摘要：This paper presents the results of probably the first rather detailed survey of aquatic molluscs of Rab Island. This island belongs among those Croatian islands situated in the northern Adriatic Sea. Altogether 11 species of aquatic non-marine molluscs (9 gastropods, 2 bivalves) were found at 49 sites in 2012-2015. Two species recorded, Ecrobia ventrosa and Myosotella myosotis, inhabit brackish waters while the other species belong among freshwater molluscs and were found in springs, wells, ditches, rivulets and small brooks. Kerkia kareli, a species described in 2014 from Pag Island which inhabits phreatic waters, was found at one site. The non-native Physella acuta was recorded from many sites and this find is probably the first known occurrence of a non-native aquatic mollusc at least from the northern Croatian islands. The results of this research were compared with aquatic molluscan assemblages of other Croatian islands.
