Annual herb. Lvs alternate, entire to coarsely serrate. Capitula 1-numerous, solitary. Involucral bracts dimorphic, the outer in 1-2 rows, imbricate and herbaceous, the inner in 1-2 rows and completely membranous. Receptacle slightly convex; scales 0. Outer florets ♀, ligulate, many to numerous in 1 row (more in cvs); ligules white to red, blue or purple. Inner florets ☿, tubular (ligulate in double cvs), numerous. Achenes all similar, obovoid, compressed, hairy, with 2-4 narrow ribs; pappus of 1 row of long scabrid hairs and an outer row of very short hairs.