Flora of North America species comparison

erect, ascending, or decumbent, unbranched or branched.

simple or few to several from base, erect, ascending, or decumbent, (unbranched or branched distally), 0.5–3.5(–5) dm.

basal and cauline;

petiolate or sessile;

basal rosulate or not, petiolate or sessile, blade margins entire;

cauline petiolate or sessile, blade (base cuneate or attenuate), margins entire.

subsessile or (proximal) shortly petiolate;

blade usually narrowly oblanceolate to linear, sometimes spatulate or obovate, 3–4(–4.5) cm × (0.5–)1–3.5(–5) mm, base attenuate or cuneate, apex obtuse or acute.

(few- to several-flowered, sometimes corymbose or paniculate).

sepals ovate or oblong, lateral pair not saccate;

petals yellow or white [rarely pink], suborbicular, spatulate, oblanceolate, linear-oblanceolate, or, obovate (apex obtuse or emarginate);

stamens tetradynamous;

filaments not winged, uni- or bilaterally winged, appendaged, or toothed;

anthers ovate or oblong;

nectar glands (4), 1 on each side of lateral stamen, median glands absent; (placentation apical or parietal).

sepals (persistent) oblong, (1.5–)2–3 × 0.7–1.1 mm, pubescent as pedicels;

petals (often persistent) white or pale yellow, usually linear to linear-oblanceolate, rarely obovate, 2–3(–4) × 0.3–0.7(–1) mm, apex emarginate, glabrous or sparsely stellate-pubescent abaxially;

filaments (slender) not appendaged, toothed, or winged, 1–1.5 mm;

anthers ovate, 0.15–0.2 mm.

ascending, divaricate, or reflexed, slender or stout.

divaricate or ascending, straight, slender, 2–5(–6) mm, trichomes stellate, with fewer, simple and forked ones.

sessile, ovate-oblong, obovate, or elliptic [obcordate, rarely globose], usually strongly flattened, latiseptate, rarely inflated;

valves each not veined (smooth), pubescent or glabrous;

replum (visible), rounded;

septum complete, (membranous, translucent, veinless);

ovules 1 or 2 [or 4–8] per ovary;

stigma capitate.

orbicular, (2–)3–4(–5) mm diam., apex emarginate or truncate;

valves uniformly inflated at middle, strongly flattened at margins, sparsely stellate-pubescent;

ovules 2 per ovary;

style (slender), 0.3–0.6(–1) mm, basally stellate-pubescent or glabrous.

biseriate or aseriate, flattened, winged or not, orbicular or suborbicular to ovoid;

seed coat (smooth or minutely reticulate), mucilaginous or not when wetted;

cotyledons accumbent or incumbent.

oblong to ovoid, compressed, 1.1–2 × 0.7–1.1 mm, margins narrow, ca. 0.1 mm wide.

= 32.