Unio pictorum ( Linnaeus, 1758 )

Marković, Vanja, Gojšina, Vukašin, Novaković, Boris, Božanić, Milenka, Stojanović, Katarina, Karan-Žnidaršič, Tamara & Živić, Ivana, 2021, The freshwater molluscs of Serbia: Annotated checklist with remarks on distribution and protection status, Zootaxa 5003 (1), pp. 1-64 : 38

80. Unio pictorum ( Linnaeus, 1758)

Findings in Serbia.

Unio pictorum platyrhynchus: Dokić (1882) ; Droüet (1882, 1884); Tadić (1960).

Unio pictorum f. longirostris: Dokić (1882); Droüet (1881, 1884); Tadić (1960).

Unio pictorum: Arambašić (1994) ; Živić et al. (2001); JDS-ITR Report (2002); Paunović et al. (2005, 2006, 2007 a, 2012 a); Tomović et al. (2010 b, 2013, 2014); Tomović (2016); Raković (2015); Novaković (2012); Martinović-Vitanović et al. (2007, 2013); Lucić et al. (2015); Zorić et al. (2020).

Common name. Painter’s mussel.

Morphology. Large bivalve. Shell is elongate-shaped with straight, parallel dorsal and ventral margins, tapered posterior end, and rounded anterior end. It reaches dimensions up to 100 mm (rarely up to 140 mm) in length, 40 mm in height and 30 mm in depth. For more details see Welter-Schultes (2012: 14, figure on the top of the page).

Distribution and ecology. Western Palearctic species widespread in Europe, from the Atlantic to the Ural region, Black and Caspian Sea basins (Van Damme 2011a). Introduced to the Amur Basin, eastern Asia (Graf & Cummings 2021). Commonly found on a muddy substrate in larger lowland rivers ( Aldridge 1999). In Serbia, it mostly occurs in large lowland rivers, canals, lakes and reservoirs, and it has been recorded along almost the entire stretches of the Danube, Sava and Tisza Rivers, and in the lower parts of the Velika Morava and Južna Morava Rivers.

Other remarks. In some parts of its general distribution range the populations of Unio pictorum are declining, while in others it is spreading in smaller waters and reservoirs replacing rare U. crassus Philipsson, 1788 (Welter-Schultes 2012). In Serbia populations of U. pictorum have been spreading in the larger rivers. There are 159 nominal species as synonyms. ( Graf &Cummings 2021). On the IUCN Red List it has been assessed as LC ( Vavrova 2011 c).