Description

Key Characters:

Growth Form: Annual herbs.

Stems: Stems erect, 1.5–6 dm long, young parts and nodes appressed pilose.

Roots:

Leaves: Leaves simple. Opposite. Blades oblong–elliptic to oblong–obovate, 5–15 cm long, 2–6 cm wide. Surfaces moderately pilose. Margins entire. Petioles 1–1.5 cm long, the upper 1–2 sets of leaves sessile. Stipules absent.

Flowers: Flowers in heads or spikes 1.7–2.5 cm in diameter, these solitary or in clusters of 2–4. Bracts ovate, 3–6 mm long, apex acuminate, bracteoles white, pink, or purple, with a conspicuous dorsal crest 7–12 mm long extending throughout, notched at apex, margins serrate. Flowers bisexual (perfect), actinomorphic. Calyx 6–6.5 mm long. Corolla (petals) absent. Stamens 5; filaments connate into a slender tube; anthers monothecal. Ovary superior, 2–3(4)-carpellate, the carpels connate to form a compound, 1-celled ovary; ovule placentation basal, free-central, or rarely apical; stigmas 2.

Fruit: Fruit in indehiscent utricle; usually somewhat flattened; utricles 1.5–2.5mm long. Seeds 1 per fruit; the surface usually lustrous; endosperm essentially absent; reddish brown; 1.5–2 mm long.

Ploidy: 2n = 32; 40–48

Habitat:

Elevation Range: