Homozygous larvae are negatively photokinetic with a stimulus indice significantly higher than wild type control. Heterozygotes have an indice similar to wild type, transheterozygotes with lphA2 have a higher indice. Homozygotes respond normally to light in a phototaxis assay, ERG is normal, males perform vigorous courtship in response to wild type females and perform the behaviour 'orientation', rarely performed by blind or visually impaired males. Hemizygotes are blind. Mutation does not affect larval responses to olfactory or taste stimuli.
Larvae are blind or show reduced response in a photokinesis assay. Adults have a wild type visual behaviour with respect to courtship, and normal ERGs.
P-element can be excised by transposase.