Cebu Island; NHMUK). Scale bars: 2 mm (C, D, F-H, L, M, O), 5 mm (A, B, E, J-K, N, P).