Heterozygous females deposit few, mostly flaccid eggs that do not have dorsal chorionic appendages.

Germ line-dependent female sterile.

The dominant female sterile phenotype of Fs(2)1¹ is fully penetrant and expressive. Fs(2)1¹ has no affect on the rate of development or on male fertility. Heterozygous females produce 0-4 eggs per day, which usually collapse after deposition. The dorsal appendages are missing, and the anterior part of the egg is often not covered with chorion. Egg primordia develop normally up to stages 8-10, but then pyknosis of the nurse cell nuclei is seen, chorion defects develop and 90-95% of the egg primordia are resorbed. Heterozygous ovaries transplanted into wild-type hosts show the mutant phenotype, while wild-type ovaries transplanted into heterozygous females develop normally, indicating that the Fs(2)1¹ phenotype is ovary autonomous.