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Caryophyllaceae
See list of 28 genera in this familyReference: Mitchell (1993).
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1a. Sepals distinct or essentially so (appearing connate in Scleranthus, but the tube actually a hypanthium) [Figs. 564,565,578]; ovary sessile; petals without a prominent, narrow, basal portion (i.e., lacking a claw or the claw obscure)
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3a. Leaves alternate (rarely some subopposite); gynoecium with 3 sessile stigmas
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3b. Leaves opposite or whorled [Fig. 561]; gynoecium with 2–5 stigmas (with 3 stigmas in Polycarpon and Spergularia but these elevated on styles)
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4a. Flowers without petals [Fig. 565]; gynoecium with a single ovule; ovary maturing as a utricle
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5a. Sepals white, spongy, each with a prominent awn
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5b. Sepals ± green (but white-scarious at the margin in Paronychia, the actual color may be partly obscured by white or gray hairs on the abaxial surface), not spongy, with or without awns
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6a. Stipules with entire margins, (0.5–) 1–8 mm long; calyx 1–4 mm long, the lobes white-scarious at the margins
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6b. Stipules with fringed margins [Fig. 561], 0.5–1 (–1.5) mm long; calyx 0.5–1.5 mm long, the lobes green
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4b. Flowers with white or pink to red-purple petals (but these sometimes caducous in Polycarpon); gynoecium with many ovules; ovary maturing as a capsule
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7a. Flowers with a single style that is obscurely lobed near the apex; leaf blades elliptic to ovate or obovate; valves of capsules twisted after dehiscence and forming a tube
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7b. Flowers with 3–5 styles; leaf blades linear to broad-linear; valves of capsules spreading to recurved but not twisted into a tube
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8a. Leaves clustered at the nodes in 2 sets of 6–8, appearing whorled, with small stipules 0.5–1 (–1.5) mm long; flowers usually with 5 styles; capsules with usually 5 valves
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8b. Leaves opposite (with axillary fascicles in S. rubra), with stipules 1–5 mm long; flowers usually with 3 styles; capsules with usually 3 valves
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2b. Leaves without stipules
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9a. Flowers perigynous (i.e., with a cupuliform hypanthium) [Fig. 568]; fruit a 1-seeded utricle; perianth sepaloid, composed of only sepals that have a narrow, scarious border
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9b. Flowers hypogynous or essentially so; fruit a many-seeded capsule; perianth in part petaloid, composed of both sepals and petals (petals absent and, therefore, the perianth sepaloid in some Sagina and Stellaria)
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10a. Perianth monochlamydeous, only the sepals present
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11a. Flowers with 3 styles; capsule dehiscing by 6 valves; leaves linear-oblong to elliptic, 1.5–6 (–10) mm wide (in part)
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11b. Flowers with 4 or 5 styles; capsule dehiscing by 4 or 5 valves; leaves linear-subulate, up to 1 mm wide (in part)
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12a. Petals deeply notched, in some Stellaria so deeply as to appear as 2 distinct, but proximate, petals [Figs. 557,579]
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13a. Gynoecium with 3 styles; capsules dehiscing by 6 valves (in part)
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13b. Gynoecium with 4 or 5 styles [Fig. 557]; capsules dehiscing by 5 valves or by 8 or 10 apical teeth
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14a. Capsules cylindric, dehiscing by 8 or 10 apical teeth; vegetative leaf blades 1–15 mm wide
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14b. Capsules ovoid, dehiscing by 5 valves, each valve notched or shortly bifid at the apex; vegetative leaf blades 10–40 mm wide
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15a. Plants fleshy; seeds 3–5 mm long; petals and stamens inserted on a conspicuous, 10-lobed disk
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15b. Plants not fleshy; seeds 0.4–1.4 mm long; staminal disk inconspicuous
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16a. Flowers with 4 or 5 styles [Fig. 567]; capsules dehiscing by 4 or 5 valves (in part)
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16b. Flowers with 3 styles; capsules dehiscing by 3 or 6 valves
