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Silene
See list of 15 species in this genusThe genus Silene has seen numerous revisions to its circumscription. Definitions have varied, from a very inclusive Silene (e.g., Morton 2005b) to a narrowly defined Silene (e.g., Oxelman et al. 2000). The latter is followed here as it was based on morphology and DNA sequence data interpreted in a phylogenetic fashion, and the entities (i.e., genera) they proposed are very distinguishable ( Atocion, Eudianthe, Lychnis, Silene, and Viscaria in the New England flora). Reference: Morton (2005b).
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1a. Plants dioecious, the carpellate flowers with 5 styles and the staminate flowers with 1 style; capsules dehiscing by 5 valves, each valve usually splitting again
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2a. Flowers with white petals, fragrant, opening in the evening; leaf blades oblong-lanceolate to elliptic, 6–30 mm wide; carpophore 1–2 mm long; capsules ovoid, the valves erect or slightly recurved after dehiscence; seeds coarsely tuberculate
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2b. Flowers with red petals, inodorous, opening during the day; leaf blades ovate to elliptic, 10–50 mm wide; carpophore absent; capsules broad-ovoid to subglobose, the valves recurved after dehiscence; seeds densely and uniformly papillose
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1b. Plants synoecious, the flowers with 3 (rarely 4) styles; capsules dehiscing by 3 valves that eventually split again (rarely 4 valves that split again)
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3a. Plants matted, pulvinate, alpine, 3–6 cm tall [Fig. 569]; flowers solitary at the tips of branches; petals purple
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3b. Plants upright, simple or branched, but not matted, of low-elevation habitats, 8–150 cm tall; flowers solitary in the axils of leaves or in terminal cymes; petals white to pink to red (rarely purple)
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4a. Flowers solitary on peduncles from the axils of the upper leaves
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4b. Flowers in a terminal cyme
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5a. Inflorescence a monochasial cyme, appearing as a secund raceme [Fig. 571]
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6a. Axis of the inflorescence commonly forking; petals lobed to below the middle; stems coarse, 20–100 cm tall
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6b. Axis of the inflorescence usually simple; petals retuse or lobed nearly to the middle; stems shorter, 15–45 cm tall
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7a. Calyx 7–10 mm long in fruit, pubescent with both short, glandular hairs and longer eglandular hairs, the lobes acute at the apex; petals entire to retuse at the apex; flowers erect to ascending; stems erect
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7b. Calyx 12–18 mm long in fruit, pubescent with only short, glandular hairs, the lobes obtuse at the apex; petals lobed nearly to the middle; flowers divergent or nodding; stems procumbent to ascending
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5b. Inflorescence a dichasial cyme (note: the cyme sometimes panicle-like) [Fig. 573]
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8a. Calyx glabrous (or sometimes minutely pubescent near the base)
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9a. Stems glutinous below the nodes; calyx fitting rather tightly over the capsule, 10-nerved; plants annual
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9b. Stems not glutinous; calyx inflated, fitting loosely over the body of the capsule, 20-nerved; plants biennial or perennial (rarely annual in S. csereii)
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10a. Calyx with 20 obscure veins of equal length connected by many, smaller, anastomosing veins, 12–18 mm long in fruit; filaments pale for much of their length, sometimes purple near the apex; seeds ± black, 1–1.5 mm long, finely tuberculate
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10b. Calyx with 10 long veins and 10 short veins, with few or no anastomosing veins, 9–13 mm long in fruit; filaments dark purple; seeds 0.6–1 mm long, gray-brown, with concentric rings of papillae
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8b. Calyx pubescent, especially on the nerves [Fig. 572]
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11a. Stem leaves mostly in whorls of 4 (the lower and upper nodes may have opposite leaves); petals fimbriately lobed into 8–12 apical segments
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11b. Stem leaves opposite throughout; petals entire, retuse, or notched at the apex
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12a. Petals entire or merely retuse at the apex; calyx lobes rounded to obtuse at apex; plants 8–20 (–25) cm tall; seeds 1.3–1.5 mm long, papillose
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12b. Petals with a prominent notch, creating a 2-lobed apex; calyx lobes acute to attenuate at apex; plants (15–) 20–80 cm tall; seeds 0.6–1 mm long, tuberculate
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13a. Calyx with ca. 30 longitudinal nerves [Fig. 570], umbilicate at the base in fruit
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13b. Calyx with 10 nerves, not umbilicate at base
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14a. Calyx 15–24 mm long in flower, becoming 25–30 (–40) mm long in fruit; petals pink on the adaxial surface, yellow on the abaxial surface, opening at night, with auricles 1–1.5 mm long; leaf blades lanceolate to narrow-ovate, 20–40 mm wide; plants not clumped, annual
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14b. Calyx 7–10 mm long; petals white or pink, open during the day, with inconspicuous auricles; leaf blades narrow-lanceolate to oblanceolate, 5–15 mm wide; plants subcespitose, perennial
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