Annual, rather slender, pleasingly aromatic. Stems usually branched, erect, 15-80 cm, quadrangular, with few very short retrorse hairs mainly on angles of stem, leafy. Leaves ovate, 25-35 x 15-20 mm, regularly serrate, acute, cuneate, glabrous or with a sparse indumentum of very short eglandular hairs, gland-dotted; petiole on lower leaves c. 15 mm, less above. Inflorescence unbranched to much branched. Verticillasters 5-15, each with 2 often secund flowers. Bracts narrow oblong-elliptic, 2-3 mm, as long as the pedicels. Calyx in flower c. 1.5 mm, soon in fruit expanding to 5-5.5 mm with two lower lobes longer than the campanulate tube and a subentire-truncate shortly 3-toothed upper lip, 10-nerved; indumentum of short pilose hairs, glabrescent, gland dotted; throat villous. Corolla purplish or white marked pink or purple, inconspicuous, soon deciduous, c. 2-2.5 mm, upper and lower lobes weakly differentiated. Stamens 2; thecae divergent. Nutlets brown, almost globose, c. 1.2 x 1.2 mm, with a prominent raised reticulum.

Type: Described from Nepal.

Distribution: Pakistan, Himalayas to China, Japan, Malaysia.

Usually to be found in marshy places or at the edge of ditches. The flowers, from the evidence of herbarium specimens, appear to be cleistogamous, but field observations are needed. In addition to the tiny flowers with 2 stamens, the enlarged fruiting calyces and the globose, raised-reticulate nutlets are characteristic features.