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17a. Inflorescence an umbel with 3–15 flowers; petals minutely erose at apex
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17b. Inflorescence a cyme or a solitary flower; petals not erose at apex
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18a. Seeds 1–1.6 mm long, strophiolate; plants rhizomatous perennials, the stems not tufted
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18b. Seeds 0.4–0.8 mm long, not strophiolate; plants annuals or perennials, the stems tufted
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19a. Capsules dehiscing by 6 valves; leaf blades lanceolate to ovate, 3–5 mm wide
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19b. Capsules dehiscing by 3 valves; leaf blades linear to narrow-oblanceolate, 0.3–0.8 mm wide
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1b. Sepals connate in the basal portion [Figs. 570,572]; ovary stipitate; petals with a prominent, narrow, basal portion (i.e., possessing a claw)
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20a. Flowers with 5 (rarely 4) styles or 1 style in staminate individuals of dioecious Silene; capsules dehiscing by 5 or 10 valves or teeth (or dehiscing by 8 valves in 4-styled flowers)
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21a. Style conspicuously pubescent; calyx lobes 20–40 mm long, much longer than the connate portion; petals lacking both auricles and appendages at the junction of the claw and blade
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21b. Style glabrous; calyx lobes 2.5–9 mm long, much shorter than the connate portion; petals commonly with auricles and/or appendages at the junction of the claw and blade
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22a. Plants dioecious (i.e., with unisexual flowers), the staminate flowers with a single, undivided style; capsules dehiscing by 5 valves that eventually split again (in part)
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22b. Plants synoecious (i.e., with bisexual flowers); capsules dehiscing by 5 valves or 5 bifid teeth
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23a. Plants annual; calyx 15–28 mm long; carpophores (5–) 7–12 mm long; leaf blades linear to narrow-lanceolate
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23b. Plants perennial; calyx 6–17 mm long; carpophores 0–6 mm long; leaf blades narrow-lanceolate to narrow-oblong or ovate
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24a. Style bases persistent in fruit and reflexed; capsule unilocular, septicidally dehiscent, each valve lacking a distinct midline; petals 2- or 4-lobed, the lobes varying from short and separated by a shallow sinus to elongate and separated by a deep sinus [Fig. 563]
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24b. Style bases not persistent in fruit; capsule 5-locular in the basal portion, loculicidally dehiscent, each valve with a distinct midline, sometimes further splitting on this line; petals ± entire at the apex
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20b. Flowers with 2 or 3 styles; capsules dehiscing by 4 or 6 valves
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26a. Calyx with 5 principal nerves (with an additional 10 fine nerves in 1 species), prominently scarious between the 5 principal nerves
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26b. Calyx 20- to 40-nerved [Fig. 559], without scarious regions between the nerves
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25b. Calyx not subtended by bracts, 5- to 30-nerved; seeds orbicular to reniform
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27a. Flowers with 3 styles; capsules dehiscing by 6 valves
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28a. Capsules borne on a carpophore 7–8 mm long [Fig. 555]; pedicels 1–5 mm long; stem and calyx glabrous
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28b. Capsules borne on a carpophore as long as 6 mm (5–8 mm long in S. caroliniana); pedicels (2–) 5–50 mm long; commonly either the stem and/or the calyx pubescent, but both glabrous in a few species (in part)
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27b. Flowers with usually 2 styles; capsules dehiscing by 4 valves
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29a. Adaxial surface of petals with a subulate appendage at the junction of the claw and blade; calyx with 20, often inconspicuous, nerves
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29b. Petals without an appendage; calyx with 5 nerves
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30a. Petals 18–22 mm long; seeds globose; calyx nerved with stout ribs, these becoming wing angles in fruit, not at all scarious
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30b. Petals 2–15 mm long; seeds subreniform; calyx merely nerved, without prominent wing angles in fruit, evidently scarious between its green nerves [Fig. 560]
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Each photo represents one genus in this family.