Navia Martius ex Schultes filius in Roemer & Schultes, Syst. 7(2): lxv, 1195, 1830.
Desc from S&D
Tall amply particulate herbs to small scapeless cushion-forming types, stemless or caulescent. Leaves numerous, rosulate or in a dense spiral along the stem;
sheaths usually ample;
blades narrow, sometimes somewhat narrowed toward base, entire or more or less serrulate. Scape usually lacking, rarely well developed.
Inflorescence terminal, usually capitate but sometimes paniculate.
Floral bracts conspicuous;
flowers sessile or subsessile, perfect.
Sepals imbricate, the two posterior covering the anterior or rarely the anterior completely lacking, free to high-connate;
petals high-connate in a slender tube, naked; blades spreading at anthesis, usually lanceolate and acute;
stamens of the second series highly adnate to the petals; anthers linear;
ovary usually superior but rarely to wholly inferior, glabrous; style slender; placentae linear; ovules naked or nearly so.
Capsule usually dehiscent;
seeds reticulate, naked or soon losing the vestigial wing.
TYPE. Navia caulescens Martius ex Schultes filius in Roemer & Schultes, Syst. 7(2): 1195, 1830.

1. Inflorescence evidently scapose, the scape > 5 cm long => 2
l. Inflorescence sessile, or short-pedunculate with scape < 4 cm long and usually hidden among the leaves => 4

2(1). Inflorescence a loose panicle, the flowers borne singly along the branches => N. lindmanioides
2. Inflorescence a dense spike, the spike heads either clustered at the scape apex or => 3

3(2). Heads borne in a cluster at apex of scape; leaves glabrescent, 9-20 cm long => N. luzuloides
3. Heads borne along the scape as well as at apex; leaves densely appressed lepidote on lower surface, 30-90 cm long => N. scirpiflora

4(1). Indument (excluding spine or tooth axils) of simple, linear trichomes (use 10x magnification and hold against light) => 5
4. Leaf indument of branched, squamiform, or radiate trichomes, or leaves glabrous => 31

5(4). Larger leaves > 2 cm wide => 6
5. Larger leaves < 2 cm wide => 12

6(5). Floral bracts > 2 cm long => 7
6. Floral bracts < 2 cm long => 9

7(6). Floral bracts > 4 cm long, ovate with a long, recurved, acuminate-caudate apex => N. tentaculata
7. Floral bracts 2-3 cm long, apex lanceolate to narrowly lanceolate, recurved to straight => 8

8(7). Corolla white; anthers included => N. sp. A
8. Corolla yellow or yellow-orange; anthers long-exserted => N. wurdackii

9(6). Spines near base of leaf blade 2-4 mm long => N. stenodonta
9. Spines near base of leaf blade < 1 mm long => 10

10(9). Primary bracts within the inflorescence > 2 times exceeding the flowers => N. paruana
10. Primary bracts within the inflorescence shorter than, to just surpassing the flowers => 11

11(10). Floral bracts recurved apically; inflorescence branches distinguishable, conical or ovoid and the inflorescence appearing lobed => N. sp. B
11. Floral bracts incurved or straight; inflorescence branches not distinguishable, entire inflorescence appearing convex (to globose in fruit) => N. aliciae

12(5). Inflorescence simple => 13
12. Inflorescence densely bipinnate or digitately compound with several to many sessile heads (in species with tightly grouped heads, this is best seen in longitudinal section of the inflorescence or in infructescences) => 18

13(12). Leaf blades entire above middle; inflorescence longer than broad, 2-3 cm long => N. polyglomerata
13. Leaf blades spinulose the entire length; inflorescence as long as broad or broader than long => 14

14(13). Sepals 3-8 mm long; floral bracts < 10 mm long. => 15
14. Sepals 10-15 mm long; floral bracts > 10 mm long => 16

15(14). Leaves 4-8 cm long, margins undulate; inflorescence few-flowered, 4-6 mm wide; floral bracts bearing gland-tipped trichomes, broadly ovate, not contracted; plants stoloniferous => N. glandulifera
15. Leaves 10-20 cm long, margins plane; inflorescence many-flowered, 15-25 mm wide; floral bracts with nongland-tipped trichomes, lanceolate, slightly contracted just above middle; plants not stoloniferous. => N. huberiana

