Wahlenbergia gymnoclada

Rhizomatous perennial; stems simple or occasionally 1- or 2-branched, glabrous or shortly hirsute near base, erect, (10–)20–60 cm high, usually leafless in upper half; leaves opposite near base, becoming alternate, narrowly obovate to linear, 5–50 mm long, 1–2(–3.5) mm wide; margins thickened, usually with a few, distant callus-teeth. Hypanthium obconical, 2.5–4 mm long, glabrous; calyx-lobes erect, narrow-triangular, 2–6 mm long, glabrous; corolla campanulate, blue, sometimes yellowish outside, tube 3–6 mm long, shorter to longer than calyx-lobes, lobes elliptic, 7–16 mm long, 4–7 mm wide, acute, widely spreading; style 6–11 mm long, hardly constricted, lobes 3, oblong. Capsule obconical to narrowly obconical, 5–9 mm long, 2–4 mm wide. Flowers Oct.–Dec.