Flora of North America species comparison

narrowly 4-winged or 4-angled.

erect, sparsely branched.

15–55[–87] × 2–10 mm.

opposite to subopposite;

sessile or subsessile [petiolate];

blade lanceolate to linear-lanceolate, base narrowly attenuate.

indeterminate, axillary, leafy racemes.

sessile or subsessile, actinomorphic, monostylous;

floral tube perigynous, campanulate to turbinate;

epicalyx segments equal to or longer than sepals;

sepals (5 or)6, 1/3–1/2 floral tube length;

petals caducous, (5 or)6, bright yellow;

nectary absent;

stamens (10 or)12(–24);

ovary (3 or)4(–6)-locular;

placenta globose;

style slender;

stigma capitate.

capsules, walls thin and dry, dehiscence loculicidal.

globose, 3–4.5 × 3.5–5.5 mm.

0.5–0.8 × 0.2–0.3 mm.

200+, subpyramidal and elongate;

cotyledons ± complanate.

tube 5–9 × 3–4 mm;

epicalyx segments linear-corniform, 2–2.5 mm, apex often in-curved;

sepals 1.5–2 × 1.5 mm;

petals broadly obovate, 5–10(–14) × 3–5 mm.

= 16 (Mexico, Bolivia).