adult abdominal sensillum & sternite
adult head & macrochaeta
adult thorax & macrochaeta
Heterozygotes lack one or both postvertical bristles and often lack the upper humeral bristles. Other bristles are rarely affected. Wing vein L5 and sometimes L4 are shortened (as in a normal H allele). Homozygotes have 20% viability under optimal conditions. The head and thorax is almost entirely bald. There is a reduction of bristles on the legs, which is greatest in the proximal segments. Abdominal bristles are present only on the sides and sternites, on which they are reduced to about 5 in number. Wing veins L2, L4 and L5 are much reduced. The wings are often warped.