Homozygous third instar larvae are normal in overall size, but the eye and antennal imaginal discs are dramatically diminished in size in these animals.

Homozygous clones in the eye are smaller than control clones. Ommatidia that are mosaic for bdg⁹⁰ show two different mutant phenotypes (although the majority of mosaic ommatidia are phenotypically wild type). Firstly, numerous ommatidia on clonal borders are missing photoreceptors. Secondly, symmetric mosaic ommatidia are seen, although these are rare. These symmetric ommatidia are always mosaic for the R3/R4 pair. The majority of the symmetric ommatidia are of the R4/R4 type although R3/R3 ommatidia are also found.