Description

Key Characters:

Growth Form: Shrubs.

Stems: Stems usually stiffly erect, 7–10 dm long, glabrous.

Roots: Taprooted.

Leaves: Leaves simple. Alternate. Blades flat, ovate to oblong–ovate or oblong–elliptic, 5.5–9(–13.5) cm long, 1.4–5.8 cm wide. Apex acute to obtuse. Base broadly cuneate. Surfaces glabrous, blades thick and somewhat glossy. Margins entire, flat. Petioles 1.7–3.5(–5) cm long. Stipules forming sheath or ocrea.

Flowers: Flowers numerous, in small to medium-sized, green or yellowish green, somewhat congested, many-branched, usually erect, paniculate inflorescences 10–20 cm long, 5–10(–15) cm wide. Flowers unisexual (and the plants monoecious), the proportions of each sex varying from nearly equal to one strongly dominating, actinomorphic. Tepals 6, outer 3 much smaller than inner ones, connate at base into a minute floral tube, inner 3 valves erect, staminate flowers with outer Tepals ca. 1 mm long, the valves membranous, greenish, ca. 1.8–2 mm long, anthers ca. 1.2 mm long; pistillate flowers with outer Tepals greenish, ca. 1–1.5 mm long, the valves membranous, greenish to yellowish green, ca. 1.5–2 mm long, enlarging to 5.5–6.2 mm long and becoming cordate in fruit, the venation becoming conspicuous, margins denticulate, the faces without tubercles. Stamens 6; 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 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 = 60

Habitat: Dry ʻaʻā and pāhoehoe lava and perhaps ash.

Elevation Range: 460–1,300 m.