Blainvillea Cass.

Annual or perennial herbs with taproot; stems erect. Leaves simple, opposite (sometimes becoming alternate above), petiolate, ovate, deltate to lanceolate, crenate to serrate, 3-veined; base cuneate. Capitula terminal, in leafy dichotomous cymes or openly paniculate, radiate or almost disciform; involucral bracts in 2 series; outer bracts ovate to lanceolate, usually herbaceous; inner bracts sometimes scarious; receptacle paleate; paleae scarious, oblong, conduplicate, truncate and laciniate at apex. Ray florets female, fertile; ligule minutely 2-or 3-lobed, yellow or white. Disc florets bisexual, fertile; corolla 5-merous, yellow or white; anther sacs black. Ray achenes 2-or 3-angled, dorsiventrally compressed, smooth to weakly rugose, not winged. Disc achenes obpyramidal to obovoid, 2–4-angled, usually laterally compressed, not winged. Pappus of 0–5 (–8) awns, and/or with a few (usually very short), unequal, shortly connate scales.