Acalypha, , Pax & Hoffmann, 1924

Muñoz-Rodríguez, Pablo, Cardiel, José María & Atha, Daniel, 2014, Acalypha subgenus Linostachys (Euphorbiaceae, Acalyphoideae): a global review, Phytotaxa 166 (3), pp. 199-221 : 204-205

Key to the species of Acalypha subgenus Linostachys

1. Inflorescences bisexual, axillary; leaf blades with axils of the secondary nerves barbate [African plants] .......................... 2

- Inflorescences unisexual, terminal or axillary; very rarely bisexual with male flowers distal ( A. flagellata ) or proximal ( A. paniculata ); leaf blades with axils of the secondary nerves not barbate [American plants except A. paniculata of Africa and Asia] ....................................................................................................................................................................................... 7

2. Inflorescences with female flowers proximal and male flowers distal............................................................12. A. gillmanii

- Inflorescences with female flowers distal and male flowers proximal .................................................................................. 3

3. Leafy branches often ending in stiff pungent spines; leaf blades coriaceous, the apex rounded................ 27. A. sonderiana

- Leafy branches usually unarmed (older branch sometimes spinescent in A. acrogyna ); leaf blades membranous to chartaceous, the apex rounded to acuminate.................................................................................................................................... 4

4. Leaf blades narrowly oblong-lanceolate, 1.5– 2 cm broad, the base cuneate; ovary hirsute, not echinate ..... 2. A. boiviniana

- Leaf blades elliptic to ovate-lanceolate, to 2.5–6(– 8) cm broad, the base rounded to subcuneate; ovary echinate, glabrous or pilose .................................................................................................................................................................................. 5

5. Leaf blades chartaceous; ovary glabrous, with sessile glands .............................................................................6. A. echinus

- Leaf blades membranaceous; ovary densely pilose, eglandular ............................................................................................ 6

6. Petioles 0.3– 1 cm long; female flowers 1–3 in each inflorescence .................................................................. 1. A. acrogyna

- Petioles 2.5– 8 cm long; female flowers 10–15 in each inflorescence..................................................................8. A. engleri

7. Female inflorescences usually terminal, rarely also axillary, paniculate ............................................................................... 8

- All female inflorescences axillary, racemose or paniculate ................................................................................................... 9

8. Leaf blades palmately nerved........................................................................................................................21. A. paniculata

- Leaf blades pinnately nerved ...................................................................................................................... 5. A. costaricensis

9. Leaf blade usually pinnately (sometimes pinnipalmately) nerved....................................................................................... 10

- Leaf blade palmately nerved ................................................................................................................................................ 23

10. Female inflorescences racemose; pedicels of the female flowers to (0.5 –) 1–2 mm in anthesis..........................................11

- Female inflorescences paniculate, sometimes racemose when young; pedicels to 5–9 mm long in anthesis ..................... 19

11. Leaf blades subsessile or with petioles to 4 mm long, with or without glandular hairs; lateral veins 10–15(–20) per side 12

- Leaf blades with petioles usually more than 5 mm long, without glandular hairs; lateral veins (4–)6–10(–15) per side ... 13

12. Leaf blades rounded at the base, usually symmetrical, with glandular hairs at margin....................................... 19. A.mutisii

- Leaf blades cordate at the base, strongly asymmetrical, without glandular hairs.................................... 14. A. inaequilatera

13. Leaves deciduous, the blades with (3–)4–5 veins per side; female inflorescences usually to 4 cm long........................... 14

- Leaves evergreen, the blades with (5–)6–15 veins per side; female inflorescences more than 8 cm long.......................... 15

14. Female flowers sessile; petioles 0.2– 1 cm long ..................................................................................................... 9. A. filipes

- Female flowers with pedicels 1–4 mm long; petioles 0.5– 5 cm long............................................................. 26. A. seleriana

15. Petioles 3–8 cm long; leaf blades with 6–8 veins per side.......................................................................17. A. longipetiolata

- Petioles to 2.5 cm long (rarely to 4.5 in A. gentlei ); leaf blades with 7–10(–15) veins per side ......................................... 16

16. Leaf blades linear to narrowly oblong˗lanceolate, slightly falcate ................................................................ 24. A. salicifolia

- Leaf blades ovate, elliptic or obovate˗lanceolate, not falcate .............................................................................................. 17

17. Leaf blades ovate to elliptic˗lanceolate; ovary with glandular hairs............................................................. 3. A. castroviejoi

- Leaf blade obovate-lanceolate; ovary without glandular hairs ............................................................................................ 18

18. Leaf blades glabrous or subglabrous (a few appresed hairs on veins in young leaf), the apex caudate˗acuminate, the acumen to 2.5 cm long......................................................................................................................................20. A. oblancifolia

- Leaf blades densely pubescent, the apex slightly acuminate .............................................................................. 11. A. gentlei

19. Petioles to 6(–8.5) cm long; leaf blades to 17(–30) cm long ............................................................................................... 20

- Petioles to 2.5(–4) cm long; leaf blades to 13 cm long (to 18 cm in A. schlechtendaliana )................................................ 21

20. Leaf blades with 10–17 veins per side; female inflorescences as long as the leaves................................... 23. A. platyphylla

- Leaf blades with 6–7 veins per side; female inflorescences much shorter than the leaves ...................... 15. A. leptorhachys

21. Young branches and inflorescences with glandular hairs ................................................................................ 16. A. longipes

- Young branches and inflorescences without glandular hairs ............................................................................................... 22

22. Leaf blades lustrous and glutinous to the touch even in dried specimens ....................................................13. A. gummifera

- Leaf blades neither lustrous nor glutinous ........................................................................................ 25. A. schlechtendaliana

23. Leaf blades with minute, lustrous resinaceous droplets, mainly on the abaxial surface; female inflorescences racemose or paniculate; ovary glabrous................................................................................................................................... 28. A. villosa

- Leaf blades without resinaceous droplets; female inflorescences racemose; ovary glabrous or pilose............................... 24

24. Leaf blades to 4–6(–12) cm long; petioles 4–6(–7) cm long..........................................................................10. A. flagellata

- Leaf blades to 15(–20) cm long; petioles (4–)8–17(–23) cm long....................................................................................... 25

25. Leaf blades deeply cordate at the base ................................................................................................................................. 26

- Leaf blades obtuse, rounded or slightly cordate at the base................................................................................................. 27

26. Young branches tomentose to velutinous; female flowers sessile.................................................................7. A. elizabethae

- Young branches hirsute with long stiff hairs; female flowers with pedicels to 1 mm long........................18. A. muelleriana

27. Leaf blades elliptic to ovate; female flowers sessile; ovary with long hairs to 1 mm long ................................ 22. A. pittieri

- Leaf blades broadly ovate lanceolate; female flowers with pedicels to 1 mm long; ovary usually glabrous, rarely hispidulous with minute hairs ...................................................................................................................................... 4. A. chocoana