Expression is first observed in the third instar larval eye imaginal disc at row 8 in a single photoreceptor located in the center of all ommatidia. Expression becomes more robust at row 14-15 after the morphogenetic furrow. Expression is restricted to a single photoreceptor cell per ommatiduium. Co-localization with sens show R8 specificity. Expression is observed in R8 cells in 48 hr APF pupae and is sometimes observed in an additional photoreceptor in some ommatidia. No expression is observed in R8 in the adult retina but some expression is observed in laminar neurons.