abnormal neurophysiology
lethal
lethal - all die before end of pupal stage
lethal - all die before end of pupal stage | recessive
some die during pupal stage
ERG defect, slow return of the potential to base light at light off.
biD2 has lethal - all die before end of pupal stage | recessive phenotype, suppressible by Dp(1;3)DC116/+
Dp(1;3)DC116/+, biD2 has viable phenotype