Homozygous Df(3L)iro-DFM1 (containing ara^DFM1 and removing caup) clone cause a series of phenotypes, adding progressively more 'ventral-type' tissue in the following order: dorsal eye overgrowth or ectopic dorsal eyes, overgrowth of ventral type of cuticle (ptilinum and rostral membrane) ectopic antennal pouches, antenna and maxillary palps. The extra head structures are produced autonomously, but the eyes can be composed of both mutant and wild-type ommatidia. The ectopic ventral structures, all grow from the orbital region of the head. The rest of the dorsal head is displaced by the over-grown tissue.

Df(3L)iro-DFM1 and Df(3L)iro-DFM3 cell clones in the notum have indistinguishable phenotypes. Clones of cells homozygous for Df(3L)iro-DFM1 or Df(3L)iro-DFM3 in the notum induced during the first or second larval instar show malformations. Notum is transformed to wing hinge, with sclerites and tegula-like cuticle with characteristic sensory structures. Surrounding wild type cells are recruited into the ectopic structures. Ectopic axillary sclerites were always in mirror image disposition to the regular ones. Malformations in the more central region of the notum caused failure of fusion of the heminota. Clones in the third instar wing disc organize a fold around themselves, similar to the fold found between the notum and wing hinge parts of the regular wing disc.

Deletion causes embryonic or larval lethality. Transheterozygotes with mirr^B1-12 are semi-lethal with rare escapers. Escapers show outheld wings, lack of alulae and deletion of the posterior supraalar bristle and/or anterior postalar bristle.

When homozygous, in wing clones, differentiation of L5 and the alula fail. Dorsal clones remove L5 dorsally, and ventral clones remove L5 ventrally. No other site in the wing showed a requirement for ara-caup. Notum cells lacking ara and caup are inviable.