Parasitism affects all taxa and influences individual and population success. Parasitism of adult dragonflies is widespread and frequently includes gregarine (Apicomplexa) life stages in the gut of the host. This research investigates variation in gregarine parasite prevalence and load in c? versus 2 adults of Erythemis simplicicollis and Brachymesia gravida associated with 2 central Texas reservoirs in close proximity. Parasite prevalence was biased toward <J 6 E. simplicicollis and toward 9 2 B. gravida. Results suggest that gender bias in parasite prevalence is influenced by gender behavior and environment more so than by immuno-response differences between genders.