小花亚菊 xiao hua ya ju

Chrysanthemum parviflorum Grüning, Repert. Spec. Nov. Regni Veg. 12: 312. 1913; Tanacetum davidii Krascheninnikov; T. parviflorum (Grüning) H. W. Kung.

Subshrubs, 7-25 cm tall. Old branches short, with flowering and sterile stems. Flowering stems unbranched or shortly fascicular inflorescence-branched at apices of branches, sparsely puberulent. Middle leaves petiolate; leaf blade ovate, ca. 2.5 × 2 cm, abaxially pale gray-white, densely pubescent, adaxially green, sparsely pubescent, 2-pinnatisect; primary lateral segments 1- or 2-paired; ultimate segments linear; proximal and distal leaves 3-5-pinnatisect. Synflorescence a terminal clustered flat-topped cyme. Capitula 5-10. Involucres cylindric, 2.5-3 mm in diam.; phyllaries in 4 rows, rigidly herbaceous, scarious margin hyaline, straw-colored, glossy, apex acute, outer ones lanceolate, ca. 1.5 mm, abaxially puberulent, middle and inner ones narrowly elliptic, ca. 3.5 mm, abaxially glabrous. Florets yellow; marginal female florets 4, corolla tubular, ca. 3.5 mm, apex 5-lobed; disk florets many, corolla tubular. Achenes ca. 1.5 mm.

Low mountains, hills; ca. 1400 m. Hebei, Nei Mongol, Shanxi [Mongolia].