Vodní malakofauna p ítok Javorky u Lázní Bělohrad Aquatic molluscan fauna of tributaries of the brook Javorka near Lázně Bělohrad (East Bohemia, Czech Republic)

This paper presents results of a malacological survey of four small tributaries of the brook Javorka near Lázně Bělohrad in East Bohemia (Czech Republic). Only 15 species of aquatic molluscs (7 gastropods, 8 bivalves) were found at 31 sites during research realised in 2010, 2011 and 2012. Molluscan assemblages of all tributaries were similar and consisted of common and widespread molluscs as Galba truncatula, Radix peregra, Anodonta anatina, Pisidium subtruncatum or P. casertanum. The occurrence of endangered river pea mussel (Pisidium amnicum) was confirmed at three tributaries but only at lower parts near its inflows to the brook Javorka. The research was focused on the endangered thick-shelled river mussel (Unio crassus), and the occurrence of numerous population was confirmed at the brook Lukavecky potok. In the brook Chote sky potok a small population of this bivalve was found. Only a few specimens were found at remaining two tributaries.