4. Senecio densiserratus C. C. Chang, Bull. Fan Mem. Inst. Biol., Bot. 6: 56. 1935.
密齿千里光 mi chi qian li guang
Herbs, perennial, rhizomatous. Stem solitary, erect, 70-120 cm tall, simple below synflorescence, sparsely arachnoid-tomentose, glabrescent. Basal and lower stem leaves withered by anthesis; median stem leaves numerous, shortly petiolate; blade adaxially green, narrowly lanceolate or linear-lanceolate, 7-16 × 1-2 cm, papery, abaxially white tomentose except for midvein, adaxially adpressed pubescent, pinnately veined, lateral veins 18-22, obscure, base cuneately attenuate into petiole, margin densely denticulate, apex acute-acuminate-attenuate. Upper leaves smaller; uppermost leaves linear, small. Capitula radiate, numerous, arranged in terminal and upper axillary compound corymbs; peduncles 3-5 mm, slender, densely puberulent, with 2 or 3 filiform bracteoles. Involucres cylindric-campanulate, ca. 5 × 1.5-2.5 mm, calyculate; bracts of calyculus ca. 3, filiform, 1-2 mm; phyllaries 8, linear, ca. 5 × 0.5-0.8 mm, herbaceous, pubescent, margin narrowly scarious, apically acute, puberulent and sometimes purplish. Ray florets 5; corolla tube ca. 3 mm; lamina oblong, ca. 4 × 0.7 mm, 4-veined, 3-denticulate. Disk florets 7-9; corolla yellow, ca. 6 mm, with ca. 3 mm tube and funnelform limb; lobes ovate-triangular, ca. 1 mm, apically acute, papillose. Anthers ca. 1.5 mm, basally shortly obtuse-auriculate, appendages ovate-lanceolate, apically obtuse; antheropodia rather elongate, somewhat dilated in lower half. Style branches ca. 1 mm. Achenes cylindric, ca. 3 mm, glabrous. Pappus white, ca. 5 mm. Fl. Aug-Sep.
● Upland valleys; 2400-3000 m. Gansu, ?Shaanxi, Sichuan (Guanxian, Heishui).