1. Leaves (sometimes only upper leaves) with geniculate rachis..........................................................................................................2.

- Rachis not geniculate.........................................................................................................................................................................4.

2. Stems hollow; upper stem leaves with more than 4 pairs of leaflets; bracteoles absent or solitary; fruits drooping, separating into mericarps from upper part........................................................................................................................ Elwendia chaerophylloides

- Stems solid; upper stem leaves with 1–4 pairs of leaflets; bracteoles 2–8; fruits erect, separating into mericarps from the base.................................................................................................................................................................................................................3.

3. Uppermost stem leaves with short triangular sheaths and more or less numerous bundle-shaped segments; bracteoles 2–4(5); styles 0.8–1 mm long...................................................................................................................................................... Elwendia lindbergii

- Uppermost stem leaves with narrow sheaths 2.5–4 cm long, pinnatisect with several segments; bracteoles 5–8; styles 1.2–1.6 mm long................................................................................................................................................................ Elwendia seravschanica

4. Styles erect, slightly spreading or hooked; not appressed to stylopods............................................................................................5.

- Styles recurved and usually appressed to stylopods..........................................................................................................................8.

5. Uppermost stem leaves with segments up to 4 cm long; bracteoles 5–8; styles up to 2 mm long........................... Elwendia capusii

- Uppermost stem leaves with segments up to 1.5 cm long; bracteoles absent or 1–3; styles about 1.3 mm long.............................6.

6. Terminal segments of radical leaves 1–2 mm long; bracteoles absent or rarely 1–3; petals with several secretory ducts; styles erect..................................................................................................................................................................... Elwendia bucharica

- Terminal segments of radical leaves more than 3.5 mm long; bracteoles 2–4; petals with solitary secretory ducts; styles slightly spreading or hooked..........................................................................................................................................................................7.

7. Terminal segments of radical leaves linear, 4–6 mm long, 0.7–1 mm wide; terminal umbels pedunculate with 2–7 rays; pedicels up to 7 mm long; stylopods without vallate-thickened margin; styles 1.2–1.3 mm long........................................... Elwendia schistosa

- Terminal segments of radical leaves lanceolate or linear-lanceolate, 3.5–7 mm long, 0.9–2.5 mm wide; terminal umbels sessile with 1–3 rays; pedicels up to 3 mm long; stylopods with vallate-thickened margin; styles 0.7–0.8 mm long................................................................................................................................................................................................................. Elwendia darwasica

8. Stem leaves with extended ovate-lanceolate sheaths........................................................................................... Elwendia varsobica

- Stem leaves with narrowly linear or lanceolate sheaths....................................................................................................................9.

9. Pedicels at fruiting sometimes strongly thickened, divaricate; fruits hardly separating into mericarps.........................................10.

- Pedicels at fruiting thin, not divaricate; fruits easily separating into mericarps.............................................................................12.

10. Terminal segments of radical leaves ovate; terminal segments of uppermost stem leaves lanceolate or linear; pedicels at fruiting distinctly divaricate; fruits with a beak 2.5–3 mm long.......................................................................................... Elwendia latiloba

- Terminal segments of radical leaves linear; terminal segments of uppermost stem leaves filiform; pedicels at fruiting slightly divaricate; fruits without a beak......................................................................................................................................................11.

11. Terminal segments of uppermost stem leaves 3–5 mm long; umbels with 2–3 rays; mericarps narrowly linear, 4.5–5.5 mm long, 0.4–0.7 mm wide.................................................................................................................................................. Elwendia kuhitangi

- Terminal segments of uppermost stem leaves 7–12 mm long; umbels with 5–10 rays; mericarps linear, 4.2–6.5 mm long, 1–1.5 mm wide............................................................................................................................................................................. Elwendia salsa

12. Stems hollow; fruits without a sharp smell........................................................................................................ Elwendia intermedia

- Stems solid; fruits with a sharp, sometimes agreeable, smell... 13.

13. Bracts 3–6; endosperm with a hollow at the commissural side; vallecular vittae 2–3 (1 wide and 1–2 narrow).................................................................................................................................................................................................... Elwendia badachschanica

- Bracts absent or 1–2; endosperm almost flat at the commissural side; vallecular vittae solitary...................................................14.

14. Radical leaves differ sharply from upper stem leaves, their terminal segments incised into small ovoid lobules; umbels at fruiting spherical; pedicels 2–4 times longer than fruits; petals triangular, cuneate at the base........................................... Elwendia persica

- Radical leaves similar to upper stem leaves, their terminal segments incised into lanceolate lobules; umbels at fruiting corymbose; pedicels up to 1.5 times longer than fruits; petals elliptic..................................................................................... Elwendia hissarica