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| 1 Inflorescence an involucrate head subtended by phyllaries, the heads solitary or many and variously arrayed in secondary inflorescences, the ovary inferior, the corolla connate and tubular at least basally, the calyx absent, the stamens 5, the fruit a cypsela |
| 1 Inflorescence, flower, and fruit structure various, but not with the combination of features as above (sometimes the flowers in a head subtended by bracts, e.g. Eryngium in APIACEAE, but then with other features differing, such as stamens 4, or green calyx present, or petals separate, or fruit a schizocarp of mericarps, etc.). |
| ..2 Basal leaves 2-lobed, pinnately lobed, or palmately lobed (not considering cordate, hastate, or auriculate leaf bases as “lobed”). |
| ....3 Basal leaves 2-lobed, hinged between the lobes, each lobe with stiff, marginal, eyelash-like bristles; [Coastal Plain of NC and SC, rarely planted and weakly naturalized elsewhere] |
| ....3 Basal leaves 3-many-lobed, palmately or pinnately; [collectively widespread]. |
| ......4 Leaf lobing pinnate. |
| ........5 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate |
| ........5 Gynoecium of a single pistil (with 2, rarely more, carpels); fruit simple. |
| ..........6 Stamens many; sepals 2, petals 4; fresh plants with yellow, orange, or white milky juice |
| ..........6 Stamens 4, 5, or 6; sepals 4 or 5; petals 4 or 5. |
| ............ 7 Petals 4, distinct; stamens 6 |
| ............ 7 Petals 5, fused; stamens 2, 4, or 5. |
| ............ ..8 Corolla radially symmetrical; stamens 5 |
| ............ ..8 Corolla 2-lipped, bilaterally symmetrical or asymmetrical; stamens 2 or 4. |
| ............ ....9 Corolla lobes not twisted, the flower bilaterally symmestrical; stamens 2 |
| ............ ....9 Corolla lobes twisted so as to make the flower asymmetrical; stamens 4 |
| ......4 Leaf lobing palmate. |
| ............ ......10 Petiole attachment peltate. |
| ............ ........11 Leaves < 10 cm in diameter |
| ............ ........11 Leaves > 15 cm in diameter |
| ............ ......10 Petiole attachment marginal. |
| ............ ..........12 Ovary inferior. |
| ............ ............ 13 Petals 4; stamens 8; fruit a capsule |
| ............ ............ 13 Petals 5; stamens 5; fruit a schizocarp of 2 mericarps. |
| ............ ............ ..14 Fruit tuberculate; leaves 3-lobed |
| ............ ............ ..14 Fruit smooth; leaves with 5 or more lobes |
| ............ ..........12 Ovary superior, or half-inferior by fusion of a hypanthium a part of the way up the ovary wall. |
| ............ ............ ....15 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate. |
| ............ ............ ......16 Perianth of 5 green sepals and 5 colored petals. |
| ............ ............ ........17 Carpels partly fused, arrayed in a ring of 10-20 |
| ............ ............ ........17 Carpels separate, spiral, many |
| ............ ............ ......16 Perianth of a single whorl of 3-12 petaloid sepals (the petals absent or small and rudimentary). |
| ............ ............ ..........18 Leaves 2, the single flower terminal and associated with the upper leaf; fruit an aggregate of berries |
| ............ ............ ..........18 Leaves normally > 2, flowers not as above; fruit an aggregate of achenes, utricles, or follicles |
| ............ ............ ....15 Gynoecium of a single pistil (with 1-5 carpels); fruit simple. |
| ............ ............ ............ 19 Hypanthium present, partially fused or not fused to the pistil; ovary partially inferior to superior |
| ............ ............ ............ 19 Hypanthium absent; ovary superior. |
| ............ ............ ............ ..20 Petals connate at base; leaves sharply toothed |
| ............ ............ ............ ..20 Petals distinct; leaves with rounded lobes or teeth. |
| ............ ............ ............ ....21 Corolla radially symmetrical; petals 8-12; capsule fusiform, narrowed to both ends, > 5× as long as wide |
| ............ ............ ............ ....21 Corolla bilaterally symmetrical; petals 5; capsule ovoid, < 2× as long as wide |
| ..2 Basal leaves not lobed, at most serrate or crenate (and sometimes also cordate, hastate, auriculate, or peltate at the base). |
| ............ ............ ............ ......22 Basal leaves petiolate, the blade with a cordate, hastate, auriculate, or peltate base. |
| ............ ............ ............ ........23 Leaf margins entire. |
| ............ ............ ............ ..........24 Inflorescence a terminal and/or axillary raceme, panicle, or cyme of many small flowers; fruit an achene; perianth uniseriate, of 0, 4-5, or 6 tepals. |
