Larvae die during the third instar stage. Larval brains show a very abnormal, and associated imaginal discs are also abnormal. Larval brains show cells with extreme chromatin condensation, catastrophic anaphases, and polyploidy. Mutants have a mitotic index approximately 7 times that of wild-type with more than half of these exhibiting a polyploid metaphase. In mutant mitotic cells spindles show abnormal centrosomes. Various centrosomal components show varied and abnormal organisation. The γ-tubulin localisation normally seen as the γ-tubulin ring complex is dispersed, cnn localisation remains in discrete bodies but often appears more broadly distributed than in wild-type. The normal juxtaposition of asp and γ-tubulin is no longer seen in mutant spindles and asp is now distributed in a punctate fashion. Cp190 is lost from the poles and accumulates around chromosomes. Centrioles are not always present at the spindle pole, when they are present, there are up to four of them, they vary in size and are not consistently arranged as perpendicular pairs. The numbers of microtubules associating with the poles is also greatly reduced.

Imaginal discs of homozygous larvae are missing or degenerate. Defects in the cell cycle: few or no dividing cells and cell division failures that result in highly polyploid cells.