Flora of North America species comparison

usually ascending, occasionally erect, often arched at tips, 20–80 cm, sparsely to moderately pilose to villous or with short, incurved hairs, hairs often concentrated at nodes and distally, occasionally in 2 bands along opposite sides of stem.

erect, unbranched or branched, 5–20 cm, glabrous.

opposite;

stipules usually distinct, sometimes connate basally on one side of stem, small scales, irregularly toothed, fringed, or divided, 1–1.5 mm, sparsely to moderately villous distally;

petiole 0.3–1.6 mm, moderately pilose to villous;

blade oblong to oblong-lanceolate, 8–40 × 3–12 mm, base asymmetric, one side usually angled or rounded, other side ± truncate to cordate-auriculate, margins serrulate, apex angled with blunt tip, abaxial surface pale green or faintly to strongly reddish tinged, adaxial surface usually reddish-mottled or with conspicuous reddish spot, both surfaces usually sparsely to moderately pilose, especially toward base, sometimes glabrous; 3–5-veined from base, pinnate distally, veins faint.

petiole absent;

blade obovate, linear-oblong, or spatulate, 2–20 × 2–10 mm, base cuneate or attenuate, margins entire, apex acute, obtuse, emarginate, or mucronate, surfaces glabrous;

venation usually inconspicuous, sometimes 3-nerved from base, midvein prominent.

narrowly obconic, 0.5–1 × 0.3–0.7 mm, glabrous;

glands 4, usually green, sometimes reddish purple, oblong to nearly circular, 0.2–0.4 × 0.3–0.5 mm;

appendages white or pinkish, ovate to broadly elliptic, 0.2–1 × 0.2–1.5 mm, distal margin entire.

cupulate, 0.5–1.2 × 0.6–1.3 mm, glabrous;

glands 4, elliptic to orbiculate, 0.2–0.3 × 0.3–0.8 mm;

horns usually absent, occasionally divergent, 0.5–1.2 mm.

5–28.

6–10.

ovary glabrous;

styles 0.6–2.5 mm, 2-fid 1/2 length.

ovary pilose only at base, styles 0.9–1.1 mm, 2-fid.

ovoid, 1.6–2.3 × 1.5–2.4 mm, glabrous;

columella 1.4–1.6 mm.

subovoid, 2–3 × 1.8–3 mm, slightly lobed;

cocci rounded, smooth, glabrous or slightly pilose along abaxial region;

columella 1.1–1.8 mm.

dark brown, sometimes with thin, white coating (often more persistent along angles than faces), elliptic-ovoid to ovoid, rounded-angular in cross section, 1–1.6 × 0.5–0.8 mm, surface finely and irregularly wrinkled, sometimes faintly so, or with indistinct, shallow, rounded cross ridges.

grayish, whitish, or light brownish, ovoid, 1.2–1.8 × 0.7–1.1 mm, transversally sulcate;

caruncle subglobose to subconic, 0.2–0.5 × 0.2–0.5 mm.

solitary at distal nodes or in small, cymose clusters at branch tips;

peduncle 0.5–2.5 mm.

peduncle 0–2 mm.

arrangement: terminal pleiochasial branches 2–5, each 2–6 times 2-branched;

pleiochasial bracts similar in shape to but usually shorter and wider than distal leaves;

dichasial bracts distinct, widely ovate, rhombic, or suborbiculate, imbricate, base cordate, truncate or cuneate, margins finely denticulate, apex acute or obtuse, strongly mucronate;

axillary cymose branches 0–10.

= 12, 14, 22.