Almost no eggs laid by heterozygous females display a fused dorsal appendage phenotype.

"Bic-D[mom]" (Bic-D mid-oogenesis mutant) females (BicD^r8/Df(2L)TW119 females carrying BicD^hs.PS in which regular heat shocks (two 37[o]C 30 minute heat shocks per day for 3-4 days starting in the third larval instar/early pupal stage) have been used to overcome the developmental lethality associated with BicD^r8/Df(2L)TW119, and then the adults have been transferred to 18[o]C to stop BicD^hs.PS expression) lay eggs with phenotypes ranging from partially fused or fused dorsal appendages to reduced or absent dorsal appendages. In many cases, the dorsal appendage remnants are located more posteriorly on the eggshell than normal. The operculum is often reduced or missing, and small eggs lacking the anterior chorion are also seen.

Fertile over BicD¹, and viable but sterile over BicD^r or BicD^R26. Lethality is complete at 29^oC, but some adults escape at 18^oC. Survival can be markedly improved by raising the flies on apple juice-agar medium supplemented with live yeast. Resulting adults are uncoordinated and generally die within a couple of days. Ovaries contain only egg chambers with 16 polyploid nuclei and no oocyte. Germ line clones give rise to 16-nurse cell chambers with no oocyte. Reorganization of ring canals does not occur. The largest ring canal does not move to the posterior end of the cluster and is found in apparently random positions in the posterior half of the egg chamber.