The mesonotum, costa and alula are normal in heterozygotes. Distally the wing blade is reduced to two-thirds its normal length. The triple row bristles are replaced by 2-3 rows of unevenly sized bristles, resembling those normally found on the medial and distal costa. In approximately 10% of wings, a bristle in this region may be bracted (indicating a proximal transformation). The posterior row hairs are absent, except immediately distal to the alula, where the hairs are present but are intermediate in size between those of the normal alula and the posterior row (indicating a weak proximal transformation). All bristles of the wing blade have normal polarity. The trichomes are not orientated normally, but are present in whorls. Wing venation is disrupted in heterozygotes, especially in more proximal regions. The proximal region of the wing blade is more pigmented than in the same region of wild-type wings. Normal venation and bristle elements are always seen at the distal tip of the wing blade. The metanotum, scabellum and pedicellum are morphologically normal in heterozygotes. The capitellum is covered in small adventitious bristles and sometimes pedicellar-like sensilla. The pleura, coxa, trochanter, femur and tibia are normal in heterozygotes. The tarsal region is reduced in length; the reduction is restricted to the basitarsus and 2nd, 3rd and 4th tarsal segments, the 5th tarsal segment and claw are unaffected. Tarsal segments 2-4 show varying degrees of fusion, in extreme cases one long segment is formed instead of 3 segments. 70-90% of heterozygotes have an ectopic sex comb on the second tarsal segment of the foreleg (suggesting the metatarsus is transformed into basitarsus). Antennal segments I to III, the arista and the head capsule are normal in heterozygotes. The basal cylinder of the antenna is missing or reduced in size. In place of the basal cylinder, new bristle elements differentiate at the junction of the 3rd antennal segment and the arista, which resemble bristles found on the 3rd antennal segment. Only 5-7 rows of pseudotrachea develop in the proboscis of heterozygotes, in contrast to the 12 rows seen in wild-type flies, the vacant lateral regions being replaced by bristles resembling those normally seen on the labellar cap. Other labial disc derivatives are normal. The phenotype in heterozygotes is consistent with the distal parts of appendages being replaced by pattern elements typically found in more proximal regions of the same disc. The phenotype shows complete penetrance and good expressivity. The distal parts of all appendages are considerably smaller in homozygous In(3R)rn^Dipr flies (which are homozygous for Dipr¹ and rn^Dipr) than in heterozygous Dipr¹ flies. In the wing, the distal and proximal parts of the wing are affected.