Flora of North America species comparison

annual, erect, 2–5 m, herbaceous, glabrous;

prickles absent.

perennial, climbing, branching zigzag, terete, 5–9 m × 5–8 mm, woody, glabrous;

prickles numerous, sparse or absent distally, flattened, rigid, stout, to 4 mm.

few, disposed distally or evenly distributed, subequal;

petiole shorter than blade;

tendrils absent or rudimentary;

blade oblong, oblong-ovate, or sometimes oval, 2.5–12 × 1.5–7.5 cm, not glaucous, puberulent abaxially, base rounded to slightly cordate, margins entire, apex broadly rounded to obtuse or abruptly pointed.

evergreen;

petiole 0.5–1.2 cm;

blade green abaxially, drying to brownish green, narrowly ovate to ovate-elliptic, with 3 prominent veins, secondary veins obscure to prominent, 4.5–6(–8.5) × 2–3.5 cm, not glaucous, glabrous or minutely pubescent abaxially, base auriculate, pandurate, or rounded, cuneate at insertion of petiole, margins entire, apex acute to abruptly deflexed point.

1–3, proximalmost axillary to bracts, 5–12-flowered.

3–8, terminal, axillary to leaves, 5–8(–25)-flowered, loose;

peduncle 0.2–1.5 cm.

perianth greenish;

tepals 3–3.5 mm;

anthers shorter than filaments;

ovules (1–)2 per locule.

perianth green;

tepals: staminate 6–8 mm, pistillate 3–4 mm;

ovule 1 per locule;

pedicel 0.2–1 cm.

globose, 8–10 mm diam., glaucous.

purplish maroon, purple, or black, ovoid to flattened, 5–7 mm, glaucous.

;

rhizomes linear or dense masses of potatolike tubers.

= 26.