Herbs perennial, pubescent with glandular hairs. Roots stout, fleshy. Stems short, stout. Leaves densely aggregated distally on stem; leaf blade entire, basal ones scalelike. Inflorescences clusters of 1-3(-6) axillary flowers, pedunculate or sessile. Flowers actinomorphic, 5-merous. Pedicel short. Calyx tubular-campanulate. Corolla funnelform; lobes overlapping in bud, spreading at anthesis, with inflexed margins. Stamens equal, inserted in corolla throat, included; filaments very short; anthers dehiscing longitudinally. Disc ringlike. Ovary 2-locular. Fruiting calyx much inflated, with prominent netted veins, completely enveloping fruit, slightly open at apex. Capsules globose, much smaller than calyx, circumscissile. Seeds reniform, slightly compressed; embryo curved into a ring, subperipheral.