16(14). Leaf blades ca. 6 mm wide; ovary 1/2 inferior => N. scopulorum
16. Leaf blades 8-18 mm wide; ovary superior => 17

17(16). Leaf blades coriaceous, stiff, marginal spines black; corolla yellow-green => N. crassicaulis
17. Leaf blades membranous, linear, marginal spines green or light brown; corolla white => N. steyermarkii

18(12). Leaf margins entire, densely lanose. => N. lanigera
18. Leaf margins serrulate or spinulose, glabrous or lepidote, if entire, never lanose => 19

19(18). Sepals obtuse to subacute, often cucullate. => 20
19. Sepals acute or acuminate to attenuate, sometimes incurved, but never cucullate => 21

20(19) Leaf blades ca. 20 mm wide; floral bracts suborbicular, distinctly shorter than the sepals => N. breweri

20. Leaf blades ca. 9 mm wide; floral bracts broadly ovate, about equaling the sepals => N. navicularis
21(19). Floral bracts distinctly spinulose or serrulate => 22

21. Floral bracts entire or nearly so => 24
22(21). Primary and floral bracts green => N. viridis

22. Primary and floral bracts bright red or pink => 23
23(22). Leaf blades > 18 cm long; spinule axils glabrous or sparsely barbellate => N. phelpsiae

23. Leaf blades < 14 cm long; spinule axils densely barbellate => N. trichodonta
24(21). Inner leaves and/or inflorescence bracts colored, red, pink, rose, white, or greenish white => 25
24. Inner leaves and inflorescence bracts green => 28

25(24). Leaves green; inflorescence bracts bright red or pink => N. phelpsiae
25. Inner leaves and inflorescence bracts rose, white, or greenish white. => 26

26(25). Corolla yellow; floral bracts smooth, lustrous => N. colorata
26. Corolla white; floral bracts striate, dull => 27

27(26). Individual flower heads 5-7 mm in diameter; inflorescence flat-topped or shallowly lobed at anthesis => N. sp. C
27. Individual flower heads 10-15 mm in diameter; inflorescence deeply lobed => N. polyglomerata

28(24). Spines on basal portion of leaf blade >_ 1 mm long => N. crispa
28. Spines on basal portion of leaf blade < 0.5 mm long, or basal portion of blade entire => 29

29(28). Leaf blades serrulate only in distal 1/4. => N. filifera
29. Leaf blades spinulose or serrulate their entire length, or serrulate only basally => 30

30(29). Sepals 13 mm long; inflorescence sessile or peduncle < 1 cm long => N. patria
30. Sepals 8 mm long; inflorescence pedunculate, the peduncle 1-3.5 cm long, often hidden among the leaf bases => N. polyglomerata

31(4). Ovary about ½ inferior (the inferior portion sometimes appearing as a broad pedicel); corolla yellow, orange, or cream (not known in N. immersa); inflorescence simple => 32

31. Ovary wholly superior; corolla color various => 40
32(31). Leaves > 15 mm wide => 33

32. Leaves < 10 mm wide => 34
33(32). Inner leaves and bracts at anthesis reddish or tinged maroon; stem poorly developed or lacking. => N. arida
33. Inner leaves and bracts at anthesis basally yellow, often grading into orange, red, and green apically; stem well developed => N. igneosicola

34(32). Sepals 28-30 mm long. => N. immersa
34. Sepals 7-15 mm long. => 35

35(34). Leaf blades 9 mm wide, sparsely arachnoid-lepidote; stems usually > 30 cm long => N. aloifolia
35. Leaf blades 3-6 mm wide, sparsely to densely lepidote; stems usually < 20 cm long => 36

36(35). Anthers included => N. pulvinata
36. Anthers exserted => 37

37(36). Calyx irregular, the anterior sepal (opposite the floral bract) greatly reduced or lacking; basal spinule axils glabrous or squamose-barbellate => 38
37. Calyx regular, the sepals equal in length or nearly so; basal spinule axils long-arachnose-barbellate => 39

