Laggera 六角草屬
型態特徵
Annual or perennial herbs, erect, branching, glutinous-pubescent to glabrous. Leaves alternate, often rigid, oblong, dentate, base often decurrent. Heads heterogamous, disciform, in racemes on axillary branches, florets yellowish-purple. Outer florets pistillate, in many series, fertile, minute, filiform, 5-lobed. Central florets bisexual, few, fertile, tubular, limb 5-lobed. Involucre campanulate, bracts many seriate, subimbricate, often rigid, outer ones shorter, herbaceous, often recurved. Receptacle flat, naked. Anthers shortly sagittate at base, auricles obtuse or acute, often unequal. Style of central florets bifid. Achenes ellipsoid, 10-ribbed, hirsute. Pappus white, bristles slender, equal, minutely scabrid.
About 17 species in tropical Africa, Arabia and Asia; one species in Taiwan.
