风箱树 feng xiang shu

Nauclea tetrandra Roxburgh, Fl. Ind. 2: 125. 1824; Cephalanthus glabrifolius Hayata; C. naucleoides Candolle; C. ratoensis Hayata.

Deciduous shrubs or small trees, 1-5 m tall; branches subangled to terete, densely pilosulous or tomentulose to usually glabrous. Leaves opposite or in whorls of 3-5, with number often irregular on a stem; petiole 5-10 mm, densely tomentulose or pilosulous to usually glabrous; blade drying stiffly papery to subleathery, ovate to ovate-lanceolate, elliptic, or elliptic-oblong, 6.5-15 × 3-6 cm, adaxially glabrous to sparsely puberulent and often rugulose, abaxially densely pilosulous to usually glabrous, base obtuse, rounded, or subcordate, apex acute to acuminate; secondary veins 8-12 pairs, often with pilosulous domatia in axils or along costa; stipules persistent or often deciduous leaving a persistent truncate basal portion, broadly ovate, 3-5 mm, adaxially enclosing a ring of persistent white trichomes 0.5-1 mm, abaxially glabrous to occasionally densely pilosulous, apex cuspidate, often with a black terminal gland. Inflorescence densely tomentulose or pilosulous to usually glabrous; peduncles 2.5-6 cm; flowering heads 1-10, 8-12 mm in diam. across calyces, 20-25 mm in diam. across corollas; bracteoles linear-clavate, ca. 2 mm, strigose. Calyx with ovary portion obconic, ca. 1 mm, glabrous, surrounded at base by ring of pilose trichomes; limb with tubular portion 1-2 mm, glabrous to sparsely puberulent; lobes spatulate-oblong, 1-2 mm, densely puberulent, obtuse to rounded, in sinuses usually with stipitate or sessile black gland. Corolla outside glabrous; tube 7-12 mm, pubescent inside; lobes spatulate-oblong, 1-2 mm, obtuse or rounded, in sinuses often with stipitate black gland. Stigma ellipsoid or clavate, ca. 0.5 mm, exserted by 4-6 mm. Fruiting head 10-20 mm in diam. Mericarps 4-6 mm, glabrous; seeds brown, 3-5 mm. Fl. Jun-Sep, fr. Jul-Sep.

Shady sites at roadsides or streamsides; sea level to 700 m. Fujian, Guangdong, Guangxi, Hainan, Hunan, Jiangxi, Taiwan, Yunnan, Zhejiang [Bangladesh, India, Laos, Myanmar, Thailand, Vietnam].

This species was long considered conspecific with Cephalanthus occidentalis Linnaeus of North America; consequently, that name has been frequently but erroneous used for the Asian plants. Ridsdale (Blumea 23: 177-188. 1976) concluded that only one species of Cephalanthus is found in Asia and it is distinct from the North American species. Ridsdale (loc. cit.: 180-181) reported that this species is tolerant of wet soils and sometimes cultivated for ground stabilization.