The white or occasionally mauve flowers of Muraltia arachnoidea grow solitary from leaf axils. There are five leaf-like sepals, also hairy and spine-tipped.
The pair of rounded, spreading lateral petals are broader than long, a pleat running across each blade near its centre. The upper halves of the blades are sometimes broader than the lower halves. The third, central petal is smaller, strongly keeled with a crest at its tip. This petal or its keel is sometimes purplish even on white flowering plants; or dull yellowish brown.
Flowering happens from late winter through summer (Bond and Goldblatt, 1984; iNaturalist).