Hemibranch preference by freshwater monogeneans a function of gill area, water current, or both?

Differences in the occurrence of monogeneans on lamellae of fish gill arches were observed in this study. These differences were attributed to variations in water current on the gill surfaces or to greater area of certain arches. Two computer simulation programs based on gill area and water current were written to generate parasite metapopulations with clumped patterns. The results obtained were compared with true distributions of selected freshwater monogenean taxa. The combination of both theoretical models (gill area and water current) had greater explanatory power than either of the models alone.