Retina defects are associated with optic lobe defects in 100% of homozygous N^fa-fx retina clones generated by somatic recombination. The arrangement of ommatidia is severely disrupted, the number of ommatidia is reduced and they appear shorter than normal in homozygous clones in the retina. A disruption of the fenestrated zone, laminar cortex and neuropil can be seen in the underlying optic lobe. Homozygous late pupae have normal optic lobe morphology, but the lamina neuropil is severely disrupted, containing large vacuoles, and the medulla neuropil contains small vacuoles in homozygous adults.

Strong echinus-like eyes, darkening with age with glistening frosted appearance. Homozygous females sterile, but sterility may be separable from N^fa-fx (Kaplan and Hayes, 1967). strong allele; not dosage compensated