River gudgeons (multiple Romanogobio species)

Features

R. belingi (Belingi's river gudgeon): a shoaling bottom fish of sandy to gravelly lowland rivers, feeding on bottom-dwelling invertebrates; spawns in batches from May-June at around 15°C. Found in the southern Baltic basin (Oder, Vistula) and North Sea basin (Elbe, Rhine). R. vladykovi (Vladykov's river gudgeon): lives in faster-flowing, sandy piedmont rivers, shoaling, diurnal, feeding on bottom-dwelling invertebrates. Found in the Danube basin, in Germany in the Danube and its tributaries.