1a. Seeds numerous, discoid to flattish D-shaped:

(At flowering time seeds are not at hand for identification purposes. The reader should therefore in each case refer at once to species nos. 45 and 46 as indicated under 1b to see if either description fits his unknown plant. If not, he should proceed with 2a.)

2a. Tepaltube very long, 7.6-13 cm. long (subg. type: A. elegans Spreng.):


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Subgenus 1. MACROPODASTRUM Baker. (THE ELEGANS GROUP)
3a. Stigma trifid; perigone white, greenish-white or green:
4a. Perigone white or greenish-white:
1. immaculata5a. Umbel 6-flowered; flowers sweet-scented, white, suffused greenish at base of tepalsegs, tepaltube greenish (Argentina):

2. tucumana5b. Umbel many-flowered, perigone white (Argentina):

3. viridiflora4b. Perigone green (Bolivia):

4. elegans3b. Stigma triangularly 3-lobed (capitate), or trifid, perigone greenish-white, perigone sulfur-colored with faint crimson stain, or white faintly striped with red (N. Brazil, Guiana, Venezuela, Colombia, Peru and Ecuador?):
4a. elegans var. elegans1a. Perigone entirely greenish-white (N. Brazil, Guiana, Venezuela and Colombia):

1b. Perigone not entirely greenish-white:

4b. elegans var. vittata11a. Perigone sulfur-colored with faint crimson stain along outer keel of tepalsegs, tepaltube purplish-red (Guiana):

IIb. Perigone white or greenish-white striped red, or tepaltube purplish-red:

4c. elegans var. rubritubaIIIa. Perigone greenish-white tepaltube purplish-red (Guiana?):

IIIb. Perigone white, striped with red:

4d. elegans var. striataIVa. Flowers faintly striped with red on outside (Guiana?):

4e. elegans var. ambiguaIVb. Flowers striped with red within (Peru, and Ecuador?):

6a. Paraperigone absent or present; if present, then not incurved, but consisting of bristles, scales or a membranous rim:
7a. Stigma distinctly trifid (see also 24b, below, A. evansiae, sometimes shortly trifid, with thick forks). (subg. type: A. striata Lam.):

8a. Leaves sessile (not petiolate):
9a. Leaves 2-3.9 cm. broad:
l0a. Tepalsegs not extremely irregular:
11a. Spathe not blood-red or red:
12a. Spathe lanceolate, lanceolate-obtuse, or oblong-lanceolate:
13a. Perigone white, or sulfur-colored, sometimes striped, streaked or keeled red:
14a. Pedicels 5-7.5 cm. long:
5. vittata15a. Perigone 10-15 cm. long (Peru and Brazil):
5a. vittata var. vittata Ia. Tepaltube 2.5 cm. long (Peru and Brazil):

5b. vittata var. tweedianaIb. Tepaltube 4.1 or 4.2 cm. long (Central Brazil and Bolivia):

6. breviflora15b. Perigone 6.4 cm. Long (S. Brazil):

7. harrisonii 14b. Pedicels 2.5-3.8 cm. long; perigone white, streaked (Uruguay):

13b. Perigone red-carmine, bright red, nasturtium-red, pale pastel pink, or light yellow and greenish:

8. canterai16a. Scape 80-100 cm. tall (Uruguay):

16b. Scape 16-52 cm. tall:

17a. Tepaltube 0.5-0.9 cm. long:
9. damaziana18a. Perigone bright red (Brazil):

10. aglaiae18b. Perigone light yellow and greenish (Argentina):

11. striata17b. Tepaltube 2-2.5 cm. long (Brazil):

Ia. Tepaltube 2 cm. long:
11a. striata var. striata IIa. Flowers nasturtium-red (Brazil):

IIb. Flowers not nasturtium-red:

11b. striata var. crocataIIIa. Flowers pastel pink (Brazil):

11c. striata var. acuminataIIIb. Flowers pale pink; tepalsegs very acute (Brazil):

11d. striata var. fulgidaIb. Tepaltube 2.5 cm. long; flowers nasturtium-red (Brazil):

12. Crociflora 12b. Spathe oblanceolate-obtuse; flowers rose-purple (Bolivia):

13. flammigera 11b. Spathe blood-red to red (Argentina):

14. maracasa 10b. Tepalsegs quite irregular; perigone bright red, green star in throat (Brazil):

15. angustifo1ia 9b. Leaves 1-1.5 cm. broad (Argentina):

16. petiolata8b. Leaves petiolate (Argentina):

19a. Umbel 2- to 8-flowered:

17. leopoldii20a. Tepalsegs the most regular of all species in the genus (Peru):

20b. Tepalsegs less regular; definitely of 4 different sizes:

21a. Spathe valves of emerging scape closed; valves withering soon after anthesis:
22a. Stamens distinctly fasciculate; leaves 2-4.5 cm. broad:
23a. Tepaltube 2 cm. long, or shorter:
24a. Style longer than one-half of the tepalsegs:
18. stylosa25a. Stamens a little exserted; style much exserted (Guiana and N. Brazil):

25b. Stamens as long as or shorter than the perigone:

26a. Stamens as long as the perigone:
19. scopulorum27a. Style a little exserted (Bolivia):

20. reginae27b. Style as long as the perigone (Mexico and West Indies to Brazil, Peru and West Central Africa):

26b. Stamens shorter than the perigone:
21. andreana28a. Paraperigone absent; flowers rose-red (Columbia): .

