1.

+

Pappus uniseriate.

2

–

Pappus biseriate, outer setae small, forming a corona.                                                 

12

2.

+

Cypselas 1-ribbed on each side.

3

–

Cypselas more than 1-ribbed on each side.    

4

3.

+

Leaves apically obtuse and  beset with flexuous crisped hairs beneath or at the margins. Cypselas 3–4 mm long  excl. 8–9 mm long beak, beak without  appendages at the base.

6. L. glaucifolia

–

Leaves apically  acute and  without  flexuous crisped  hairs  beneath or at the margins. Cypselas 3–3.5 mm long excl. 1–1.2 cm long  beak, beak with 2, transparent appendages at the base.               

1. L. undulata

4.

+

Middle and upper leaves decurrent. Synflorescence spicate to subracemose. Florets less than 5 in each capitulum.

5

–

Middle and upper leaves not decurrent. Synflorescence not as above. Florets (5-) many in each capitulum.              

7

5.

+

Cypselas not beaked. Pappus not fragile.   

2. L. erostrata    

–

Cypselas beaked. Pappus fragile.

6

6.

+

Plant dichotomously or intricately branched. Cypselas brown, beak slender, 2–3   mm long.   

3. L. orientalis

–

Plant virgately branched. Cypselas black, beak filiform, 3.5 - 8  mm long.      

4. L. viminea

7.

+

Phyllaries pale green. Cypselas brown to dark brown or blackish, beak filiform-capillary, either equalling or 1 ½- 2 times longer than the body, almost discolorous and different in texture. Pappus 3-6 mm long, lemon yellow-white  and persistent.

8

–

Phyllaries pale brown to pink. Cypselas sandy brown to olive or black, beak stout, smaller than the body, usually concolorous   and same in texture. Pappus 10 – 12  mm long, off white-lustrous and   fragile.

9

8.

+

Stem up to 60 cm long, dichotomously branched above. Cypselas 3-ribbed, bidentate or cleft at the tip, muricate, beak 2 times longer than the body. Pappus 3 mm long.

 5. L. dissecta

–

Stem up to 200 cm long, paniculate to corymbosely branched above. Cypselas more than -3 ribbed, pilose, beak equalling or 1 ½ times longer than the  body. Pappus 4–6  mm long.  

11

9.

+

Cauline leaves linear-lanceolate, lower leaves sparingly ½ pinnatifidly lobed, entire. Florets blue or lavender. 

7. L. dolichophylla

–

Leaves not as above. Florets yellow.

10

10.

+

Lower leaves succulent, undivided, minutely and softly spinulose to quite smooth. Cypselas blackish. (Cultivated   plants).          

9. L. sativa

–

Lower leaves non-succulent, variously divided usually runcinate pinnatifid, prickly or spinulose along the  margin and midrib beneath. Cypselas brown. (Wild plants) .

8. L. serriola

11.  

+

Annual  herbs .Stem 15–30  cm tall. Leaves not polymorphous, 5 – 9  x 0.3 – 1  cm, denticulate to entire. Cypselas blackish.

10. L. clarkei

–

Perennial herb. Stem 30 – 80(-100) cm tall. Leaves polymorphous, 10–20  (-25) x 2–4 cm, sinuate to sharply toothed or cartilaginous. Cypselas sandy brown–dark olive or almost black .         

11. L. tatarica

12. 

+

Florets Pink to lavender,  less than 25 in each capitulum.Phyllaries 3-4-seriate. Cypselas with 2–3  mm long beak. Pappus 3 – 4 mm long.

13

–

Florets yellow, more than 25 in each capitulum. Phyllaries 5-6-seriate. Cypselas with 3 – 4  mm or 10 – 12 mm long beak. Pappus 8 – 10 mm long.       

14

13.

+

Phyllaries 20-25, 6 – 10 mm long. Cypselas 5.5 – 7 mm long, red when young, afterwards blackened, cuneate-linear, beak white, up to 3 mm long. Pappus 3 – 4 mm long.

14. L. picridiformis

.

–

Phyllaries 9-15, 11 – 14 mm long. Cypselas 4.5 – 5 mm long, black, fusiform, beak pale or concolorous, up to 2 mm long. Pappus 5 – 6 mm long.

15.L. chitralensis

14.

+

Florets 25-30 per capitulum. Cypselas up to 3 mm  broad. Beak 3 – 4  mm long, smaller than the cypsela.

12. L. crambifolia

–

Florets more than 30 per capitulum. Cypselas up to  4 mm broad. Beak 10 – 12 mm long,   longer than the cypsela.

13. L. persica