Viburnum calvum Rehder; V. schneiderianum Handel-Mazzetti.

Shrubs, evergreen, to 3 m tall. Bark gray-brownish. Branchlets of current year purplish at first, later grayish yellowish, stellate-pubescent or subglabrous; branchlets of previous year gray or gray-brownish, terete, glabrous, with dispersed, small, rounded lenticels. Winter buds ovoid-oblong, with one pair of separate scales; scales reddish brown, ciliate, apex acute. Leaves generally opposite, sometimes in whorls of 3, not clustered at apices of branchlets; stipules absent; petiole green, slender, 6-12 mm, glabrous; leaf blade purplish when young, becoming abaxially pale greenish and adaxially intense green and lustrous, broadly ovate or ovate to ovate-lanceolate or rhombic-elliptic, rarely orbicular, (0.8-)3-6(-10) × 1.5-3(-6.5) cm, leathery, both surfaces glabrous, midvein raised abaxially, lateral veins 5-8-jugate, pinnate, arched, branched, anastomosing near margin, inconspicuous abaxially, impressed adaxially, veinlets transverse, inconspicuous abaxially, slightly impressed adaxially, not lobed, base broadly cuneate, both sides often slightly asymmetric, without glands, margin often remotely irregularly denticulate, rarely entire, apex obtuse, mucronate, rarely acute or emarginate. Flowers appearing after leaves; inflorescence a compound umbel-like cyme, terminal, 2-6 cm in diam.; rays whorled; first node of inflorescence usually with 5-7 rays, lax, glabrous, without large sterile radiant flowers; peduncles 0.6-6 cm; bracts caducous, leaflike, green, linear to linear-lanceolate, glabrous; bracteoles scalelike. Flowers usually on rays of 2nd order, not fragrant; pedicel 2-3 mm. Calyx greenish; tube obconical, ca. 1 mm, glabrous; lobes broadly triangular, broader than long, very small, ca. 0.5 mm, nearly 1/2 as long as calyx tube, glabrous, apex obtuse. Corolla white, rotate, ca. 5 mm in diam., glabrous; tube ca. 1 mm; lobes spreading, ovate-orbicular, ca. 1.5 mm, slightly longer than tube, apex rounded, margin entire. Stamens slightly shorter than corolla, inserted near base of corolla tube; filaments ca. 2 mm; anthers yellow, ovoid, ca. 1 mm. Styles nearly as long as calyx lobes; stigmas subsessile. Fruit not turning red, maturing blue-blackish, ovoid or globose, 5-6 mm, base rounded, apex acute, glabrous; pyrenes globose, ca. 5 mm in diam., with 1 very shallow ventral groove, apex rounded. Fl. Apr-Jun, fr. Jul-Oct.

Two forms may be recognized as follows: the typical form (V. atrocyaneum f. atrocyaneum) has leaves always opposite, leaf blade broadly ovate or ovate to ovate-lanceolate or rhombic-elliptic, whereas V. atrocyaneum f. harryanum (Rehder) P. S. Hsu (Acta Phytotax. Sin. 13(1): 120. 1975; V. harryanum Rehder, Mitt. Deutsch. Dendrol. Ges. 22: 263. 1913; V. atrocyaneum subsp. harryanum (Rehder) P. S. Hsu; V. atrocyaneum var. puberulum (C. K. Schneider) P. S. Hsu; V. calvum Rehder var. kwapiense Handel-Mazzetti; V. calvum var. puberulum C. K. Schneider) has leaves in whorls of 3, leaf blade orbicular.

Forests, scrub; 1000-3200 m. NW Guangxi, Guizhou, Sichuan, SE Xizang, Yunnan [Bhutan, N India, Myanmar, N Thailand].