Synedrella Gaertn.

Annual herbs with tap root; stems erect to ascending. Leaves simple, opposite, petiolate, ovate to elliptic, becoming lanceolate in inflorescence, crenate to serrate, 3-veined; base attenuate. Capitula in small, sessile or subsessile, axillary clusters, sometimes solitary on peduncles to 25 mm long, radiate; involucral bracts in 2 series, with outermost 2 or 3 bracts oblong-lanceolate, herbaceous and inner bracts scarious; receptacle paleate; paleae narrow, ± flat, rounded or erose at tip, absent from central florets. Ray florets female and fertile; ligule 2-or 3-lobed, yellow. Disc florets bisexual, fertile; corolla 4-merous, yellow; anther sacs brown to black. Ray achenes flattened, slightly concavo-convex, smooth apart from central longitudinal rib, with conspicuous broad, pale, lacerate, connate wing or thickened margin that apically becomes a flattened pair of pappus awns. Disc achenes clavate, wingless, tuberculate, with pappus of 2 or 3 divergent awns.