17. Rhamnus nigricans Handel-Mazzetti, Sitzungsber. Kaiserl. Akad. Wiss., Math.-Naturwiss. Cl., Abt. 1. 62: 234. 1880.
黑背鼠李 hei bei shu li
Shrubs or small trees, dioecious, to 5 m tall, unarmed. Young branches pubescent; branchlets slender, with numerous tuberculate lenticels. Leaves alternate; stipules caducous; petiole 1.2-2 cm, sparsely puberulent; leaf blade turning black when dry, adaxially ± shiny, papery or thickly papery; lower leaf blades smaller, elliptic, oblong, or broadly elliptic, 7-16 × 3.5-7 cm, abaxially puberulent or only on veins, adaxially with small granules, glabrous or subglabrous, lateral veins 6 or 7 pairs, prominent abaxially, impressed adaxially, base rounded, margin slightly revolute, densely cartilaginous serrulate, apex shortly acuminate or caudate. Flowers unisexual, 5-merous, puberulent, in axillary, bracteate, rather short cymose racemes or branched cymose panicles, with minute bracteoles; bracts small, leaflike. Pedicels ca. 1.5 mm, stout, glabrous. Sepals triangular, glabrous. Petals oblong, less than 1/2 as long as sepals. Style of female flowers 3-cleft. Drupe purple-black at maturity, obovoid-globose or globose, with persistent calyx tube at base, with 3 stones. Seeds abaxially with a margined furrow extending over 3/4 of length. Fl. May-Jul, fr. after Jul.
● Mountain slopes with open vegetation; 1500-2800 m. Yunnan.
This species is very similar to Rhamnus napalensis in leaf shape; however, the latter differs in having leaves abaxially usually glabrous, rarely veins and petioles sparsely hairy, inflorescences to 12 cm, and flowers and pedicels glabrous.