Dopatrium

Annual herbs, slender, erect, glabrous, somewhat fleshy, sometimes aquatic, branching mainly at base. Leaves opposite, crowded towards base of stem, becoming smaller, few and distant above, simple, linear-lanceolate, or oblong to ovate, entire, obscurely palmately veined. Flowers solitary in axils of upper leaves, pedicellate, chasmogamous, or sometimes lower flowers sessile to subsessile, cleistogamous; pedicels filiform, ebracteolate. Calyx tubular, 5-lobed to +/- halfway; lobes narrow, obtuse, imbricate. Corolla bilabiate; tube +/- campanulate, mouth wide; upper lip entire or 2-lobed, outside in bud; lower lip very broadly 3-lobed, mid-lobe deeply bifid; all lobes spreading. Stamens 2, posterior, included; filaments short, filiform, arising in upper part of corolla tube; anthers bithecate; thecae equal, parallel, separate, glabrous, held apart by a connective with 2 short arms (slightly stipitate); staminodes 2, anterior, minute or 0. Ovary bilocular, globose or ovoid; ovules many; style filiform, straight, persistent; stigma slightly 2-lobed, somewhat peltate. Fruit a spherical, loculicidal capsule; valves 2, entire or bifid. Seeds small, many, +/- ovate, tuberculate. x = 7.