Description from Flora of China
Syringa tetanoloba C. K. Schneider; S. tigerstedtii Harry Smith.
Shrubs 2.5-4 m. Branchlets 4-angled, glabrous. Petiole 0.5-2 cm, glabrous or pilose; leaf blade ovate, ovate-elliptic, to lanceolate, 1.5-4(-8) × 1-3(-5) cm, adaxially shining and glabrous, abaxially barbate along veins or glabrous, base cuneate to subrounded, margin tinged with purplish red when young, apex acute to acuminate. Panicles erect, terminal or lateral, 7-25 × 3-15 cm; rachis generally 4-angled, including pedicel and calyx purple-brown, puberulent or glabrous. Pedicel 0-2 mm. Calyx 1.5-2 mm. Corolla pink, lilac, to white, 0.9-2 cm; tube slender, subcylindric, 0.6-1.5 cm; lobes ovate-oblong to lanceolate, spreading. Anthers yellow, inserted below or near mouth of corolla tube. Capsule long elliptic, 1.5-2 cm, smooth. Fl. May-Jun, fr. Sep-Oct. 2n = 46, 48.
The combination Syringa tomentella subsp. sweginzowii (Koehne & Lingelsheim) Jin Y. Chen & D. Y. Hong (Novon 18: 317. 2008) was made after publication of the family treatment for the Flora of China.
* Thickets, woods, near riversides or gullies; 2000-4000 m. W Sichuan