Annual, erect, 15-20 cm, slender herb. Stem filiform, ± circular, glabrous or minutely scabridulous, branches divaricate or simple. Leaves (4-) 6 (-8) in a whorl, narrowly linear, 6-8 x 1-1.5 mm, acute, lower leaves generally broader and ± spathulate and not aristate; upper leaves narrower, setaceous at the lower portion, margin revolute, ± glabrate. Inflorescence axillary and terminal cyme, branches and pedicel capillary, peduncle 10-15 mm long, few-flowered, pedicel 2-6 mm. Flowers yellowish, often with 1-2 linear-filiform bracts. Corolla c. 0.5 mm in diameter, glabrous, lobes oblong, acute or cuspidate, incurved. Ovary less than 1 mm long. Fruit subglobose, 1-1.2 mm in diameter, blackish, covered with long hooked hairs.