Description

Key Characters:

Growth Form: Scandent shrubs or lianas.

Stems: Stems usually decumbent or supported by trees in forested areas, sometimes sprawling to sub–erect in open areas or at high elevations, (8–)20–200 dm long, glabrous.

Roots: Taprooted.

Leaves: Leaves simple. Alternate. Blades oblong–ovate to occasionally deltate, sometimes narrowly oblong–ovate or in open sites smaller and ovate–elliptic, flat, 6–22(–30) cm long, (1.8–)2.5–10(–11.6) cm wide; blades not especially thick (occasionally somewhat thickened in open areas or at high elevations on east maui and mauna kea, hawaiʻi), dull. Apex acute, acuminate, or occasionally broadly obtuse. Base truncate or cordate, occasionally broadly cuneate in smaller leaves in open habitats or at high elevations. Surfaces glabrous or sometimes sparsely short–papillose–pilose. Margins entire, rarely slightly undulate. Petioles 1–7 cm long, glabrous to sparsely pilose. Stipules forming sheath or ocrea.

Flowers: Flowers in occasionally (hawaiʻi) pilose in the inflorescence, numerous in large, red or rarely green and sometimes tinged red, diffuse to somewhat congested, many-branched, usually pendent, paniculate inflorescences (15–)25–80 cm or more long, usually 20–30 cm or more wide, rarely narrower. Flowers unisexual (and the plants monoecious), the proportions of each sex varying from nearly equal to one type strongly dominating, actinomorphic. Tepals 6, outer 3 much smaller than inner ones, green, connate at base into a minute floral tube, inner 3 valves erect; staminate flowers with outer Tepals 1–1.2 mm long, the valves reddish or sometimes greenish, membranous, 1.5–1.8 mm long; pistillate flowers with outer Tepals usually reddish, ca. 1–1.4 mm long, the valves reddish or sometimes yellowish green, membranous, ca. 1.5 mm long, enlarging to 4–5 mm long and becoming cordate in fruit, venation becoming conspicuous, margins denticulate, the faces without tubercles. Stamens 6, staminate flowers with anthers ca. 1–1.2 mm long; anthers dithecal, opening by longitudinal slits. Ovary superior, 1-celled; ovule 1; styles 3; stigmas fimbriate, dry.

Fruit: Nuts trigonous; enclosed by the valves; pale brown; ca. 1.8–2.3 mm long; the 2 sides of a single arm of a mature nut distinctly diverging; the angle ca. 45°; margins of arms with a conspicuous rim. Seeds with well-developed; starchy and oily endosperm.

Ploidy: 2n = 54; ca. 56; 60

Habitat: Mesic to wet forest and subalpine woodland.

Elevation Range: (3–)660–3,050 m.