| ............ ............ ............ ............ 25 Flowers unisexual; staminate flowers 4-5 tepals, pistillate flowers lacking a perianth |
| ............ ............ ............ ............ 25 Flowers bisexual; flowers with 6 tepals |
| ............ ............ ............ ..........24 Inflorescence either a terminal spike, or a 1-7-flowered terminal cyme, or of a solitary axillary or terminal flower; fruit various; perianth biseriate (of differentiated sepals and petals (except uniseriate, of 3 fused sepals in ARISTOLOCHIACEAE). |
| ............ ............ ............ ............ ..26 Flowers bilaterally symmetrical; inflorescence a terminal spike (with > 20 flowers); petals 4, usually scarious, transparent; sepals 4, green; stamens 4 |
| ............ ............ ............ ............ ..26 Flowers radially symmetrical; inflorescence either of a solitary flower or of a 1-7-flowered terminal cyme; petals 5, 8-12, or 0; sepals 5 (green), 3 (brown), or 5-9 (yellow); stamens 5, 12, or many. |
| ............ ............ ............ ............ ....27 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate of achenes or follicles; flowers bright yellow, either of 5-9 distinct petaloid sepals, or of 8-12 distinct petals subtended by 3-4 green distinct sepals |
| ............ ............ ............ ............ ....27 Gynoecium either of a single pistil with 6 carpels or of a single pistil with 4 carpels or of 2 nearly separate carpels; fruit a simple capsule (or deeply 2-lobed); flowers white, brown, or greenish, either of 5 fused or distinct white petals and 5 fused or distinct green sepals, or of 3 fused brown or greenish petaloid sepals. |
| ............ ............ ............ ............ ......28 Flowers brown or green, of 3 fused brown or greenish petaloid sepals (and 0 petals); carpels 6; stamens 12; leaves 4-10 cm wide |
| ............ ............ ............ ............ ......28 Flowers white, of 5 white or whitish petals and 5 green sepals; carpels 2; stamens 5; leaves 1-12 (-15) cm wide |
| ............ ............ ............ ............ ........29 Petals separate; sepals separate; plant glabrous |
| ............ ............ ............ ............ ........29 Petals fused; sepals fused; carpels 2; plant pubescent. |
| ............ ............ ............ ............ ..........30 {XXXX}; [common, widespread in our area] |
| ............ ............ ............ ............ ..........30 {YYYY}; [rare alien] |
| ............ ............ ............ ........23 Leaf margins crenate, serrate, or incised. |
| ............ ............ ............ ............ ............ 31 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate; perianth of 5 green sepals and 5 colored petals. |
| ............ ............ ............ ............ ............ ..32 Carpels 10-20, partly fused, arrayed in a ring; petals white, pink, red, or purplish |
| ............ ............ ............ ............ ............ ..32 Carpels many, separate, spiral; petals yellow or white. |
| ............ ............ ............ ............ ............ ....33 Flowers lacking a hypanthium; fruit an aggregate of achenes or aggregate of follicles |
| ............ ............ ............ ............ ............ ....33 Flowers with a hypanthium; fruit an aggregate of drupelets or aggregate of achenes |
| ............ ............ ............ ............ ............ 31 Gynoecium of a single pistil (with 1-5 carpels); fruit simple. |
| ............ ............ ............ ............ ............ ......34 Flowers bilaterally symmetrical; inflorescence of a solitary flower; fruit a 3-locular capsule |
| ............ ............ ............ ............ ............ ......34 Flowers radially symmetrical; inflorescence an umbel (or composite of umbelliform units, or a terminal panicle. |
| ............ ............ ............ ............ ............ ........35 Ovary superior; inflorescence a terminal panicle or terminal raceme. |
| ............ ............ ............ ............ ............ ..........36 Inflorescence a terminal raceme; perianth of 4 green sepals and 4 white petals; fruit a silique/silicle; fresh foliage in spring and summer with a strong garlic odor; larger leaves < 10 cm in diameter |
| ............ ............ ............ ............ ............ ..........36 Inflorescence a terminal panicle; perianth of 6 cream-colored petaloid sepals; fruit a winged achene; fresh foliage lacking a garlic odor; larger leaves typically > 30 cm in diameter |
