Homozygotes have a vgs wing phenotype. Postscutellars and halteres have an intermediate phenotype. vg81a-s/vg83b27 transheterozygotes have wild-type wings, halteres and postscutellars.
homozygous wing phenotype like that of vgs2 halteres present (more or less) postscutellar bristles present (more or less) homozygous viable female-fertile?