Glabrous, erect annual. Stems up to c. 80 cm high, usually not branched at base. Lvs alternate, exstipulate, sessile, finely serrate, obovate-oblong, acute, cordate at base, 10-30-(50) mm long. Terminal umbel 2-5-rayed, with usually few to several axillary rays arising below; lvs subtending rays similar to stem lvs; rays usually secondarily branched and then forming compound dichasia; lvs subtending ray-branches and cyathia becoming broader to deltate towards top of infl. Glands suborbicular, entire. Capsule deeply grooved, with prominent tubercles. Seeds smooth, rounded, and slightly flattened, yellow to reddish brown, 1.2-2 mm long.