| 1 |
Some or all ocreae foliaceous and green distally |
|
(2) |
| + |
All ocreae chartaceous and hyaline, tan, brown, or reddish brown throughout, never foliaceous and green distally |
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(3) |
| |
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| 2 (1) |
Plants annual; rhizomes and stolons absent; leaf blades ovate, 3-17 cm wide |
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22 Persicaria orientalis |
| + |
Plants perennial; rhizomes or stolons usually present; leaf blades ovate-lanceolate to elliptic or oblong-lanceolate, 1-6(-8) cm wide |
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11 Persicaria amphibia (in part) |
| |
|
|
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| 3 (1) |
Perianths glandular-punctate |
|
(4) |
| + |
Perianths not glandular-punctate |
|
(9) |
| |
|
|
|
| 4 (3) |
Achenes minutely roughened, dull; axillary inflorescences sometimes enclosed in ocreae |
|
21 Persicaria hydropiper |
| + |
Achenes smooth, shiny; inflorescences never enclosed in ocreae |
|
(5) |
| |
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|
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| 5 (4) |
Outer tepals with anchor-shaped veins; achenes discoid |
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20 Persicaria lapathifolia (in part) |
| + |
Outer tepals without anchor-shaped veins; achenes 3-gonous or biconvex |
|
(6) |
| |
|
|
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| 6 (5) |
Ocreae margins eciliate; achenes biconvex; styles 2 |
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14 Persicaria glabra (in part) |
| + |
Ocreae margins ciliate with bristles 2-12 mm; achenes usually 3-gonous, rarely biconvex; styles 2-3 |
|
(7) |
| |
|
|
|
| 7 (6) |
Punctae confined to bases of perianths and sometimes on inner tepals |
|
13 Persicaria hydropiperoides (in part) |
| + |
Punctae ± uniformly distributed over perianths |
|
(8) |
| |
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|
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| 8 (7) |
Inflorescences interrupted; ocreolae mostly not overlapping, margins mostly ciliate with hairs to 2 mm; leaf blades 0.6-2.4 cm wide |
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15 Persicaria punctata |
| + |
Inflorescences uninterrupted; ocreolae usually overlapping, margins mostly eciliate or proximal sometimes with hairs to 1 mm; leaf blades 2-4.5 cm wide |
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12 Persicaria robustior |
| |
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| 9 (3) |
Peduncles stipitate-glandular |
|
(10) |
| + |
Peduncles not stipitate-glandular |
|
(14) |
| |
|
|
|
| 10 (9) |
Plants perennial; rhizomes or stolons usually present; inflorescences terminal |
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11 Persicaria amphibia (in part) |
| + |
Plants annual; rhizomes and stolons absent; inflorescences terminal and axillary |
|
(11) |
| |
|
|
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| 11 (10) |
Stems hirsute proximally; margins of ocreae ciliate with bristles 2-7 mm |
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23 Persicaria careyi |
| + |
Stems glabrous proximally; margins of ocreae eciliate or ciliate with bristles less than 1 mm |
|
(12) |
| |
|
|
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| 12 (11) |
Outer tepals with anchor-shaped veins; tepals 4(-5); inflorescences mostly arching or nodding |
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20 Persicaria lapathifolia (in part) |
| + |
Outer tepals without anchor-shaped veins; tepals 5; inflorescences erect or, rarely, nodding |
|
(13) |
| |
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|
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| 13 (12) |
Flowers homostylous; achenes without central hump on 1 side |
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18 Persicaria pensylvanica (in part) |
| + |
Flowers heterostylous; achenes usually with central hump on 1 side |
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19 Persicaria bicornis (in part) |
| |
|
|
|
| 14 (9) |
Plants perennial; rhizomes or stolons usually present |
|
(15) |
| + |
Plants annual; rhizomes and stolons absent |
|
(19) |
| |
|
|
|
| 15 (14) |
Achenes biconvex; styles 2 |
|
(16) |
| + |
Achenes 3-gonous; styles 3 |
|
(17) |
| |
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|
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| 16 (15) |
Perianth greenish white or white to pink; surfaces of ocreae glabrous, usually obscurely glandular-punctate |
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14 Persicaria glabra (in part) |
| + |
Perianth roseate to red; surfaces of ocreae glabrous or appressed-pubescent to hirsute, not glandular-punctate |
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11 Persicaria amphibia (in part) |
| |
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|
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| 17 (15) |
Proximal part of ocreae strigose, or ocreae glabrous |
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13 Persicaria hydropiperoides (in part) |
| + |
Proximal part of ocreae hirsute, or strigose and with loosely ascending to spreading hairs at least proximally |
|
(18) |
| |
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| 18 (17) |
Bases of leaf blades rounded to cordate; stems brownish-hirsute on internodes |
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16 Persicaria hirsuta |
| + |
Bases of leaf blades tapered to truncate; stems glabrous or loosely appressed- to spreading-hirsute near nodes |
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17 Persicaria setacea |
| |
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| 19 (14) |
Margins of ocreae without bristles or with bristles to 1 mm; ocreolae mostly overlapping; achenes discoid, rarely 3-gonous |
|
(20) |
| + |
Margins of ocreae ciliate with bristles (0.2-)1-12 mm, if bristles less than 1 mm then ocreolae not overlapping; achenes discoid, biconvex, or 3-gonous |
|
(22) |
| |
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| 20 (19) |
Outer tepals with anchor-shaped veins; tepals 4(-5); inflorescences mostly arching or nodding |
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20 Persicaria lapathifolia (in part) |
| + |
Outer tepals without anchor-shaped veins; tepals 5; inflorescences mostly erect, rarely nodding |
|
(21) |
| |
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| 21 (20) |
Flowers homostylous; achenes without central hump on 1 side |
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18 Persicaria pensylvanica (in part) |
| + |
Flowers heterostylous; achenes usually with central hump on 1 side |
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19 Persicaria bicornis (in part) |
| |
|
|
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| 22 (19) |
Inflorescences not dense; ocreolae not overlapping proximally, usually overlapping distally; leaf blades linear to linear-lanceolate |
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25 Persicaria minor |
| + |
Inflorescences dense; ocreolae mostly overlapping; leaf blades narrowly ovate or ovate-lanceolate to linear-lanceolate |
|
(23) |
| |
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| 23 (22) |
Bristles of ocreolae 0.2-1.3(-2) mm; achenes discoid, biconvex, or 3-gonous; styles 2-3 |
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26 Persicaria maculosa |
| + |
Bristles of ocreolae (0.5-)1-4(-6) mm; achenes 3-gonous; styles 3 |
|
24 Persicaria longiseta |
