The flowerheads of Crassothonna cylindrica are borne solitary or in a little-branched inflorescence, on long peduncles that emerge from leaf axils. The flowerhead has one row of oblong ray florets and a central disc of many tiny disc florets; both flower types of the heads are bright yellow. Flowerhead diameter is about 1,5 cm.
Only some florets in the outer rings of the disc have opened yet in the flowerhead in picture. Their five pointed lobes spread while the dots representing closed buds in the centre remind of a honeycomb pattern.
Flowering happens in winter and spring. The photo was taken in August (Vlok and Schutte-Vlok, 2010; Bond and Goldblatt, 1984; Manning, 2009).