Phellodendron chinense var. glabriusculum C. K. Schneid.

Flowering from May to June; fruiting from September to November.

Phellodendron chinense var. glabriusculum is close relative of Phellodendron chinense var. chinense, but differs from the latter in its glabrous or thinly pubescent (vs. rust-colored tomentose) rachis of leaves.

Phellodendron chinense var. glabriusculum is occurring in Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Shaanxi, Sichuan, Yunnan, Zhejiang of China.

Plastid (trnL intron and trnL-F spacer) and nuclear (ITS-1 and ITS-2 rDNA) regions were analyzed to infer the phylogeny and evaluate the classification of Rutaceae subfamilies Rutoideae and Toddalioideae (Poon et al., 2007). Results shown Phellodendron, Tetradium, Toddalia, and Zanthoxylum were resolved as a clade, supporting the proposal for a ‘proto-Rutaceae’ group.

Trees to 15 m tall. Leaves 7-15-foliolate; rachis glabrous or thinly pubescent; leaflet blades ovate-elliptic to oblong-lanceolate, 8-15 cm long, 3.5-6 cm wide, papery, base cuneate to attenuate and oblique, apex mucronate to acuminate. Inflorescences and infructescence ± compact, rachis, branches, and pedicels robust. Fruit subglobose to ellipsoid, 1-1.5 cm in diameter. Seeds 6-7 × 3-5 mm.

The chromosomal number of Phellodendron chinense 2n = 78 (Guerra, 1984).

Growing in open to dense forests; 800-1500 m.