Description

Key Characters:

Growth Form: Stout perennial herbs.

Stems: Older stems with a pale, corky layer of secondary growth, usually branched at or slightly beneath the ground, forming clumps to 2.5–5 dm in diameter.

Roots:

Leaves: Leaves simple. Alternate or opposite, clustered along the apical portion of stem. Blades imbricate, decussate, broadly obovate, 40–45 mm long, 20–55 mm wide, upper ones occasionally involucrate around the flowers, succulent, tuft of hairs in the axil. Margins entire. Sessile or subsessile, with a tuft of hairs 1.5–3 mm long in the axil. Stipules 2, connate basally.

Flowers: Flowers in dense headlike clusters at the ends of long leafless internodes 5–13.5 cm long, these rarely with 1–2 leaves, the inflorescence closely subtended by 4 involucrate leaves. Flowers bisexual (perfect), actinomorphic or rarely slightly irregular, sessile. Calyx of 2 sepals; sepals imbricate, persistent, 8–10 mm long, apex rounded. Corolla of 4–6(–8) petals; petals bright lemon yellow, obcordate, 12– 18 mm long, distinct or connate at base, imbricate. Stamens 40–55, in clusters inserted on nectary disk with a dense mat of yellow papillae at base; filaments usually puberulent; anthers dithecal, opening by longitudinal slits. Ovary partly inferior, 2–3(–9)-carpellate, soon becoming 1-celled; ovules numerous, placentation free-central; styles 2–9, branches 5–6.

Fruit: Capsules membranous; ovoid; 8–9 mm long; circumscissile slightly below middle. Seeds dark brown; reniform; 0.7–0.9 mm long; cells of the seed coat with blunt–tipped spines 0.05 mm long; the surface of fresh seeds glistening and somewhat sticky.

Ploidy:

Habitat: Rare in coastal sites; in volcanic tuff; detritus at the base of sea cliffs; and on steep rocky slopes.

Elevation Range: 10–115 m.