Homozygotes show slow development, molting to third instar one day later than heterozygous siblings. Most die as third instar larvae. Many of the larvae surviving to the third instar remain so for up to eight days and initiate wandering behaviour but never pupariate. 15% of homozygotes do form small pupae, and about two thirds of these survive to eclose as miniature adults with unexpanded wings.

Pka-C1[+]/Pka-C1⁰⁶³⁵³ is an enhancer of decreased body size | pupal stage phenotype of Nf1^E2