Latin ligula — little tongue, an allusion to the tongue-shaped ray florets.
Perennial herbs, glabrous to hairy. Stems erect, simple or branched. Leaves basal and along stems, alternate, margins toothed, sheathing at base of petiole. Capitula radiate or rarely diskoid, terminal, few to many in corymbs or racemes, often nodding, with stalks. Involucral bracts in 1 row, overlapping, unequal, sometimes joined. Receptacle flat. Ray florets female, usually ligulate, yellow to orange. Disk florets bisexual, tubular, yellow. Achenes cylindrical, glabrous. Pappus of fine bristles.
Petioles with sheathing bases; involucral bracts of 2 types.
About 125 species from Europe and Asia.
Dress (1962).
Source: (2002). Dahlia. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.