L1/L2 larval lethal. Homozygotes die at the first to second instar molt or at second instar. Larvae do not grow and exhibit a segmentally repeated pattern of tanned spots on the ventral cuticle between the fourth and fifth row of setae and sometimes between the first and second row of setae. Tracheae are convoluted.
Larval lethality is polyphasic, and occasionally viable, fertile adults are seen. The progeny of these adults have a variable phenotype ranging from severe sas defects, to normal, fertile flies.
Lethality occurs during embryonic and larval stages.
Grigliatti.