RK1. Thoracic bristles are pale yellow, thin and twisted. PinB/Pin1 has only vestiges of chaetae on the thorax and has soft, watery-appearing cuticle.
Thoracic bristles of PinB/+ flies are pale yellow, thin and twisted (like PinYt/+ flies but more extreme). PinB/Pin1 has only vestiges of chaetae on the thorax; also has soft, watery-appearing cuticle. homozygous lethal.