Herbs annual.
Stems usually covered with stiff, erect hairs, often with raised bases.
Leaves basal and cauline, surfaces usually covered with stiff, erect hairs, often with raised bases; sessile or short-petiolate below.
Inflorescences terminal, elongate, spike-like cymes, coiled at tips.
Flowers receptacles conic or elongate; calyx lobes without basal teeth in fruit; corollas bright yellow to orange, tubes cylindric, generally not constricted, appendages in throat generally lacking, limbs spreading.
Fruits erect, adaxially keeled distal to scar, attachment scars lateral and raised, lacking a thick rim, tubercles present or not, sharp or not.
North America, South America. 15 species; 5 species treated in Flora.