The distribution of three species of reptile ticks, Aponomma hydrosauri (Denny), Amblyomma albolimbatum Neumann, and Amb. limbatum Neumann II. Water balance of nymphs and adults in relation to distribution

Three species of reptile ticks have abutting allopatric distributions in South Australia. Aponomma hydvosauri has a greater rate of water loss at normal temperatures than two Amblyomma species. Amb. albolimbatum and Amb. limbatum lose water at the same rate but the former is more resistant to desiccation because it is larger. The two Amblyomma species also have a higher critical temperature above which waterproofing properties of the cuticle break down, but there is no difference in the equilibrium humidities of the three species. There is a general correlation between physiological resistance to desiccation in a species and the aridity of the range of that species. But this correlation does not completely explain the distribution pattern.