DISTRIBUTIONAL PATTERNS OF FRESH-WATER DECAPODA (CRUSTACEA, MALACOSTRACA) IN SOUTHERN SOUTH-AMERICA - A PANBIOGEOGRAPHIC APPROACH

A panbiogeographic analysis based on the track compatibility method wa s the starting point for analysing historical biogeographic patterns a mong freshwater Decapoda (Crustacea: Malacostraca) in southern South A merica. Based on distributional data of three groups, namely Parastaci dae (Astacidea), Aeglidae (Anomura) and Trichodactylidae (Brachyura), eight areas of endemism were defined. The panbiogeographic analysis le d to recognition of one generalized track, with a northern part includ ing north western Argentina, Paraguay, Parana and Uruguay Rivers and s outhern Brazil; and a southern part, including central and southern Ch ile, the endorheic Subandean region, and extra-andean Patagonia. The d irection of the track shows the past southward expansion of the tropic al freshwater fauna.