38(37). Lower surface of leaf blades densely covered with appressed, lepidote scales; anterior much reduced => N. lepidota
38. Lower surface of leaf blades glabrous or only sparsely lepidote; anterior sepal lacking => N. parvula

39(37). Lower surface of leaf blades glabrous => N. aurea
39. Lower surface of leaf blades densely covered with appressed, lepidote scales => N. liesneri

40(31). Lower surface of leaf blades, at least when young, completely covered with appressed, peltate-scales (not to be confused with a glaucous covering, use 10x magnification) => 41
40. Lower surface of leaf blades glabrous to peltate- or stellate-lepidote, but the scales never completely covering the surface => 49

41(40). Inflorescence bracts and basal part of inner leaves green, or at least not conspicuously colored => 42
41. Inflorescence bracts and basal part of inner leaves white, creamy, or red => 45

42(41). Leaves 11-19 mm wide => N. nubicola
42. Leaves 3-5 mm wide => 43

43(42). Sepals acute => N. duidae
43. Sepals obtuse => 44

44(43). Floral bracts acute => N. semiserrata
44. Floral bracts obtuse => N umbratilis

45(41). Leaves > 20 cm long; inflorescence bracts and basal part of inner leaves red; inflorescence compound => N. mosaica
45. Leaves < 15 cm long; inflorescence bracts and basal part of inner leaves white or cream; inflorescence simple => 46

46(45). Sepals connate => 47
46. Sepals free => 48

47(46). Leaf blades slightly contracted at base, the lower surface soon glabrous => N. pungens
47. Leaf blades not contracted at base, the lower surface persistently lepidote => N. mima

48(46). Leaf blades 12 mm wide; sepals 7 mm long => N. incrassata
48. Leaf blades 3-4 mm wide; sepals 14 mm long => N. lasiantha

49(40). Inflorescence compound => 50
49. Inflorescence simple => 56

50(49). Inflorescence bracts and basal part of inner leaves white at anthesis => N. jauana
50. Inflorescence bracts and inner leaves green, red, pink, or yellow at anthesis => 51

51(50). Sepals > 3 cm long => N. splendens
51. Sepals < 2 cm long => 52

52(51). Sepals 6-8 mm long => 53
52. Sepals 13-15 mm long => 54

53(52). Floral bracts suborbicular, distinctly shorter than the sepals; leaf blades ca. 20 mm wide => N. breweri
53. Floral bracts broadly ovate, about equaling the sepals; leaf blades ca. 9 mm wide => N. navicularis

54(52). Upper surface of leaf blades densely stellate-lepidote; corolla yellow; primary and floral bracts drying pale brown, thick, stiff, smooth, and lustrous => N. involucrata
54. Upper surface of leaf blades glabrous; corolla white (not known in N. robinsonii); primary and floral bracts drying whitish, tan, or dark brown, thin => 55

55(54). Foliar scales peltate, their edges touching; floral bracts and calyx drying tan to dark brown, reddish brown peltate-lepidote apically => N. nubicola
55. Foliar scales stellate, sparse to dense; floral bracts and calyx drying whitish, glabrous => N. robinsonii

56(49). Larger leaf blades > 7 mm wide => 57
56. Larger leaf blades ≤ 7 mm wide => 70

57(56). Floral bracts serrate => 58
57. Floral bracts entire => 61

58(57). Lower surface of leaves cretaceous or farinose => 59
58. Lower surface of leaves glabrous => 60

59(58). Sepals smooth; leaf blades 8-13 mm wide => N cretacea
59. Sepals strongly nerved; leaf blades ca. 20 mm wide => N. latifolia

60(58). Leaf blades with a distinct, broad, central longitudinal band; leaves membranous when dry, blade margins undulate, teeth the same color as the blade => N. octopoides
60. Leaf blades lacking a central longitudinal band; leaves thick, stiff, blade margins plane (or revolute?), spines black when dry, contrasting with the green or brown blades => N. crassicaulis

61(57). Leaf blades entire or serrulate only at base or apex => 62
61. Leaf blades serrate or spinulose for at least 3/4 their length => 64

62(61). Sepals acute, 10-13 mm long => N connata
62. Sepals obtuse, 12-16 mm long => 63

