线叶山黧豆 xian ye shan li dou

Plants puberulent or glabrous, 10-40 cm tall. Stem usually narrowly winged. Leaves with short, simple tendril at apex; stip­ules linear; leaflets 1- or 2(or 3)-paired, linear, rarely elliptic-lanceolate. Raceme 1- or 2(-4)-flowered.

● Sichuan, Yunnan.

Plants of Lathyrus palustris from the mountains of Sichuan and Yunnan appear as depauperate specimens of the European L. palustris var. palustris, having reduced numbers of leaflets and flowers. This is morphologically consistent with Seringe’s L. palustris var. linearifolius from Denmark and Switzerland, but it is unclear if these are convergent traits or represent a genuine disjunction. Pending molecular evidence, we treat these SW Chinese specimens under L. palustris var. lineari­folius. Specimens of L. quinquenervius are sometimes labeled L. palus­tris var. linearifolius, but L. quinquenervius is a far larger plant with parallel veins in the leaflets and linear, acute stipules with a falcate basal spur.