Herbs [herbaceous vines, or low shrubs], caulescent [stemless], from rhizomes [tuberous roots]. Leaves simple, stipules absent. Basal leaves sheathing. Cauline leaves present [absent], alternate [whorled], petiolate, venation ± palmate [arcuate-pinnate with strongly developed midvein], transverse parallel veinlets connecting primary veins. Inflorescences axillary, cymose [racemose or unifloral]. Flowers bisexual, radially [bilaterally] symmetric; perianth hypogynous [to epigynous]; tepals 4[-5], distinct [connate]; stamens 4[-5], opposite tepals; ovary 1-locular; placentation apical [basal]; style 1 [absent]; stigmas [1]-3. Fruits capsular, 2[-3]-valved. Seeds globose [to ellipsoid].