Characterisation, analysis of expression and localisation of the opsin gene repertoire from the perspective of photoperiodism in the aphid Acyrthosiphon pisum.

•A. pisum opsin expression increases under short photoperiod conditions.•Opsins are expressed in eyes, optic lobes and protocerebrum.•Opsin expression tends to be higher at night.•Some opsins might be expressed in clock neurons.