Bmul\αBgtx^Scer\UAS.cYa; Scer\GAL4^GMR.PF late third-instar have disrupted the photoreceptor axon projection patterns reminiscent of semi-permissive temperature phenotypes observed in Cha^ts2 mosaic animals. Axon fascicles form abnormal associations, resulting in unusually large and uneven bundles, instead of the normal continuous R1-R6 growth cone plexus layer. Similar phenotypes are seen when Scer\GAL4^HLHmδ is used as a driver. In the latter case while axons entering the lamina terminate there, the lamina itself is somewhat disorganised. For example, glia are not confined to their proper layers, and can be found extending through the growth cone plexus.