Perennial, glaucous-green, rather fleshy. Stems erect or ascending, crowded, simple or branched, 1–7 in. high, leafy. Leaves decussate, elliptic roundly ovate or subrotund, the broader ones cordate and sessile or floral ones smaller subcordate and subsessile, less than 1/2 in. long; lower internodes longer than the leaves, the upper ones shorter. Flowers solitary in the crowded axils of upper leaves, of a bright rose colour with 2 opposite and lateral linear acute membranous bracts at base of calyx and exceeding its tube; dimorphous according to the comparative length of the stamens and style. Peduncles very short, adnate to the base of the leaves. Calyx campanulate, rose-coloured, 4-fid, not cornuate; lobes deltoid, acute. Petals 4, twice the length of the calyx-tube, obovate, shortly clawed, persistent, not crumpled in the bud. Stamens 4, about length of calyx or much exserted, inserted near base of calyx-tube. Ovary enclosed in calyx-tube, 4-lobed, 4-celled, sessile; style long and tortuous or about length of calyx according as the stamens are short or long; stigma subcapitate. Capsule 4-valved at least at apex, ultimately 1-celled, very shortly-stalked.