Pitfall trapping was found to be an unreliable way of determining the structure of a Namib Desert epigaeic ant community. There were considerable intra- and interspecific differences in the probability of encountering randomly distributed pitfall traps and in the vulnerability to capture when pitfall traps were encountered. Keywords: Activity rhythm, Intersite/habitat comparisons, Namib Desert, pitfall trapping, structure of epigaeic ant community, temporal changes.