Buddleja jinsixiaensis R.B.Zhu, sp. nov. (Figs. 1–2)

Similar to B. delavayi, but leaf blade base rounded to obtuse, inflorescences terminal, corolla tube with long hairs inside and stamens inserted slightly below the middle of corolla tube.

Type:— China. Shannxi Provence: Shangnan County, Jinsixia Grand Canyon, Rocky slope in valley, 33°20’24”N, 110°33’5”E, 1253 m, 27 May 2013, R. B. Zhu 0146 (holotype WUK!, isotypes WUK!).

Shrub 1–1.5 m high. Bark of old branches gray, coming off in strips; young twigs subterete, stellatetomentose, soon glabrescent. Stipules reduced to a transverse line. Leaves opposite; petiole 2–6 mm; leaf blade papery, ovate to very narrowly elliptic, 6–12 × 2–4 cm, both surfaces green and glabrous; base rounded to obtuse, apex acuminate, margin serrate; lateral veins 6–16 per side, depressed on upper surface, conspicuous on lower surface; young leaves stellate-tomentose, soon glabrescent. Inflorescences terminal, slightly drooping, paniculate cymes 10–12 × 2–3 cm, rather lax, each cyme bearing 3–11(–17) flowers; peduncle slightly stellate-tomentose; bracts small and linear, 3–6 mm; bracteoles 2, lanceolate, ca. 1 mm. Calyx campanulate, 2–3 mm, glabrous; lobes 4, ca. 0.5 mm, apex rounded. Corolla blue-purple, corolla mouth white; tube 9–11 × 1.5–2 mm, outside glabrous, inside with long hairs except for base; lobes 4, suborbicular, ca. 3 mm, glabrous; stamens inserted slightly below the middle of corolla tube; stamens subsessile; anthers ovate, ca. 1.5 mm; ovary ovoid, ca. 1 mm, stellate-tomentose; style and stigma ca. 1.2 mm; stigma clavate. Capsule ellipsoid, 5–7 × 2–3 mm, stellate-tomentose. Seeds narrowly elliptic, ca. 2 mm, winged all around.

Phenology:—Flowering in May, fruiting in August.

Distribution and habitat:— Buddleja jinsixiaensis is known only from Jinsixia Grand Canyon (ca. 1200 m a.s.l.), China. A total of two plants only was observed. One was found in Quercus forest and the other one on a rocky slope.

Taxonomic relationships:— Buddleja jinsixiaensis is morphologically similar to B. delavayi Gagnepain (1912: 190) in having lax paniculate cymes. However, B. delavayi has leaf blade base cuneate to decurrent, inflorescences terminal and axillary, corolla tube inside with a few scattered glandular hairs, stamens inserted slightly above the middle of corolla tube (Table 1).

Etymology: — Named after the type locality, Jinsixia Grand Canyon.

Other specimen examined (paratype):— China. Shannxi Provence: Shangnan County, Jinsixia Grand Canyon, in Quercus forest, 33°20’30”N, 110°33’6”E, 1219 m, 28 June 2013, R. B. Zhu 0156 (WUK!).