摘要：Records of five native and one alien gammarid species are reported from fifteen sites along the entire course of the Una River. Samples of gammarids were collected at ten sites in the main course, and at four sites in small left tributaries of the Una River during field studies conducted from 2005 to 2009. Two endemic species formerly known only from the Adriatic Sea drainage area, Echinogammarus acarinatus and Fontogammarus dalmatinus, were collected for the first time in the Black Sea drainage area at the main spring and in the upper course of the Una River. All three Gammarus species that occur in Croatia have been found in the Una River. Only G. balcanicus was recorded at the upper course, while both G. fossarum and G. roeseli were found in the middle and lower river course. With five gammarid species recorded, the Una River has the highest freshwater gammarid species richness among all of the Croatian watercourses. The new record of the invasive Ponto-Caspian gammarid, Dikerogammarus haemobaphes, in the Sava River at the mouth of the Una River is also reported and discussed.
关键词：Amphipoda; Gammaridae; Pontogammaridae; endemic; invasive species; distribution; Una River
