Flies are smaller than normal with a narrow abdomen. The reduction in size is occasionally longitudinally asymmetrical, either for the whole body or thorax or abdomen separately. Male viability is very reduced and flies rarely live for more than 48 hours after eclosion. Males are sterile, probably due to the reduced viability.

Fly small with narrow abdomen. Reduction in size may be bilaterally asymmetrical and may affect abdomen and thorax independently. Male viability reduced; flies rarely survive more than 48 hr. Sterile, probably owing to reduced vigor. RK3.