The brains of hemizygous larvae have a reduced frequency of anaphase figures, and an increased frequency of polyploid figures and overcondensed chromosomes compared to wild-type. The brains are very small compared to wild-type and there are no recognisable imaginal discs.
Primary defect is an inability of centrosomes to separate and organise a bipolar spindle. Mitotic figures are highly polyploid consisting of overcondensed chromosomes in apparent monopolar configurations.
Klp61F alleles form the following phenotypic series, from the most to the least severe: Klp61Furc-1 > Klp61Furc-3 > Klp61F06836, Klp61F07012 > Klp61F06345 > Klp61Furc-4.