Description

Key Characters:

Growth Form: Annual, twining vines, without tendrils.

Stems: Stems slender, usually 10–100 dm long, branched, finely pilose–papillose.

Roots:

Leaves: Leaves simple. Alternate. Blades narrowly or broadly cordate or sagittate, 3–7 cm long, 2.5–5 cm wide. Apex acute or acuminate. Surfaces pilose–papillose along major veins, especially on lower surface. Margins entire. Petioles 1–5 cm long, pilose–papillose. Stipules present as an ocreae, membranous, 3–4.5 mm long, pilose–papillose.

Flowers: Flowers in nodding, 2 to several in axillary clusters or in racemose inflorescences toward the ends of the branches. Flowers bisexual (perfect), actinomorphic. Tepals (4)5(6), usually petaloid, persistent, green, 2–3 mm long, keeled, enlarging up to 3.5 mm long in fruit and closely enclosing the nuts. Stamens 3–9, but usually 5, exserted or included; anthers dithecal, opening by longitudinal slits. Ovary superior, (2)3(4)-carpellate, 1-celled; ovule 1; styles 2–3, distinct or connate basally, deciduous; stigmas capitate or rarely fimbriate, dry.

Fruit: Nuts dull black; trigonous; protruding up to ca. ½ its length from or completely enclosed by the persistent tepals; 3–4 mm long; punctate.

Ploidy: 2n = 20; 40

Habitat: Barren; disturbed ground.

Elevation Range: ca. 2,070 m.