Each abdominal segment consists mostly of a broad central region of posterior hairy zone (PHZ) cuticle flanked to the anterior and posterior by intersegmental membrane (ISM) in heterozygous flies. Each abdominal segment is mirror symmetric, with the PHZ trichomes in the anterior half of the segment directed anteriorly, and the trichomes in the posterior half of the segment directed posteriorly. Interspersed islands of apparently normal abdominal cuticle with normal polarity are seen. The patches of tergite cuticle are lightly pigmented and do not carry macrochaetae. en^Es/en^Apa transheterozygotes have a similar phenotype, except that no tergite islands are present.

Transheterozygotes with en^Enci have reduced adult viability and wings with vein defects in the posterior compartment.

Partial removal of the darkly pigmented bands at the posterior margins of the abdominal tergites.

Heterozygotes have a partial absence of abdominal markings.

viable