A significantly increased fraction of border cell clusters in rk^11P mosaic egg chambers display migration delay relative to controls. The border cells in rk^11P mosaics are properly specified and of the correct number but they often fail to rapidly detach themselves from their epithelial neighbors at the initial stages of migration. Partially mutants border cell clusters fail to cleanly detach themselves from the epithelium more often and display more penetrant delay phenotype than fully mutant clusters, whose behaviour is not significantly different from wild-type clusters. The partially mutant border cell clones also show mislocalization of E-cadherin and apical polarity markers. Neither the detachment phenotype nor the aberrant marker localization is influenced by the presence or absence of rk^11P mutant clones also in the anterior follicle cells of the mosaic egg chambers.

Homozygous embryos that are around the time of hatching look like fully developed first instar larvae, with normal segmentation, tracheal trees, mouth hooks and denticle belts and no obvious defects in the gastrointestinal tract.