ZZ21 lev-1(x21) tra-3(e2333) isolated by Jim Lewis as EMS-induced levamisole resistant derivative of N2. Found to carry a cryptic tra-3 allele by Jonathan Hodgkin. XX animals are viable hermaphrodites which produce 500 rather than 330 self-progeny; occasionally Egl; no other signs of masculinization.

Levamisole resistant. Unc. tra-3 mutation discovered late. See Hodgkin & Barnes 1991 for genotype details.