Calea, Linnaeus , 1763

Bueno, Vinicius R., Cassol, A. P. V., Leroy, C. J., Bueno, M. L. & Heiden, Gustavo, 2023, Two noteworthy Calea (Asteraceae: Neurolaeneae) from contact areas of the Atlantic Forest and Cerrado of Brazil, Phytotaxa 579 (3), pp. 143-161 : 155-156

Key to the species of Calea from the states of Paraná and São Paulo, Brazil

1. Discoid capitulum..............................................................................................................................................................................2.

- Radiate capitulum..............................................................................................................................................................................5.

2. Outer phyllaries scarious ...................................................................................................................................................................3.

- Outer phyllaries foliaceous................................................................................................................................................................4.

3. Capitulescences umbelliform; pappus scales 1.8–4.2 mm long................................................................................... C. lantanoides

- Capitulescences cymose; pappus scales 0.2–1.1 mm long.......................................................................................... C. polycephala

4. Venation acrodromous basal; pappus scales 4–5 mm long ......................................................................................... C. gentianoides

- Venation hyphodromous; pappus scales 0.2–0.3 mm long............................................................................................ C. senecioides

5. Leaf margins thickened and white.....................................................................................................................................................6.

- Leaf margins slender and green.........................................................................................................................................................7.

6. Leaves discolorous, abaxial surface glandular-punctate; cypselae 2–2.5 mm ....................................................................... C. ilienii

- Leaves concolorous, abaxial surface eglandular; cypselae 3.2–3.6 mm ................................................................... C. monocephala

7. Capitulescence umbelliform..............................................................................................................................................................8.

- Capitulescence cymose dichasial or capitula solitary .....................................................................................................................10.

8. Leaves whorled..................................................................................................................................................................................9.

- Leaves decussate .............................................................................................................................................................................11.

9. Leaf limb elliptic; receptacle conic ........................................................................................................................... C. mediterranea

- Leaf limb obovate or oblanceolate or rhombic; receptacle convex.................................................................................................10.

10. Leaves crowded in a basal rosette; ray floret corolla 9.8–11 mm long ............................................................................... C. acaulis

- Leaves evenly distributed along the stems; ray floret corolla 11.3–14.7 mm long............................................................. C. cymosa

11. Leaves serrate; capitulescence congest ............................................................................................................................... C. serrata

- Leaves crenate; capitulescence lax................................................................................................................................ C. pinnatifida

12. Habit herbaceous .............................................................................................................................................................................13.

- Habit shrubby ..................................................................................................................................................................................18.

13. Leaves 0.04–0.1 cm wide, linear; involucre 8.4–13.4 mm long, receptacle oligopaleaceous .................................... C. graminifolia

- Leaves 0.6–4.5 cm wide, ovate to lanceolate or elliptic or obovate to orbiculate; involucre 14.1–25 mm long, receptacle holopaleaceous ................................................................................................................................................................................14.

14. Leaf blade ovate; peduncle strigose to scabrous or tomentose........................................................................................................15.

- Leaf blade elliptic or obovate to orbiculate; peduncle velutinous or hirsute ..................................................................................16.

15. Receptacle convex, paleae 9–13 mm long; tube of ray florets 3–5 mm long .................................................................... C. uniflora

- Receptacle conic, paleae 14–20 mm long; tube of ray florets 6–7.5 mm long ............................................................. C. verticillata

16. Leaf limb elliptic, apex acute; peduncle hirsute; receptacle convex .......................................................................... C. clausseniana

- Leaf limb obovate to orbiculate, apex rounded; peduncle velutinous; receptacle conic.................................................................17.

17. Outermost series of phyllaries longer than the second and third series ............................................................................ C. pohliana

- Outermost series of phyllaries shorter than the second and third series.......................................................................... C. cuneifolia

18. Leaves sessile, limb linear, venation hyphodromous; disc florets 5–10; pappus scales 0.2–0.5 mm long ................. C. hymenolepis

- Leaves petiolate, limb ovate or lanceolate or elliptic or deltate, venation acrodromous basal or reticulate or eucamptodromous; disc florets 15–75; pappus scales 0.7–3.0 mm long................................................................................................................................19.

19. Leaf base attenuate; two outermost series of phyllaries 12.2–20 mm long; corolla of ray florets 16.9–31 mm long ......................... ....................................................................................................................................................................................... C. grandiflora

- Leaf base rounded or cordate or truncate; two outermost series of phyllaries 3.3–11.2 mm long; corolla of ray florets 7.4–16.5 mm long................................................................................................................................................................................. C. marginata

20. Stems corrugated, puberulous or puberulent; leaves chartaceous, margins flat.............................................................. C. parvifolia

- Stems striated, hispid to hispidulous, strigose, rarely glabrous; leaves coriaceous, margins revolute............................................21.

21. Second series of phyllaries pubescent to puberulous; ray floret corolla 15.3–17 mm long, limb 12.5–13.5 mm long ....................... ......................................................................................................................................................................................... C. pruskiana

- Second series of phyllaries strigose or glabrous or hispid; ray floret corolla 7.4–14.2 mm long, limb 5.9–10.5 mm long ...........22.

22. Leaf abaxial surface glabrous; cypsela angles hirsute............................................................................................. C. subintegerrima

- Leaf abaxial surface sparsely scabridous or scabridulous; cypsela angles pilose ...........................................................................23.

23. Leaf base cordate; third series of phyllaries eglandular; receptacle paleae conduplicate .................................................. C. triantha

- Leaf base rounded or subcordate; third series of phyllaries glandular-punctate; receptacle paleae concave ............ C. × parviantha