Embryos derived from swa⁶/Df(1)JF5 females mated to wild-type males often show cuticle defects, ranging from embryos without cuticle and lacking any sign of development (62%), through embryos with a reduction in the number of abdominal segments to embryos that have 8 abdominal segments, with normal or nearly normal abdominal morphology. The most commonly represented cuticular class in embryos that develop is embryos that have 8 abdominal segments, with normal or nearly normal abdominal morphology (69%).

Defects in actin organisation are first detectable at about stage 10 in mutant oocytes. Small irregularly-shaped actin aggregates and actin spheres are seen below the actin-rich cortical layer. Most of the actin spheres are "hollow", having an actin-rich surface and an actin-poor core. About 30% of stage 10 oocytes have a relatively mild mutant phenotype in which a few clumps and spheres are limited to the anterior subcortical layer of the oocyte. About 10% of stage 10 egg chambers have a larger number of aggregates and spheres which are distributed throughout the oocyte and fused actin spheres. About 60% of oocytes between stages 11 to 14 have detectable defects in actin organisation. In these abnormal oocytes, actin spheres about 3-5μm in diameter are uniformly distributed from the subcortical layer into deeper central cytoplasm. The spheres are more numerous in later stages of oogenesis and a larger fraction of them are hollow. Occasional "double" spheres consisting of two spheres fused at their surface are seen. Tiny actin granules are visible on the surface of the spheres.

Excess of irregularly shaped internal chromatin masses, and chromatin condensation is asynchronous. During preblastoderm and early blastoderm cleavages lagging chromosomes during anaphase are common. Pregastrula and gastrula embryos exhibit nuclear defects, an excess of irregularly shaped internal chromatin masses, blastoderm nuclei are non-uniform in size and chromatin condensation and asynchronous in the cell cycle.

No surviving offspring: defects in cephalopharyngeal apparatus. Many embryos have abdominal segment fusions or deletions.

maternal-effect lethal female-sterile.