2n = 20

2n = 20

n = 10 bivalents

Prostrate annual or perennial; branches to c. 30 cm long, sometimes rooting from lower nodes, essentially glabrous, but sometimes with short arachnoid hairs near the growing tip. Leaves mostly alternate, obovate or narrowly obovate, (6-)10-20 mm long, 2.5-8 mm wide, entire or shallowly serrate, glabrous, resin-dotted on both surfaces, concolorous or slightly paler beneath. Inflorescence a single shortly pedunculate capitulum, usually leaf-opposed; peduncle 0.5-3 mm long. Capitula at anthesis biconvex to hemispherical, 3-5 mm diam.; involucral bracts 1-2-seriate, obovate with ruminate membranous margins, 1-1.5 mm long; receptacle convex; female (outer) florets 40-80, in 2-4 rows, corollas narrowly cylindrical, 0.2-0.4 mm long (including lobes less than 0.1 mm long), green or yellow-green; bisexual (inner) florets 4-14, corollas broadly obconical, 0.5-0.7 mm long (including lobes 0.2-0.3 mm long and wide) often purplish. Fruiting heads breaking up before stems senesce, involucral bracts at fruiting widely spreading to slightly deflexed; fruiting receptacle 1.5-2 mm diam., with a pith layer entirely contained within the dome of the receptacle; cypselas of female and bisexual florets similar, narrowly obovate, 1.2-2.0 mm long, 0.5-0.8 mm wide, obtuse at apex, usually somewhat flattened, 3- or 4-angled in section, each angle with a thickened longitudinal rib, each intervening face membranous with a less prominent rib (sometimes 1 or 2 faces lacking a rib), at least the larger ribs with short ascending to appressed hairs, intervening faces with scattered glandular trichomes; pericarp slightly thickened at and shortly below the apex.