Alcantarea Key.
by D Butcher 04/2008.

A. alta and A. regina excluded, A. patriae, A. distractila, A. lurida added.


Key
Identity
Go To
1.
_ Inflorescence compound
2
1.
_ Inflorescence simple
15
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2.
_ Flowers not secund except sometimes insofar as the petals are exserted from the bracts on one side
3
2.
_ Flowers secund at anthesis and after; floral bracts often secund as well
12
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3.
_ Upper scape bracts equalling or exceeding the internodes
5
3.
_ Upper scape bracts shorter than the internodes
4
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4.
_ Sepals 35-50mm long; floral bracts humped below the apex; strongly rugose on drying; branches to 65-105cm long; leaf blades ligulate, acute, pale bluish green on top
4a
4.
_ Sepals 25mm long, floral bracts not humped; branches to 40cm long; leaf blades linear triangular, green
burle-marxii
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4a.
_ Leaf blades 43-45cm long, Branches 2-4, flowers 13-14cm long, petals 11cm
distractila
4a.
_ Leaf blades80-100cm long, Branches 8-9, flowers 9-11cm long, petals 8cm long
extensa
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5.
_ Primary bracts much shorter than the peduncle
6
5.
_ Primary bracts about equalling or exceeding the peduncle
7
5.
_ Primary bracts about equalling or shorter than the peduncle, Scape tortuous, primary bracts reddish-purple
tortuosa
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6.
_ Floral bracts very broadly acute to obtuse or truncate, usually ecarinate
10
6.
_ Floral bracts acute, carinate; rhachis strongly geniculate; floral bracts more than twice as long as the internodes
brasiliana
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7.
_ Floral bracts keeled (basal ones), 3.1 x 1.8cm; flowers 5-7 per branch; scape bracts broad ovate, green tipped red; inflorescence 45 x 20cm, subdense; leaves 65cm long; blades 7cm wide, green
nevaresii
7.
_ Floral bracts not keeled
8
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8.
_ Leaves with chalky covering
9
8.
_ Leaves without chalky covering; floral bracts 3cm long, yellow; flowers 13-16 per branch; scape bracts inflated, red; Inflorescence 20-30 x 20-30cm, subdense; leaves 45cm long, blades 7cm wide, sub-glabrous, green both sides
nahoumii
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9.
_ Branches erect to suberect, Floral bracts yellow, 3.5–4.0 x 4.5–5.3cm, flowers 11-26 per branch, inflorescence 45-100 x 25-50cm, leaves 1.3–1.6m long
patriae
9.
_ Branches horizontal to reflexed
9a
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9a.
_ Floral bracts green, 2 x 2cm; flowers ca 8 per branch; scape bracts greenish, red towards the base, farinose; inflorescence 40-65 x 26cm, sublax; leaves 100cm long; blade 7cm wide, chalky
odorata
9a.
_ Floral bracts yellow
9b
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9b.
_ Leaf blades not covered by a dense layer of white scales, inflo 74-96 x 60-75cm, primary bracts shorter than stipes, branches 20(top)-36cm long, flowers 13.5-15.5 cm long, petals pale yellow
lurida
9b.
_ Leaf blades covered by a dense layer of white scales, inflo 41 x 34cm, primary bracts about equalling the stipes, branches 16 (top)-20cm long , flowers 10-10.5 cm long, petals bright golden yellow
heloisae
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10.
_ Branches to 65cm long, 30cm peduncle, flowers lax; floral bracts 4cm long, suborbicular, strongly gibbous, humped below apex, ecarinate; flowers to 8cm long; rhachis geniculate
extensa
10.
_ Branches to 60cm long, 35-40cm peduncle, flowers densely arranged; floral bracts 4.8 x 3.3cm, ecarinate; rhachis straight; petals white
roberto-kautskyi
10.
_ Branches to 40cm long, spreading and ascending towards apex, to 22cm peduncle, flowers ca. lax, floral bracts 3.5cm long, suborbicular, green and wine coloured edges, carinate, flowers 10cm long, rhachis geniculate
turgida
10.
_ Branches to 30cm long
11
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11.
_ Floral bracts broad ovate, 27 x 25mm basal ones carinate; rhachis geniculate; peduncle 5-8cm long; inflorescence 30-40cm wide; branches 12-25cm long; petals yellow
geniculata
11.
_ Floral bracts suborbicular, 30-40 x 30-37mm, ecarinate, rhachis slightly flexuous; inflorescence 50-60cm wide; branches 20-30cm long; petals white
glaziouana
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12.
_ Flowers upward secund; branches spreading, many; sepals 35-45mm long
13
12.
_ Flowers downward secund; branches with naked sterile bases, 5-8 flowered; leaves attenuate at apex; sepals much exceeding the floral bracts
duarteana
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13.
_ Rhachis strongly geniculate; only a few flowers secund; primary bracts exceeding internodes; floral bracts green; petals yellow
brasiliana
13.
_ Rhachis strongly geniculate; only a few flowers secund; primary bracts less than internodes; floral bracts purplish; petals light brownish
vinicolor
13.
_ Rhachis merely flexuous; all of the flowers secund
14
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14.
_ Primary bracts reddish; floral bracts reddish, 2.5cm long to about half of sepal; petal yellow turning white when fully open ; flowering 3–5m
imperialis
14.
_ Primary bracts green; floral bracts yellow 3.5 x 3cm; petals yellow; flowering to 1.8m
edmundoi
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15.
_ Plant flowering to 1.4m tall; inflorescence over 30cm long; no petal appendages; petals yellow/green
hatschbachii
15.
_ Plant flowering to 70cm tall; inflorescence to 16cm long; with petal appendages
16
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16.
_ Floral bracts exceeding the sepals; inflorescence lax and distichous; rhachis flexuous; petals yellow
benzingii
16.
_ Floral bracts about equalling the sepals; inflorescence distichous, slowly secund at anthesis; rhachis geniculate; petals yellow
farneyi


Updated 09/04/08