Plants polymorphic perennial herbs that become woody at the base, 10-70 cm tall; stems 1 to severa; decumbent, ascending, or erect, almost leaflless to leafy. Basal leaves 3-27 cm long, 0.5-9 cm wide, crowded or in a rosette, oblanceolate or obovate to elliptic, bases attenuate, edges sinuate-dentate to runcinate, margins denticulate with stiff, white teeth; stem leaves like basal leaves but smaller, narrower, and with amplexicaul bases. Synflorescences usually with many heads and spreading-erect branches. Heads often clustered at the nodes, with 18-26 florets; involucres 11-16 mm long, usually with 8 inner phyllaries (5-8 in hybrids). Florets: ligules 7.6-10 mm long, moer or less elliptic, bright yellow on the inner (upper) surface, paler on the outer (lower) surface; anthers 2.4-3.7 mm long (excluding appendages); achenes 3-6 mm long, usually black and sharply wrinkled, subtruncate to shortly beaked, inner achenes with 4 main ribs, marginal achenes with 5 main ribs; pappus 6-9 mm long, persistent, of outer plumose hairs and inner bristles.
Launaea petitiana grows in open places on coastal sands, alluvial plains, and rocky slopes and in fallow fields, open bushland and grassland at 0-1700m. It was reported from regions N1-N3, C1, C2, and S2 in the Flora of Somalia.
Launaea petitiana forms a polymorphic complex. It includes diploids, tetraploids, and hexaploids and some populations that suggest hybriization with Launaea taraxifolia.