Flora of North America species comparison

prostrate or decumbent and ascending at tips, subterete or with raised lines decurrent from leaf axils, well branched, 10–50(–70) cm, glabrous or, sometimes, minutely strigillose on leaf margins and inflorescence.

erect, 4-angled, rarely 4-winged, sometimes basally terete, 40–280 cm, simple to densely branched, branches often ascending, glabrous.

opposite;

stipules narrowly deltate, 0.05–0.1 × 0.05–0.1 mm;

petiole narrowly winged, 0.1–2.5 cm, blade narrowly to broadly elliptic or ovate-elliptic, 0.5–4.5 × 0.3–2.3 cm, base abruptly attenuate, margins entire and minutely strigillose, apex subacute, surfaces glabrous;

bracts not reduced.

stipules deltate, 0.2–0.3 × 0.15–0.2 mm;

petiole 0.2–2.2 cm, somewhat flattened and continuous with ridges or wings on stem;

blade elliptic to narrowly lanceolate, 2–20 × 0.2–4 cm, base cuneate, margins minutely scabrid, apex acute or acuminate, membranous, surfaces glabrous or sometimes minutely strigillose along abaxial veins;

bracts often reduced.

leafy spikes or racemes, flowers usually paired in leaf axils of prostrate stems;

bracteoles attached at base or to 2.5 mm distal to base of ovary, sublinear, 0.3–1(–1.8) × 0.1–0.8 mm.

leafy spikes, flowers solitary in distal axils;

bracteoles attached at base of ovary or on lower 1/2, without subtending glands, deltate, 0.3–0.5 × 0.2–0.3 mm, apex acute.

sepals ascending, green, ovate-deltate, 1.1–2 × 1–2.1 mm, margins finely serrulate with minute hairs, apex acuminate, sometimes with blunt tip, surfaces glabrous;

petals 0;

filaments translucent, 0.4–0.6 mm, anthers 0.2–0.4 × 0.3–0.6 mm;

pollen shed singly;

ovary oblong, 1.5–3.5 × 1–2 mm, glabrate;

nectary disc elevated 0.15–0.3 mm on ovary apex, green, 1–2 mm diam., 4-lobed, glabrous;

style pale green, 0.3–0.7 mm, glabrous, stigma subglobose or capitate, 0.4–0.6 × 0.2–0.4 mm, not exserted beyond anthers.

sepals ovate or lanceolate, 3–6 × 1–2 mm, apex acute or short-acuminate, surfaces usually glabrous, sometimes strigillose;

petals obovate, 3.5–5 × 2–2.5 mm;

stamens 8 in 2 subequal series, filaments 1.3–1.5 mm, anthers oblong, 0.6–1 × 0.4–0.5 mm;

ovary obconic, 4-angled, 4–10 × 2–4 mm, usually glabrous, rarely strigillose;

nectary disc plane on ovary apex, 3–4 mm diam., 4-lobed, glabrate;

style 0.5–1.5 × 0.5–0.6 mm, stigma globose, 0.8–1 × 1–1.2 mm, not exserted beyond anthers and pollen shed directly on it.

oblong obovoid, 4-angled, (1.6–)2–5 × 1.5–3(–3.5) mm, thin-walled, irregularly dehiscent or dispersing as unit, pedicel 0–0.5 mm.

oblong-linear to squarish-cylindric, 4-angled, 10–22 × 2–4 mm, thin-walled, irregularly dehiscent, subsessile.

yellowish brown, ellipsoid, 0.5–0.7 × 0.3–0.4 mm, surface cells transversely elongate.

elongate-ovoid, 0.3–0.5 × 0.2–0.3 mm, raphevery reduced and inconspicuous.

= 16.

= 16.