20. Bithynia tentaculata (Linnaeus, 1758)

Findings in Serbia.

Bithynia (Bithynia) tentaculata: Karaman & Karaman (2007).

Bithynia tentaculata: Hesse (1929); Tomić (1959); Matoničkin et al. (1975); Frank et al. (1990); Jovanović (1990); Arambašić (1994); Karaman (2001); Jakovčev-Todorović et al. (2005); Jović et al. (2006); Paunović et al. (2007a, 2008, 2012 a); Marković et al. (2012, 2015); Martinović-Vitanović et al. (2013); Novaković (2013, pers. comm. 2015); Stojanović (2017).

Common name. Faucet snail, common bithynia, mud bithynia.

Morphology. Small-sized snails (conical shell up to 10–11 mm high). Yellowish shell has 5 whorls with deep suture. Operculum and aperture are acute-ovate, uumbilicus is closed. For more details see Welter-Schultes (2012: 38, figure on the top of the page).

Distribution and ecology. West Palearctic species common in slow-flowing and standing waters. The snail inhabits both permanent and temporary waters, yet it prefers muddy substrate with dense vegetation, increased water conductivity and plenty of nutrients (Welter-Schultes 2012; Glöer 2019. In Serbia, the species is present in all major drainages (rivers, canals, ponds/lakes), while in large rivers such as the Danube, Sava, Tisza and Velika Morava Rivers, populations can be quite abundant. Besides slow-flowing lowland rivers the species is found in medium-sized and smaller hilly-mountainous watercourses as well [Zapadna Morava River (Novaković 2013), Vrla, Rača, Crnica and Mlava Rivers (Stojanović 2017)]. Welter-Schultes (2012) reports the presence of this species up to 1400 m.a.s.l. (Switzerland), while in Serbia it reaches 1000 m.a.s.l. (Stojanović 2017).

Other remarks. Sometimes an individual snail lives a year longer than its usual life span of 12–24 months. Long-living individuals can be found in any population, they have an additional whorl, and they are described as Bithynia . tentaculata f. producta Menke 1828. Some authors even consider it as a valid species (Glöer 2019). Introduced and invasive species in North America (Kipp et al. 2021). On the IUCN Red List it has been assessed as LC (Seddon 2011 c)