Abstract

The freshwater anomuran crabs of the genus Aegla are widespread throughout lakes and rivers in central and southern Chile. They form an important component of the benthic fauna, because the species of the genus are shredders of organic debris and also make an important prey for native and introduced fishes. Nevertheless, the ecology of this genus has been poorly studied in lakes in comparison to rivers. The aim of the present study was a description of the spatial pattern of distribution of an Aegla rostrata population from the littoral zone of Pullinque Lake, in the north of Chilean Patagonia. The results revealed a low density (1.0 +/- 0.8 ind/m(2)), that had a uniform pattern, and has a positive binomial distribution. The results would indicate that the studied species would have territorial behaviour that would be associated with interspecific resource competition. The observed results would agree with observations for the benthic zones in Chilean Patagonian lakes, where Aegla would show territorial behaviour.