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Body varies around 2 to 2.4mm in length and is mainly brown with antennal segments 3 to 6, the fore tarsi, and the apical half of the fore tibiae yellow. The mid and hind tarsi are yellowish brown, and the wings have a brown spot at the base, and are colourless otherwise. The head is longer than wide and is weakly striate transversely. Ocelli are present and the postocular setae are long and blunt. Antennal segment 3 has 1 inner and 1 outer sense cone, and segment 4 has 2 outer and 2 inner sense cones. Antennal segment 8 is long, slender and doesn't have a pedicel. All major setae on the prothorax are long, and blunt. The metanotum is somewhat hexagonally sculptured and each foretarsi has a small subapical tooth. This tooth is somewhat larger in males (Stannard 1968). The pelta is triangular with basal lobes, and tergites 2 -7 each have 2 pairs of well-developed sigmoidal wing holding setae (Moritz et al 2001). The major posterior setae on abdominal tergite 9 are moderately long with the mid pair blunt and the lateral pair pointed. On males tergite 8 lacks a defined glandular area (Stannard 1968), and on tergite 9, setae B1 is blunt and B2 is acute (Mortiz et al 2001).

Adults of this species over-winter in the leaves at the base of the host plant or on the flower spikes. As the primary host plant (Verbascum thapsus (Common mullein)) is biennial, a colony will remain on a plant for a period of 2 years before migrating to new plants (Bailey 1939). Females lay their eggs on the flowering shoots of the host plant, the adults feed on the stem, and the larvae feed on the sepals of unopened flowers (Moritz et al 2001).