Herbs 5-20 cm tall; root system unknown; stems blue or white, sometimes deep purple, simple, rarely branched at base. Leaves triangular to narrowly triangular, 2-8 mm long. Inflorescence a dense, 2-6(-10)-flowered cyme, sometimes reduced to 1 flower. Flowers generally 5-merous, fragrant; calyx tubular, 10-25 mm long, tube 8-20 mm long, often split for most of its length along 1 or 2 sides, lobes deltate to narrowly triangular, 1-5 mm long, sinuses obtuse; corolla blue to purplish, often fading to white, trumpet-shaped, 40-80 mm long, tube 30-60 mm long, inner side glabrous, lobes ovate to narrowly ovate, 12-20 mm long; stamens inserted 5-10 mm below throat, filaments to ca. 3 mm long, anthers 2-3 mm long, free, apex rounded; ovary fusiform, ca. 10 mm long, style 10-50 mm long. Capsule fusiform, 15-30 mm long, dehiscence unknown; seeds urceolate to ovoid, 0.3-0.4 mm long.