1. Solitary axillary flowers in all axils, sometimes ending in a terminal raceme not exceeding 5 cm long........................................ 2

- Solitary axillary flowers absent or present only on the two leaves before the inflorescence. Inflorescence a terminal or axillary raceme or panicule, rarely shorter than 5 cm long........................................................................................................................... 4

2. Fruit a lomentum; individual articles triangular.......................................................................................... Adesmia securigerifolia

- Fruit a hemicraspedium; individual articles discoid or spherical..................................................................................................... 3

3. Fruit articles orbicular; stipules 4–6 mm long.................................................................................................. Adesmia bonariensis

- Fruit articles discoid; stipules 2.5–3.5 mm long.................................................................................................... Adesmia smithiae

4. Stoloniferous decumbent and prostrate subshrubs, rarely ascendant, sometimes with adventitious roots from stem branch nodes............................................................................................................................................................................................................. 5

- Ascendant to erect subshrubs or shrubs; never with adventitious roots from stem branch nodes................................................. 13

5. Stems and inflorescence rachis glabrescent to glabrous, glandular trichomes rarely present.......................................................... 6

- Stems and inflorescence rachis pubescent to hirsute or pilose, glandular trichomes commonly abundant..................................... 7

6. Fruits with lenticular articles, laterally flattened; pedicels erect when plant in fruit.............................................. Adesmia bicolor

- Fruits with spherical articles, not laterally flattened; pedicels reflexed when plant in fruit.................................. Adesmia globosa

7. Leaves 10 cm long or longer.................................................................................................................................. Adesmia latifolia

- LeaVes ˂ 10 cm long......................................................................................................................................................................... 8

8. Calyx lobes twice the calyx tube length; calyx equalling the corolla in length............................................................................... 9

- Calyx lobes shorter, equaling or slightly longer than the calyx tube (never twice as long); calyx shorter than the corolla.......... 10

9. Plants glandular trichomes exceeding 1.5 mm in length; seeds with a thin aril............................................. Adesmia subtropicalis

- Plants glandular trichomes shorter than 0.5 mm in length; seeds without an aril................................................. Adesmia miottoae

10. Plant indumentum pilose, with glandular trichomes abundant on stems, leaves, calyces, and fruits................... Adesmia punctata

- Plant indumentum incanous-pubescent, glandular trichomes scarce............................................................................................. 11

11. Fruits muriculate, with adpressed thickened setules on each article.................................................................... Adesmia uruguaya

- Fruits pubescent, with erect setules, never thickened on each article............................................................................................ 12

12. Fruit a lomentum; adventitious roots absent............................................................................................................. Adesmia grisea

- Fruit a hemicraspedium; adventitious roots present................................................................................................. Adesmia incana

13. Leaflets with a lobed margin, rarely only dentate in A. pimpinellifolia......................................................................................... 14

- Leaflets with an entire margin........................................................................................................................................................ 15

14. Leaflets strongly lobed, 1–3 mm wide; central Argentina....................................................................................... Adesmia gilliesii

- Leaflets slightly lobed, 3–8 mm wide; northern Argentina, Bolivia, and Peru........................................... Adesmia pimpinellifolia

15. Leaflets with apex retuse............................................................................................................................... Adesmia riograndensis

- Leaflets with apex truncate, obtuse, acuminate, or acute............................................................................................................... 16

16. Inflorescence a panicule; restricted to the province of Neuquén, Argentina................................................. Adesmia neuquenensis

- Inflorescence a raceme; and sometimes with axillary flowers....................................................................................................... 17

17. Fruits with lenticular articles; restricted to Bolivian and Peruvian highlands....................................................... Adesmia subnuda - Fruits with orbicular or discoid articles; occurring exclusively in the Pampas grasslands and Patagonian steppes...................... 18

18. Flowers> 9 mm long, or if exactly 9 mm then the standard petal strongly reflexed..................................................................... 19

- Flowers ˂ 9 mm long, or if exactlY 9 mm, then the standard petal erect or slightlY reflexed........................................................ 20

19. Flowers> 14 mm long; standard petal slightlY reflexed; fruit articles 2.5–3× 2.5–3 mm................................ Adesmia grandiflora

- Flowers ≤ 14 mm long; standard petal stronglY reflexed; fruit articles 3.5–4× 4–4.5 mm................................. Adesmia retrofracta

20. Fruit a lomentum with 1–5 discoid articles, covered with an incanous-pubescent indumentum..................... Adesmia cordobensis

- Fruit a hemicraspedium with 6–10 spherical muriculate articles......................................................................... Adesmia muricata