Flora of North America species comparison

prostrate, forming mats, often fistulose, glabrous.

prostrate, decumbent, ascending, erect, or floating, indumentum of simple trichomes.

sessile;

blade narrowly elliptic, elliptic, or oblanceolate, 3.5–7.1 × 0.5–2 cm, herbaceous, apex acute to obtuse, glabrous.

opposite, sessile or petiolate;

blade lanceolate to ovate, ovate-rhombic, or obovate-rhombic, margins entire.

terminal and axillary, pedunculate;

heads white, globose, 1.4–1.7 cm diam.;

bracts not keeled, less than 1/2 as long as tepals.

axillary or terminal, sessile or pedunculate, several-flowered cylindric spikes or globose heads, without immediately subtending leaves;

bracts and bracteoles scarious.

tepals monomorphic, white, lanceolate or oblong, 6 mm, apex acute, glabrous;

stamens 5;

pseudostaminodes ligulate.

bisexual;

tepals 5, distinct;

stamens 3–5;

filaments connate basally into tube or short cup;

pseudostaminodes 5, alternating with stamens;

ovule 1;

style 1, ca. 0.2 mm;

stigma capitate or rarely 2-lobed.

not seen.

1, reddish brown, lenticular or ovoid-oblong.

not seen.

compressed, ovoid or obovoid, indehiscence.