Annual herbs with alternate, linear or lanceolate, entire leaves with dendroid or stellate hairs. Flowers perfect, solitary in the axils of bracts, in narrow elongate terminal spikes, ebracteolate. Perianth small or weak, hyaline-white, of usually 3, free, segments (0-5); segments mostly toothed or incised-dissected, unequal, the posterior larger and persistent, the 2 anterior very small. Stamens mostly 1-3 (-5); anthers sub-globular to oval, unappendaged. Stigmas 2, on an obsolescent style. Fruit strongly compressed, exceeding the perianth, roundish to oblong-oval, mostly convex on the front, concave or flat on the back, the margin often narrowly winged; seed vertical, embryo ring-like.