At 18[o]C, less than 30% of the wings of homozygous ap^blt flies display minor abnormalities. Most of them show disruption of the posterior crossvein. At 29[o]C, approximately 70% of the wings show abnormalities, mostly notching of the posterior wing margin and reduced wing size. In many of them, the posterior compartment is severely affected.

Homozygous males have a mating rate 1% of wild type levels, this rate increases with age. If allowed sufficient time with females progeny are produced. For mating success ap^blt is a hypomorph. Homozygous males had equivalent sex appeal as wild type flies. 2 day old hemizygous ap^blt males have a 10--60 fold higher sex appeal than hemizygous ap⁺ males.

Homozygous flies have misshapen and blistered wings and have only 62% female receptivity to mature male ap⁺ flies. The receptivity is lower for flies heterozygous with Df(2R)M41A4. Females are fertile but have a low courtship intensity.

Wings blistered, sometimes inflated and dark due to trapped hemolymph. Mirror-image duplication of posterior wing blade structures occurs (FBrf0004792; FBrf0033471). Wing venation may be disrupted. Portions of posterior wing compartment may be transformed into anterior compartment structures, an effect like that of en. Despite relatively mild adult phenotype, extensive cell death observed, localized to wing pouch of imaginal discs; associated with acid phosphatase and lysosomal activity (FBrf0040733). Clonal analysis revealed nonautonomous expression of phenotype. Heterozygotes with ap⁴ or ap^56f and hemizygotes show blistering phenotype only (FBrf0033471). ap^blt/ap⁷³ⁿ shows transformation phenotype and aldehyde oxidase histochemical staining of these wing discs is consistent with transformation (FBrf0038704). Adults long lived.