The benthic crustaceans do not have random spatial distribution under natural conditions, this means that these species can have a determined pattern such as associated or uniform. In this work we studied a non-random spatial pattern in two freshwater malacostracan species, Aegla cholchol (Decapoda) from Cautin river, and Hyalella patagonica (Amphipoda) from Quillel-hue lake (38 degrees S, Araucania Region, Chile) respectively. The data revealed that both species have an associated pattern, and negative binomial distribution. These results agree with similar observations for other inland water benthic species from Southern Chilean rivers and streams. (C) 2017 Production and hosting by Elsevier B.V. on behalf of King Saud University.