Mutant embryos show an increase in the number of dorsal, dorsolateral and lateral adult muscle precursor cells compared to wild type. The number of ventral adult muscle precursor cells is unaffected in these embryos.
Surviving transheterozygotes with Whid-A22 or Whid-A206 have an abnormal wing phenotype. The mutant wing appears opaque by comparison to wild type and occasionally contains trapped fluid. Transheterozygous males also possess improperly positioned terminalia. Some hemizygotes die before hatching and most of those that hatch possess properly formed cephalopharyngeal skeleton.