Flora of North America species comparison

ribbed to striate, hispid or glabrous;

prickles infrastipular, paired, also sparse along internodes, recurved.

ribbed, glabrous;

prickles sparse along ribs, recurved.

stipules lanceolate, 7–12 mm, glabrous to sparsely setose;

petiole 1–4.5 cm;

primary rachis 0–2.5 mm;

pinnae 1 or 2 pairs, digitate;

leaflets 15–25 pairs, blades obliquely linear-oblong, 5–10 × 2–2.5 mm, margins setose, 1 eccentric vein prominent abaxially, apex acute to mucronate, surfaces glabrous.

stipules linear or filiform, 2–3.5 mm, glabrous;

petiole (2–)2.5–3(–4) cm;

primary rachis 2.5–3.5 cm;

pinnae 1–3 pairs;

leaflets 9–14 pairs, blades obliquely linear, 3.5–6 × 0.7–1(–1.4) mm, margins ciliate, 1 eccentric vein evident abaxially, apex acute, mucronulate, surfaces glabrous.

95–125-flowered, axillary, globose or subglobose capitula, solitary or fascicles of 2 or 3, also disposed in racemiform branches, 10–15 mm diam.;

bracts linear to lanceolate, 1/2–2/3 corolla length.

35–40-flowered, axillary, globose capitula, solitary, 10–12 mm diam.;

bracts spatulate, 1/4–1/3 corolla length.

1–3 cm.

1–5 cm.

0 mm.

0.2 mm.

bisexual;

calyx campanulate, lobes 4, 1/10 corolla length;

corolla pink, glabrous, lobes 4, 1/4 corolla length;

stamens 4, filaments distinct to base, lilac;

ovary sessile to shortly stipitate, glabrous;

style attenuate at apex;

stigma poriform.

bisexual and staminate;

calyx campanulate, lobes 5, 1/5–1/4 corolla length;

corolla pink, glabrous, lobes 5, 1/4–1/3 corolla length;

stamens 10, filaments connate at bases, pink;

ovary stipitate, glabrous;

style attenuate at apex;

stigma tubular.

sessile, straight, linear-oblong, 10–15 × 3–4 mm, constricted between seeds, valves with 2–5 segments, margin armed, long-setose, apex acuminate, faces glabrous.

sessile, straight, linear-oblong, tetragonal, (45–)70–90(–100) × 4–4.5(–5) mm, not constricted between seeds, valves entire, 1–2.5 mm wide, margin 2.5–3.5 mm wide, prickly or unarmed, apex rostrate, rostrum 5–10 mm, faces glabrous.

2–5, ochre, lenticular, 3–3.2 × 2.5–3 × 1–1.2 mm, testa smooth or porous, fissural line 90%.

(6–)10–16, dark brown, oblong or subrhomboid, 5–6 × 2.5–3 × 1.5 mm, testa porous, fissural line 90%.