RK1.
Eyes smaller than normal, surface rough. Hemi- and homozygotes have retinas with slight to moderate disorganization of the ommatidial array, with occasional fused or aberrant ommatidia and missing or condensed rhabdomeres. There is some variation in the structure of the individual neurons of the optic lobe. Within the retina, un1 behaves in a nonautonomous way as indicated by analysis of genetic mosaics.