Berberis leptodonta (Gagnepain) Laferrière.

Shrubs, (0.6-)1-2(-3) m tall. Leaves abaxially yellowish green, adaxially dull green, oblong, 15-18 × 10-14 cm, with 8-12 pairs of contiguous or slightly overlapping leaflets, lowest pair 0.5-1.5 cm above base of petiole, abaxially with raised veins, adaxially with slightly impressed midvein, lateral veins indistinct; rachis 1-2.5 mm in diam.; internodes 1-3(-7) cm, decreasing in length upward; lowest leaflets suborbicular to ovate, 0.7-4 × 0.8-1.5 cm, those above lanceolate to narrowly ovate-oblong, (4.5-)7-10(-14) × 1.5-3 cm, base rounded to subcordate, margin finely 35-65(-130)-spinulose-serrulate on each side, apex caudate-acuminate. Inflorescence 5- or 6-fascicled racemes, 6-7 cm; bracts of inflorescence not seen. Pedicel 5-8 mm; floral bracts oblong, ca. 2 mm. Sepals yellow; outer sepals ovate, ca. 2 mm, apically acute; median sepals oblong, ca. 5 mm; inner sepals oblong, ca. 5 mm. Petals oblong, ca. 3 mm, base without glands, apex rounded, entire. Stamens ca. 2 mm, dilated below anthers; anther connective not prolonged, shortly mucronate. Ovary ca. 1.8 mm; ovules unknown; style absent. Berry unknown. Fl. Aug-Sep, fr. unknown.

The combination of very thin leaflets with up to 130 spinulose serrulations on the margins and petals without glands is unique in Mahonia and instantly identifies M. leptodonta.

● Forests, bamboo thickets, weedy slopes; 200-1500 m. Sichuan, Yunnan.