The karst areas in Croatia, part of the Dinarides, have been defined biospeleologically as an area of high biodiversity in world terms, covering 26 thousand km2 in all. In this monograph we give data about the biodiversity of subterranean habitats and their biota primarily from a taxonomic perspective with special attention being paid to regional diversity. The diversified geomorphology, hydrology and climate have resulted in a remarkable range of different underground habitats in Croatia, viz. inland and coastal caves, superficial and deep phreatic networks, interstitial – hyporheic substrates and other infiltration zones, etc. In Croatia more than 500 obligate subterranean species and subspecies are known from caves and interstitial habit...