| ............ ............ ............ ............ ............ ........35 Ovary inferior; inflorescence an umbel (or a composite of umbellate units); fruit a schizocarp of mericarps. |
| ............ ............ ............ ............ ............ ............ 37 Petiole attachment peltate |
| ............ ............ ............ ............ ............ ............ 37 Petiole attachment marginal (the blade cleft to the petiole. |
| ............ ............ ............ ............ ............ ............ ..38 Leaf blades longer than wide, sharply V-cleft at the base and otherwise shallowly denticulate |
| ............ ............ ............ ............ ............ ............ ..38 Leaf blades as broad or broader than long, cleft at the base and also irregularly serrate or crenate around the margin |
| ............ ............ ............ ......22 Basal leaves petiolate or not, with a truncate, rounded, or cuneate leaf base. |
| ............ ............ ............ ............ ............ ............ ....39 Leaves tubular, with a sutured ventral flange, erect or reclining, adapted as a pitfall for insects (flat, phyllodial leaves sometimes present as well, common in the winter in some species, such as S. oreophila) |
| ............ ............ ............ ............ ............ ............ ....39 Leaves flat, not sutured into a tubular shape. |
| ............ ............ ............ ............ ............ ............ ......40 Stem leaves opposite; perianth 5-merous, at least the corolla bilaterally symmetrical (barely so in VALERIANACEAE), or the parts curved so as to be asymmetrical (Pedicularis in OROBANCHACEAE); stamens 2, 3, or 4. |
| ............ ............ ............ ............ ............ ............ ........41 Ovary inferior; stamens 3 |
| ............ ............ ............ ............ ............ ............ ........41 Ovary superior; stamens 2 or 4. |
| ............ ............ ............ ............ ............ ............ ..........42 Corolla narrowly tubular, the five lobes flaring at nearly 90 degrees and nearly radially symmetrical |
| ............ ............ ............ ............ ............ ............ ..........42 Corolla distinctly 2-lipped (with prominently large upper and lower corolla lobes) or hooded (the upper lip hood-like), distinctly bilaterally symmetrical, or the lobes twisted so as to make the corolla asymmetrical. |
| ............ ............ ............ ............ ............ ............ ............ 43 Corolla yellow, the upper lip often slightly to strongly maroon, hooded but the corolla lobes twisted so as to make the flower asymmetrical |
| ............ ............ ............ ............ ............ ............ ............ 43 Corolla white, lavender, or blue, 2-lipped and bilaterally symmetrical. |
| ............ ............ ............ ............ ............ ............ ............ ..44 Sepals separate to the base or nearly so, not forming a tube |
| ............ ............ ............ ............ ............ ............ ............ ..44 Sepals connate for at least 0.3× their length to form a tube |
| ............ ............ ............ ............ ............ ............ ......40 Stem leaves alternate; perianth radially symmetrical (less commonly bilaterally symmetrical); stamens 5, 6-8, 9, 10 (rarely 4). |
| ............ ............ ............ ............ ............ ............ ............ ....45 Ovary inferior (or half-inferior in Samolus). |
| ............ ............ ............ ............ ............ ............ ............ ......46 Perianth 4-merous; stamens 8 |
| ............ ............ ............ ............ ............ ............ ............ ......46 Perianth 5-merous; stamens 5. |
| ............ ............ ............ ............ ............ ............ ............ ........47 Inflorescence an umbel; fruit a schizocarp of 2 mericarps |
| ............ ............ ............ ............ ............ ............ ............ ........47 Inflorescence an axillary or terminal raceme; fruit a capsule |
| ............ ............ ............ ............ ............ ............ ............ ....45 Ovary superior. |
| ............ ............ ............ ............ ............ ............ ............ ..........48 Pistils many, each with a single carpel; fruit an aggregate of achenes |
| ............ ............ ............ ............ ............ ............ ............ ..........48 Pistil 1, with 1-5 carpels; fruit simple (a legume, silique/silicle, capsule, utricle, or schizocarp of 4 nutlets). |
