Perennial herbs. Hairs eglandular and/or glandular, or 0. Lvs opposite, exstipulate, linear to ovate; cauline lvs connate in pairs or sessile and amplexicaul. Infl. a lax to capitate dichasium; bracts leaflike; epicalyx 0. Calyx bell-shaped or cylindric, 10-veined, 5-toothed; commissures veined, not scarious. Petals 5, white to red or purple, clawed, entire or emarginate or laciniate; coronal scales triangular, paired at base of limb. Stamens 10. Styles 5. Fr. an ovoid or cylindric capsule, dehiscing by 5 entire teeth; carpophore short or long. Seeds reniform, laterally flattened, warty, not winged.

Annual, biennial or perennial herbs. Hairs eglandular and/or glandular or 0. Lvs opposite, exstipulate, linear to ovate to obovate or oblanceolate. Infl. a compact to lax regular or irregular dichasium or raceme-like monochasium or a panicle with a central axis bearing lateral dichasia; bracts leaflike or scarious; epicalyx 0. Fls ☿ or unisexual. Calyx cylindric, ovoid or inflated, 10-, 20- or 30-veined, 5-toothed; commissures veined, not scarious. Petals 5, white to red, clawed; claw often lobed near base of limb; limb entire, emarginate or divided, sometimes 4-lobed; coronal scales variously shaped, paired at base of limb. Stamens 10. Styles 3 or (4)-5-(6 or more). Fr. an ovoid or cylindric capsule dehiscing by twice as many teeth as the styles, or by as many 2-fid teeth; carpophore very short to long. Seeds reniform, warty or ridged; faces flat or hollowed; backs flat or grooved, rarely winged.