D.melanogaster/D.mauritiana hybrid females carrying Dp(1;2)v+75d and derived from a cross of D.mauritiana females to D.melanogaster males do not survive. D.melanogaster/D.mauritiana hybrid males carrying Dp(1;2)v+75d and derived from a cross of D.mauritiana females to D.melanogaster males are viable, although they do suffer some decreased fitness. D.melanogaster/D.simulans hybrid males carrying Dp(1;2)v+75d and derived from a cross of D.simulans females to D.melanogaster males are viable, although they do suffer some decreased fitness. D.melanogaster/D.mauritiana hybrid males carrying Dp(1;2)v+75d and derived from a cross of D.melanogaster attached-X females to D.mauritiana males show reduced viability compared to control hybrid brothers that do not carry Dp(1;2)v+75d, and dead late larvae and pupae are common. D.melanogaster/D.simulans hybrid males carrying Dp(1;2)v+75d and derived from a cross of D.melanogaster attached-X females to D.simulans males show reduced viability compared to control hybrid brothers that do not carry Dp(1;2)v+75d, and dead late larvae and pupae are common.