63(62). Sepals 12 mm long, connate for at least 0.5 their length; leaves green => N. affinis
63. Sepals 16 mm long, connate for < 0.3 their length; inner leaves basally white => N. subpetiolata

64(61). Sepals connate => N. pungens
64. Sepals free to the base => 65

65(64). Posterior sepals acute to acuminate => N. glauca
65. Posterior sepals obtuse to rounded => 66

66(65). Keel of the posterior sepals dilated below the apex => N. xyridiflora
66. Keel of the posterior sepals linear or broader at base or middle => 67

67(66). Sides of the posterior sepals 2 mm wide, their keels narrow or broad => N. linearis
67. Sides of the posterior sepals 1 mm wide, their keels very narrow => 68

68(67). Lower surface of leaf blades squamose, glaucous => N. pauciflora
68. Lower surface of leaf blades glabrous => 69

69(68). Floral bracts oblong, broadly acute => N. caurensis
69. Floral bracts suborbicular, broadly rounded => N. ovoidea

70(56). Sepals connate, either all together equally, or only the two posterior ones connate => 71
70. Sepals free => 78

71(70). Leaf blades entire or with a few obscure teeth at apex or base => 72
71. Leaf blades serrulate or spinulose throughout => 75

72(71). Leaf blades strict, involute, 3 mm wide => N. caricifolia
72. Leaf blades spreading, flat, (3-)5-10 mm wide => 73

73(72). Corolla yellow => N. connata
73. Corolla white => 74

74(73). Sepals 10 mm long => N. gleasonii
74. Sepals 13-14 mm long => N. carnevalii

75(71). Inner leaf blades same color as outer ones => N. terramarae
75. Inner leaf blades white at base => 76

76(75). Leaf blades 8-13 mm wide; narrowed basally => N. pungens
76. Leaf blades 1-4 mm wide => 77

77(76). Posterior sepals 15 mm long, over 3/4 connate; leaf blades 4 mm wide => N. lactea
77. Posterior sepals 10 mm long, 1/4 connate; leaf blades 1-2 mm wide => N. ocellata

78(70). Sepals acute to acuminate or attenuate, sometimes incurved but never cucullate => 79
78. Sepals obtuse to rounded, often cucullate => 82

79(78). Floral bracts serrulate => N. serrulata
79. Floral bracts entire => 80

80(79). Blades abruptly acute or obtuse; corolla yellow => N. brachyphylla
80. Blades evenly long-attenuate; corolla white => 81

81(80). Sepals 12-14 mm long, entire => N. duidae
81. Sepals 6 mm long, denticulate on the keel => N. saxicola

82(78). Leaf blades entire or serrulate only near base, 6-20 cm long => 83
82. Leaf blades serrulate throughout => 85

83(82). Floral bracts obtuse => N. culcitaria
83. Floral bracts acute => 84

84(83). Inner leaf blades white at base => N. berryana
84. Inner leaf blades same color as outer ones => N. semiserrata

85(82). Floral bracts obtuse => N. cucullata
85. Floral bracts acute => 86

86(85). Floral bracts thickened at apex => 87
86. Floral bracts uniformly thin => 88

87(86). Leaf blades evenly filiform-attenuate => N. geaster
87. Leaf blades abruptly acute => N. intermedia

88(86). Lowest floral bracts serrulate near apex, red-brown; inner leaves not pale at base => N. cardonae
88. Lowest floral bract and all others entire, green; inner leaves pale at base => 89

89(88). Floral bracts broadly elliptic, acute, and mucronulate, about equaling the sepals; leaf blades 3-5 mm wide => N. abysmophila
89. Floral bracts ovate, acuminate, shorter than the sepals; leaf blades 2.5 mm wide => N. emergens

The genus Navia is one of the most beautiful and ornamentally attractive genera of the Bromeliaceae. The genus was established in 1830 by Martius ex Schultes filius, based on a Martius collection from Cupati, Rio Japura (Caqueta) in Amazonas, Colombia, and described as N. caulescens. An additional species, N. acaulis was described at the same time from another Martius collection taken from a different locality in Colombia (Araracuara, in Vaupes-Amazonas). Following the description of these two Colombian species, two more were found in Guyana, N. angustifolia (Baker) Mez, in 1896, based in Cryptanthus angustifolius Baker, and N. gleasonii L.B. Smith in 1930.

