Description from Flora of China
Phlogacanthus paniculatus (T. Anderson) J. B. Imlay.
Shrubs to 2 m tall. Stems 4-angled, glabrous; young branches winged. Petiole 1-1.5 cm; leaf blade oblong to oblong-lanceolate, 10-12 × 2.5-4 cm, abaxially pubescent along veins, adaxially glabrous, base attenuate and decurrent onto petiole, margin undulate to crenulate, apex acuminate. Thyrses terminal, to 18 cm, many flowered; rachis densely villous with gland-tipped trichomes; bracts oblong-lanceolate, shorter than calyx, gland-tipped pubescent, caducous; bracteoles similar to bracts. Pedicel 2-4 mm, gland-tipped pubescent. Calyx 1.2-1.4 cm, gland-tipped pubescent; lobes lanceolate. Corolla light purple, 2-2.4 cm, ventricose, outside gland-tipped pubescent, inside glabrous; lower lip with lobes orbicular, subequal, patent. Stamens included; filaments barbate; anther thecae ca. 1 mm, connective barbate; staminodes very small. Ovary pubescent, with 4 ovules per locule; style 1.6-2 cm, glabrous; stigma slightly 2-cleft. Capsule grayish brown, clavate, ca. 2.3 cm, pubescent, 8-seeded. Seeds ovate in outline, ca. 3.5 × 3.5 mm.
Forests; 300-2100 m. Yunnan [Myanmar].