Description

Key Characters:

Growth Form: Scandent perennial herbs, somewhat woody toward base.

Stems: Stems moderately retrorsely strigose and occasionally also with some spreading hairs, all hairs curved or somewhat crinkly, 0.3–1 mm long.

Roots:

Leaves: Leaves simple. Opposite. Blades narrowly ovate to ovate, 5–15 cm long, (2.6–)3.5–6.5 cm wide. Apex acute. Base cordate to subcordate. Upper surfaces sparsely villous, usually also glandular–dotted; lower surfaces densely glandular–dotted and villous along veins; blades membranous. Margins crenate and ciliate. Petioles (1.5–)2.5–5.6 cm long, densely villous. Stipules absent.

Flowers: Flowers 4–6 per verticillaster, in unbranched, elongate, terminal, bracteate, racemose inflorescences 10–30 cm long, pedicels 1–1.7 mm long, bracts ovate to broadly ovate, 5–15(–18) mm long, lowermost pair larger, 18–30(–45) mm long, bract and pedicel pubescence same as that of leaves and densely glandular–dotted. Calyx narrowly obconical, becoming hemispherical in fruit, 3–3.5 mm long at anthesis, enlarging in fruit, nerves prominent, sparsely short–villous and densely glandular–dotted, usually 5-toothed, the teeth narrowly deltate to subulate, ca. 0.7–0.8 mm long, ciliate, apex acute, splitting longitudinally, usually persistent or sometimes only ventral 1/2 persistent. Corolla bilabiate, white, tube narrowly funnelform, slightly curved, ca. 7–9 mm long, sparsely short–villous, upper lip ca. 2 mm long, lower lip 3-lobed, slightly longer, lateral lobes ovate, slightly asymmetrical, lower lobe broadly ovate to suborbicular, slightly folded to form a groove, margins somewhat undulate, apex emarginate or entire; nectary disk often present at base of ovary, annular or developed on anterior side only. Stamens 4, both pairs of similar length or upper pair slightly longer, ascending the upper corolla lip, included, aligned with the sinuses; filaments inserted near throat, usually pubescent; anthers dithecal, opening by longitudinal slits; anther sacs divaricate. Ovary superior, 2-carpellate; ovules 1 per ovary lobe, placentation basal-axile; style 1, included, arising between lobes, shortly 2-lobed, the lobes clavate; stigmatic only at apex, 1 lobe often rudimentary; stigmas 2.

Fruit: Nutlets 1.7–2.5 mm long. Seeds with endosperm absent or scanty and oily.

Ploidy:

Habitat: Apparently rare in wet forest; Maui.

Elevation Range: 1,300–1,830 m.