We have shown that target site insensitivity in Australian Aphis gossypii via the R81T mutation is not the causal mechanism of neonicotinoid resistance despite overseas studies implicating such. Instead we propose metabolic detoxification as the likely causal mechanism for resistance in Australian A. gossypii and we are currently trying to validate that hypothesis via transcriptome analysis. It is not clear why the R81T mutation is absent but the difference may relate to limited imidacloprid use in Australian cotton and the progressive nature of the cotton industry itself.