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.

usually erect or ascending, rarely prostrate, slightly to distinctly winged, wings to 1.8 mm wide, unbranched to densely branched, 5–60 cm, 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.

alternate;

stipules lanceolate-deltate, 0.13–0.15 × 0.1–0.13 mm;

stolons: petiole attenuate, 0.1–0.5 cm, blade broadly elliptic to suborbiculate, 0.2–0.7 × 0.2–0.5 cm;

stems: petiole winged, 0.1–0.5 cm, blade obovate-spatulate or oblanceolate, sometimes narrowly oblanceolate-elliptic, 0.4–1.7 × 0.15–1 cm, base attenuate, margins subentire or often with hydathodal glands forming minute teeth, or minutely papillose-strigillose, apex acute or mucronate, surfaces glabrous;

leaves on side branches much reduced, glabrous;

bracts near apex and on branches 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 or racemes, flowers solitary in axils, usually not crowded;

bracteoles attached at base of ovary, sublinear or narrowly oblong, 0.4–1.2(–1.5) × 0.1–0.4 mm, usually with swollen base.

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 ascending or spreading, pale green to cream adaxially, ovate-deltate, 0.9–2 × 1–1.9 mm, margins minutely papillose-strigillose or entire, apex acuminate, surfaces glabrous;

petals 0;

filaments translucent, 0.4–0.55 mm, anthers 0.1–0.2 × 0.2–0.3 mm;

pollen shed singly;

ovary pale green, obovoid-subglobose, 0.8–1 × 0.8–1.2 mm, glabrate;

nectary disc nearly flat on ovary apex, light green, 0.5–1.2 mm diam., 4-lobed, glabrous;

style light green, 0.3–0.6 mm, glabrous, stigma subcapitate, 0.15–0.3 × 0.05–0.15 mm, not exserted beyond anthers.

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.

obconic, subterete, 1–1.5 × 1.4–1.9 mm, thin-walled, seeds often visible as bumps, dehiscent by apical ring, pedicel 0–0.2 mm.

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

dark reddish brown, oblong-ovoid, 0.5–0.6 × 0.3–0.4 mm, surface cells transversely elongate, glabrous or, sometimes, densely covered by waxy hairs.

= 16.

= 16.