Examples from the Web for setiform
Antennæ short; third joint round; arista apical, slender, setiform.
Setiform: in the form of a bristle or seta: when a slender short bristle arises from a thicker basal joint.Explanation of Terms Used in Entomology|John. B. Smith
Actually there is more than one type of setiform in the hair constellation; they vary in length, width and color.
Antennæ short; third joint round; arista apical, long, slender, setiform.
Attention was not given, however, to every type of setiform.