...,., ...

The number of species known from anchialine cave waters increased from less than 30 in the 1960s (Riedl, 1966) to c. 150 in the 1980s, and close to 400 species in the 1990s. The Table shows species numbers by groups; numbers of known taxa are still increasing rapidly, especially for copepods, but also for amphipods and other groups. Similarly to hypogean waters in general, crustaceans are by far the most prevalent group in anchialine waters. This is evident in the list of known species as well as within any local fauna. Since some crustaceans are larger (except for vertebrates) and more numerous than most other cave inhabitants, Crustacea are also the most important group in relation to biomass. In the Šipun Cave (Cavtat, Croatia; Figure 1) which exhibits a complete salinity range from limnic to polyhaline, nine crustacean species and only six other species have been found. The ratios of individuals and biomass between crustacea and other species is even more striking-at least 10:1. In Cave C-28, on Cape Range Peninsula, Australia, only five species have been found below the pycnocline (the thin layer of a rapid density change), with all but one (a fish) being crustaceans. In the anchialine waters of Quintana Roo, Mexico, 12-14 species have been identified, all of which are crustaceans.