Astragalus sect. Skythropos in Flora of China @ efloras.org

12. Astragalus sect. Skythropos N. D. Simpson, Notes Roy. Bot. Gard. Edinburgh. 8: 255. 1915.

肾形子组 shen xing zi zu

Plants perennial, with basifixed white or dark brown to black hairs. Stems 2-10(-20) cm, rarely plants acaulescent. Leaves imparipinnate, with a distinct petiole; stipules free from petiole, lower ones sometimes shortly vaginate-connate behind stem, often scalelike and without leaves in basal parts of stems; leaflets in 4-17 pairs. Racemes with a rather long peduncle, 1-25-flowered. Bracteoles mostly absent. Petals yellow or violet. Stigma glabrous or hairy. Legumes stipitate, 1-locular.

Seven species: Bhutan, China, India, Nepal; six species (four endemic) in China.

1 Petals yellow (2)

+ Petals violet (4)

2 (1) Leaflets in 4-6 pairs. 69 A. nanfengensis

+ Leaflets in (5-)8-15 pairs (3)

3 (2) Plants mostly acaulescent, stems if present up to 1 cm; leaflets on both surfaces loosely to rather densely covered with subappressed white hairs up to 0.7 mm; bracts 3-4 mm; calyx 8-9 mm, with teeth 3-4 mm. 66 A. datunensis

+ Plants with stems 1-10 cm; leaflets adaxially sparsely to loosely hairy or glabrous, rarely densely hairy on both surfaces; bracts 4-10 mm; calyx 8-14.5 mm, with teeth 4-7.5 mm. 71 A. yunnanensis

4 (1) Leaflets adaxially glabrous, abaxially sparsely hairy only at midvein and margins; calyx not violet suffused or red-brown. 70 A. skythropos

+ Leaflets adaxially hairy, if sometimes glabrous, then loosely to rather densely hairy abaxially; calyx violet suffused to red-brown (5)

5 (4) Stipules sparsely to loosely hairy, connate behind stem and sometimes before petiole, rarely free from each other; calyx 9-12.5 mm, strongly violet suffused to red-brown, teeth 4-7 mm; standard 16-26 mm; stigma glabrous. 67 A. kongrensis

+ Stipules only ciliate, all free from each other; calyx 7-9 mm, slightly violet suffused, teeth 2.5-4 mm; standard 13-16.5 mm; stigma hairy. 68 A. licentianus