22. miniata28b. Obscure paraperigone present; flowers bright red (Peru):

23: evansiae 24b. Style about half the length of the tepalsegs; stamens shorter than style; flowers greenish, or pale yellow (Bolivia):

23b. Tepaltube 2.2-3.1 cm: long:
29a. Plants spring flowering:
30a. Leaves 15-22 cm. long:
24. espiritensis31a. Tepaltube 3 cm. long (Brazil):

25. vanleestenii31b. Tepaltube 2.2 cm. long (Suriname):

30b. Leaves 30-55 cm. long or longer:
26. ferreyrae32a. Pedicels 8-9.5 cm. long; paraperigone absent; flowers red (Peru):

27. belladonna32b. Pedicels 5-7.6 cm. long; paraperigone present; flowers scariet, red, pink or salmon (Mexico and West Indies to Chile, Bolivia and Brazil):

Ia. Perigone scarlet; red or salmon:
IIa. Flowers not double:
27a. belladonna
 var. belladonnaIIIa. Perigone 10-13 cm. long; flowers scarlet, red or salmon (Mexico and West Indies to Chile and Brazil):

27b. belladonna
 var. major IIIb. Perigone longer than 13 cm.; flowers scarlet (British Guiana, West Indies, Brazil, Colombia and Costa Rica):

27c. belladonna
 var. plenaIIb. Flowers semidouble or fully double; scarlet (Cuba):

27d. belladonna
 var. haywardiiIb. Perigone carmine (Bolivia):

29b. Plants summer flowering:
28. barbata33a. Flowers creamy-white (Suriname):

29. barreirasa33b. Flowers rose-red (Brazil):

30. traubii22b. Stamens somewhat spreading; leaves 1.5-1.7 cm. broad (Peru):

31. apertispatha21b. Spathe valves of emerging scape open, and remaining green after anthesis (Brazil):

32. mandonii19b. Umbel l-flowered (Bolivia):

6b. Paraperigone incurved (subg. type: A. aulica Ker-GawI.):

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Subgenus IV. OMPHALISSA (Salisb.) Baker (THE AULICA GROUP)
34a. Perigone not extremely irregular:
33. fosteri35a. Umbel 5- to 13-flowered; tepalsegs extremely reflexed (Brazil):

35b. Umbel 2- to 4-flowered; tepalsegs not extremely reflexed:

36a. Flowers opening fully:
37a. Stigma deeply trifid:
34. calyptrata38a. Flowers green in general aspect, or pale yellow, reticulated green (Brazil):

38b. Flowers crimson, rose, red, scarlet, or veined purplish:

35. kromeri39a. Flowers copiously spotted externally toward the base with red (Brazil):

39b. Flowers not spotted externally with red:

40a. Pedicels shorter than the spathe:
36. psittacina 41a. Perigone crimson with green stripes, or pale yellow veined purplish-scarlet (S. Brazil):
36a. psittacina var. psittacinaIa. Perigone 10-12 cm. long (S. Brazil):

36b. psittacina var. decorataIb. Perigone longer than 12 cm. (S. Brazil):

41b. Perigone crimson without stripes:
37. correiensis42a. Stamens nearly as long as the tepalsegs (Brazil):
37a. correiensis
 var. correiensisIa. Perigone not laterally compressed (S. Brazil):

37b. correiensis
 var. compressaIb. Perigone laterally compressed (S. Brazil):

38. aulica42b. Stamens shorter than the tepalsegs (Brazil and Paraguay):

39. forgetii40b. Pedicels equaling the spathe (Peru):

37b. Stigma subtrifld, lobes globular to faintly trilobed:
40. oconequensis43a. Umbel 4-flowered (Peru):

43b. Umbel 2-flowered:

41. moreliana44a. Flowers bright ochre-red (Brazil):

42. pardina44b. Flowers greenish or yellowish, minutely dotted red (Peru):

43. fusca36b. Flowers never opening more than half (Peru):

44. cybister34b. Perigone extremely irregular, resembling the flower of Sprekelia formosissima (Brazil and Bolivia):

45. reticulata45a. Plants autumn-flowering, leaves sessile, obovate or petiolate (S. Brazi1):
45a. reticulata
 var. reticulataIa. Leaves bright green (S. Brazil):

45b. reticulata
 var. striatifotiaIb. Leaves with a distinct white or pinkish keel (S. Brazil):

46. blumenavia45b. Plants summer-flowering; leaves elliptic to petiolate (S. Brazil):