1. Tepals filamentous, subulate or scale-like, free, 2--20, not enclosing young flowers; young flowers totally enclosed in a spathella (a sack-like cover); ovary 2-locular

- Tepals broad and imbricate, oblanceolate to ovate, 3--6, free or united below, enclosing the young flowers; young flowers may be enveloped by a few leaves but never enclosed in a spathella; ovary 2- or 3-locular

3


2

2. Tepals 5 or rarely 4 or 6; stamens 5--25; capsule opening by 2 valves (Northern to central South America)

- Tepals 3; stamens 1, 2 or rarely 3; capsule opening by 3 valves (America, also in Africa, Madagascar, Malaysia, Australia)

1. Weddellina

2. Tristicha

3. Spathellas containing 10--20 flowers (Colombia)

- Spathellas containing a single flower

15. Macarenia

4

4. Flowers not in 2-sided, raceme-like inflorescences; leaves not rough, without wart-like and prickle-like processes on the upper surface

- Flowers in 2-sided, simple or branched, raceme-like inflorescences; leaves with (more rarely without) warts and/or prickles on the upper surface

7


5

5. Stamen filaments united to halfway or slightly less, forming a tube below (Brazil)

- Stamen filaments free or rarely some united at the very base, not forming a tube below, usually persisting in fruit

21. Tulasneantha

6

6. Stamen filaments flat, widened and wing-like, elliptic, membranous,; stigmas flattened, crested (Brazil)

- Stamen filaments linear, terete, not winged; stigmas linear or spatulate, not crested (widespread in South America)

13. Lonchostephus

17. Mourera

7. Capsules strongly asymmetrical when viewed laterally; upper capsule valve smaller and narrower than the lower and almost free from the pedicel, the lower valve saucer-shaped (central Brazil)

- Capsules symmetrical or asymmetrical when viewed laterally; upper and lower capsule valves distinctly attached to the pedicel, boat- or cup-shaped

6. Castelnavia

8

8. Roots thread-like, cylindrical or sometimes somewhat flattened

- Roots usually distinctly flattened, ribbon-like

9

14

9. Shoots solitary, borne at irregular intervals along the root (SE Brazil)

- Shoots in ± opposite pairs, borne at almost regular intervals along the root

10. Devillea

10

10. Leaves bearing 3--8 digitally arranged segments on expanded and sheathing bases (Minas Gerais, Brazil)

- Leaves simple or forked, never digitate

11. Diamantina

11

11. Capsules smooth; stigmas palmately lobed or (in Crenias glazioviana) simple (SE Brazil)

- Capsules ribbed; stigmas simple

9. Crenias

12

12. Capsules with 2 subequal or unequal valves, the suture slightly acentric; stamens 2 or rarely 1 or 3 (C & South America)

- Capsules with 2 equal or subequal valves, the suture centric or nearly so

18. Oserya

13

13. Flowering stems sympodially branched, elongate, each module bearing 2 or rarely 1 leaf (widespread in South America)

- Flowering stems simple and short, each one bearing several leaves (NE South America)

5. Apinagia

12. Jenmaniella

14. Ovary enclosed within the ruptured spathella during anthesis, only stigmas and stamens projecting; stamen 1 (Minas Gerais, Brazil)

- Ovary emerging above the ruptured spathella during anthesis; stamens 2 or more, or rarely 1 in some flowers

8. Cipoia


15

15. Stamens 2 or more, free

- Stamens normally 2, united below or borne on an andropodium, occasional flowers with 1 stamen

19

16

16. Stigmas persisting in fruit, horn-like; midrib of each capsule valve running into the stigma (SE Brazil)

- Stigmas withering after anthesis, simple or palmately branched, never horn-like; midrib of each capsule valve not running into the stigma

7. Ceratolacis

17

17. Capsules smooth, not ribbed, globose; stigmas palmately lobed or (in Crenias glazioviana) simple, with hair-like papillae (SE Brazil)

- Capsule valves with 3 ribs, ovoid to spindle-shaped; stigmas simple, with inconspicuous papillae

9. Crenias


18

18. Capsules ellipsoidal, opening by 2 equal valves; pollen shed in monads (mainly NE South America)

- Capsules ovoid, opening by 2 unequal valves, the larger usually persistent; pollen shed in dyads (tropical to temperate America)

12. Jenmaniella

19. Podostemum

19. Stigmas flattened, lobed or serrated at the apex, somewhat resembling a cock's comb (C Brazil)

- Stigmas terete or flattened, when flattened then entire or toothed but not resembling a cock's comb

14. Lophogyne

20

20. Capsules flattened; midrib of each capsule valve winged, the remaining ribs  unwinged (N South America)

- Capsules terete; midrib of the capsule valves not winged or if winged then other ribs also winged

20. Rhyncholacis

21

21. Pinnae and pinnules of the leaves with scale-like stipels; capsule valves with 5 ribs (S Brazil)

- Pinnae and pinnules naked, without free stipels; capsule valves with 1--7 ribs

23. Wettsteiniola

22

22. Capsule valves with 5 or 7 ribs (C & South America)

- Capsule valves with 3 or less ribs or furrows

5. Apinagia

23

23. Stems elongate, frequently branched (C & South America)

- Stems very short, never branched

5. Apinagia

24

24. Capsule valves without ribs or with 3 grooves or stripes

- Capsule valves with 3 ribs

5. Apinagia

25

25. Capsule ribs winged (West Indies, C & NW South America)

- Capsule ribs not winged

16. Marathrum

26

26. Stigmas linear, not toothed (C & South America)

- Stigmas boat- or spoon-shaped, often toothed

5. Apinagia

27

16. Marathrum


22. Vanroyenella