XX homozygotes are transformed into intersexes at 29oC. Females carrying vir2f homozygous germ line clones give rise to purely male offspring when mated to homozygous virts males.
XX virts homozygotes develop as sterile intersexes at 29[o]C. The segmentation of the abdomen has features of both sexes. In general, the size and shape of the tergites are more female than male, and the pigmentation of the sixth tergite is more typical of males, covering more than the posterior 50% of the tergite. The sixth and seventh tergites are not fused, and the seventh tergite is reduced to small triangular plates. The sixth and seventh sternites are not fused, and the seventh sternite is smaller and has fewer bristles than in a normal female. The structures of the female genital primordium are poorly developed, the vaginal plates are small and have a reduced number of bristles. The male genital primordium is well developed, with all animals having a male genital arch amd parts of the penis and hypandrium. The anal plates are arranged laterally and have a bead-like form. They are sometimes connected at the dorsal side. The number of bristles is typical of males, but each plate carries a long bristle, which is typical of females. Rudiments of the female-specific ventral anal plate are sometimes found. The internal genitalia generally show a mixture of male and female derivatives. The gonads consistently develop as ovaries. At 25[o]C or below homozygous XX animals show normal female development, but are only weakly fertile, with the number of fertile females decreasing faster with age than for wild-type females. XY animals are unaffected by the mutation.