FlyBase curator comment: this entry is used to capture phenotypic information when the particular allele (or allele combination) used by the author could not be determined but the context of the experiment suggests that the phenotype being described is some kind of loss of function.
At 50% of pupal development the actin-based microvilli in chpunspecified mutant photoreceptor cells are irregularly arranged and loosely packed compared to the tightly packed rows in wild type pupae.
Quantum bump amplitudes are not significantly different from wild type amplitudes.