With the exploration of Mount Duida, famous sandstone table mountain of the "Lost World" of the Venezuelan Guayana, in 1929-1930 by G.H.H. Tate of the American Museum of Natural History, two more species, Navia brachyphylla and N. duidae, the first ones known from Venezuela, were described by Lyman B. Smith.

Continued exploration of these sandstone mountains, as well as the surrounding lowlands of igneous outcrops and white sand savannas, has increased tremendously the number of species. By the year 1974 when Dr. Smith's treatment of the genus appeared in Flora Neotropica, 74 species were already known, principally from the Venezuelan Guayana from expeditions made by Maguire, Cowan, Wurdack, Cardona, and Steyermark. Since 1974 to the present, the number of species has increased to well over 100 through the expeditions principally made by Huber, Liesner, Steyermark, Davidse, Plowman, Thomas, and others. The majority of these novelties have come from the summits or escarpments of the sandstone mountains, but no end is in sight for the number of future species to be discovered and added, since it appears that each new expedition to previously unexplored sectors of the Roraima Formation in Venezuela, Guyana, Colombia, and northern Brazil yields additional taxa of the genus.

After these many years during which the genus has been known and available for study, one would assume that the basic floral structure of Navia would be sufficiently documented. In Dr. Smith's monumental publication of the Bromeliaceae for the Flora Neotropica, the corolla of Navia is described as having the "petals high-connate in a slender tube." During many years of collecting in the Venezuelan Guayana, I had never taken the opportunity of actually examining in detail the corollas of Navia, and apparently others had likewise failed to do so. The reasons for this neglect are several: Navias often are found in sites difficult of access or remotely distant from base camp, and with limited time at one's disposal, after a large collection has been accumulated during a day's trip, the major effort is made to enter the numerous collections and their data into the field notebook. In the case of Navia, attention was given principally to the color of corollas, bracts, and leaves, as well as habit and habitat. This limitation of time for the preparation of specimens diverted attention from detailed examination of the corolla under living conditions. Added further to the problem has been the lack of success in growing Navia. This has hampered close observation of living material. I well remember how the famous horticulturist and explorer of Bromeliaceae, the late Mulford B. Foster, expressed keen disappointment at not being able to grow Navia from seed I had sent him from my collections. Now, Dr. Bogner at the Munich Botanic Garden and Henrique Graf, a grower in Caracas, have been able to cultivate this genus successfully.

During April, 1986, a surprising observation on Navia flowers was made by the author and his assistant, Bruce Holst, while on an expedition to the Rio Coro Coro at the base of Cerro Vutaje in Territorio Federal Amazonas, Venezuela. A beautiful Navia with white corollas and rose-colored bracts was collected and a careful examination made of the living corolla. To our amazement, the petals were found to be completely free from one another and separate from the base, not coalesced as the extant literature had indicated. This Navia was then described as a new species, N. grafii Steyerm. & Holst, named in honor of the bromeliad grower of Caracas, Henrique Graf, who had accompanied us that day together with Parker Redmond, another plant enthusiast from Caracas. In the publication of this new species (Steyermark & Holst 1986) we called attention to our observation that the petals were free or nearly so and that this was at variance with the generic description of the corolla. I thought at the time that this might be an anomalous situation to which I directed Dr. Smith's attention.

However, after later dissections made on several additional species, previously described as well as new ones in the process of being described, showed a similar condition of free or nearly free petals, I began to change my concept of the Navia corolla. Furthermore, Dr. Smith had examined topotypic material of the type species, N. caulescens, and found, after dissection, that the petals of that species were indeed separate. Although this condition of free petals does exist in apparently a number of species of the genus, it is not universal, since an examination of other taxa of the genus reveals a definite corolla tube with the stamens in-serted at various levels. The condition of free petals, on the other hand, was to be expected, since they also occur in such genera of the Pitcairnioideae as Brocchinia, Lindmania, Pitcairnia, Puya, and others.

In the future, collectors should be aware of the variation from free to connate petals, and examine living material carefully to record each species examined. The generic description of Navia must be emended, therefore, as follows: Petala libera vel in tubum varie conjuncta.