Flora of North America species comparison

erect, sparsely branched, or branched proximally.

erect or trailing, glaucous or not throughout, branched or unbranched, anthocyanic in age, submerged stems sometimes thickened by aerenchymatous spongy tissue.

blades lanceolate-linear to oblong, elliptic, or spatulate, 15–70(–100) × 4–15(–21) mm.

opposite [subopposite or whorled];

sessile;

blade linear, linear-lanceolate, oblong, linear-oblong, lanceolate, elliptic, or spatulate [ovate], base cordate or auriculate [attenuate].

simple cymes, (1–)3–10-flowered mid stem;

peduncle stout, 3 mm.

indeterminate, axillary, simple or compound cymes or solitary flowers [racemes or capitula].

0–1 mm.

sessile, subsessile, or pedicellate, actinomorphic, monostylous [di- or tristylous];

floral tube perigynous, campanulate or urceolate, semiglobose to globose in fruit, often 8–12[–16]-ribbed;

epicalyx segments shorter than or as long as sepals [longer than or absent];

sepals 4–6[–8], to 1/4 floral tube length;

petals caducous [persistent], (0–)4–8, deep rose purple, pale pink, white, or pale lavender, sometimes with rose purple midvein or basal spot, obovate to suborbiculate; nectariferous tissue present at ovary-floral tube junction;

stamens 4–12(–14)[–27];

ovary incompletely (1 or)2–5-locular;

placenta globose [elongate];

style slender and well-exserted or stout and included;

stigma capitate or punctiform.

capsules, walls thin and dry, indehiscent, splitting irregularly at maturity or initially circumscissile then splitting irregularly.

3.5–5.5 mm diam., included to scarcely surpassing sepals, splitting irregularly.

[2–]100+, obovoid to semiglobose, concave-convex, 0.3–0.4 × 0.3–0.5 mm;

cotyledons ± complanate.

tube urceolate, 3–4 mm;

epicalyx segments as long as or slightly longer than sepals;

sepals 4(–6), shallowly deltate, with mucronate apex;

petals 0–4(–6), pale pink to white, 1 × 1 mm;

stamens 4(–8);

anthers yellow;

style stout, included, ca. 0.5 mm;

stigma capitate.

= 48.