The S-band extends obliquely from the base of cell cu1 across r-m, reaching the anterior wing margin in cell r1, then following the anterior margin to the wing apex. The basal part in cell cu1 and the distal part on the margin of the radial cells are almost always present, but the middle section is sometimes interrupted or absent. The basal part sometimes has a posterior extension to or almost to the posterior wing margin in cell a1.