The percentage of maternal effect embryonic lethality seen in embryos derived from orbmel homozygous females is increased by heterozygosity for one of wisp89, wisp40, wispKG05287, hrgPAP45 or hrgPAP21. The percentage of ventralised embryos is not increased by heterozygosity for one copy of wisp89, wisp40 or wispKG05287, but is enhanced by heterozygosity for one copy of hrgPAP45 or hrgPAP21.
hrgPAP21/+; orbmel and hrgPAP45/+; orbmel lay almost no eggs. In these females oogenesis stops most frequently at stage 7/8 after which egg chambers degenerate, even though one or two stage 14 oocytes per ovary can be observed.
The failure of many eggs derived from orbmel females to hatch is suppressed by ypsJM2/ypsJM2. The failure of most eggs derived from orbmel/orbF303 females to hatch is partially suppressed by ypsJM2/ypsJM2 (40% of eggs derived from the double mutant females hatch). The failure of eggs derived from orbmel/orbF343 females to hatch is very weakly suppressed by ypsJM2/ypsJM2; rare escapers complete embryogenesis and hatch. Eggs laid by ypsJM2 orbmel/ypsJM2 orbF303 females have fused, reduced or absent dorsal appendages. 5% of ypsJM2 orbmel/ypsJM2 orbF303 egg chambers are bipolar.