The groundwater fauna (stygofauna) of the Pilbara region of Western Australia is diverse and largely endemic. Extensive mining in the region poses a potential threat to this fragile ecosystem. Knowledge of the dispersal capabilities of groundwater species will aid in managing both fauna and resources. Ten polymorphic microsatellite loci were used to assess variability in 27 specimens of the groundwater amphipod Chydaekata sp. from Marillana Creek in the Pilbara. The number of alleles ranged from 3 to 15, and observed heterozygosity ranged from 0.077 to 0.885. Nine loci were in HWE, and no pairs of loci showed evidence of linkage. The loci will be useful for aiding the management of stygobitic populations in a disturbed landscape, by understanding dispersal patterns and gene flow within and between tributaries.