Herbs, annual, viscid pubescent to nearly glabrous, from slender or stout and ± woody taproots. Stems decumbent to semierect, unarmed, without glutinous bands on internodes. Leaves petiolate, unequal in size in each pair; blade ± thick and succulent, base usually asymmetric. Inflorescences axillary, pedunculate, capitate clusters; receptacle flat to somewhat rounded-conic, with short, pedicel-like projections; flowers maturing from one side of inflorescence to other; bracts persistent, not accrescent, 5-10, distinct, thin and translucent, forming an involucre, linear-lanceolate to ovate, broad. Flowers bisexual, chasmogamous; perianth radially symmetric, funnelform or salverform, constricted beyond ovary, abruptly expanded to 4-5-lobed limb; stamens (3-)4-5, included; styles included; stigmas linear. Fruits fusiform, indurate throughout, or spongy on exterior, minutely puberulent or glabrous; wings 2-4, translucent, prominently veined, scarious, extending beyond apex and/or base of body; sulci smooth or coarsely rugose.