| ............ ............ ............ ............ ............ ............ ............ ............ 49 Corolla bilaterally symmetrical (barely so in Limosella in SCROPHULARIACEAE); stamens 2, 4, 6, 8, or 10. |
| ............ ............ ............ ............ ............ ............ ............ ............ ..50 Stamens 6-8 or 10. |
| ............ ............ ............ ............ ............ ............ ............ ............ ....51 Petals separate; stamens 10 |
| ............ ............ ............ ............ ............ ............ ............ ............ ....51 Petals fused; stamens 10 or 6-8. |
| ............ ............ ............ ............ ............ ............ ............ ............ ......52 Stamens 10, monadelphous |
| ............ ............ ............ ............ ............ ............ ............ ............ ......52 Stamens 6-8, epipetalous |
| ............ ............ ............ ............ ............ ............ ............ ............ ..50 Stamens 2 or 4. |
............ ............ ............ ............ ............ ............ ............ ............ ........53 Stamens 2 |
| ............ ............ ............ ............ ............ ............ ............ ............ ........53 Stamens 4. |
| ............ ............ ............ ............ ............ ............ ............ ............ ..........54 [plants of coastal wetlands] |
| ............ ............ ............ ............ ............ ............ ............ ............ ..........54 [plants of uplands or inland seeps or fens] |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ 55 Flowers (and subtending bracts) red or yellow |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ 55 Flowers purple, blue, or lavender |
| ............ ............ ............ ............ ............ ............ ............ ............ 49 Corolla radially symmetrical; stamens 5, 10, 4-6, or 9. |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ..56 Perianth of 6 tepals; stamens 4-6 or 9; carpels 3 |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ..56 Perianth of green sepals and more brightly colored petals; stamens 5 or 10; carpels 2, 3, 4, or 5. |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ....57 Leaves covered with sticky, gland-tipped hairs (often red), as flypaper traps for insects |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ....57 Leaves lacking sticky gland-tipped hairs. |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ......58 Fruit a schizocarp of 4 nutlets (ovary obviously 4-lobed in flower) |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ......58 Fruit a capsule or silique/silicle (or utricle in Limonium in PLUMBAGINACEAE). |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ........59 Inflorescence of a solitary, terminal flower; carpels 2-3 (-4). |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ..........60 Corolla with a long tube and flaring corolla lobes (united > ½ its length) |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ..........60 Corolla of separate petals or united only for a short length (< ¼ its length). |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 61 Leaves serrate |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 61 Leaves entire |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ........59 Inflorescence of several to many flowers; carpels 5 (3 in Galax in DIAPENSIACEAE). |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ..62 Inflorescence an umbel; petals recurved, pink to almost white |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ..62 Inflorescence a raceme or panicle. |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ....63 Fruit a silique/silicle; petals 4; stamens 6 |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ....63 Fruit either a capsule or a utricle; petals 5; stamens 5 or 10. |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ......64 Inflorescence a somewhat to very diffuse panicle, with 3 or more orders of branching, not giving at all the impression that the overall inflorescence is made of racemose units. |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ........65 Leaves entire; stamens 5; [plants of tidal marshes] |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ........65 Leaves serrate or crenate; stamens 10; [plants of various habitats, especially rock outcrops and bottomland forests and streambanks, never in tidal marshes] |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ......64 Inflorescence either a single terminal raceme (sometimes spike-like), or of 1 to several terminal and axillary racemes (these sometimes combined into a diffuse panicle, but one whose structure is clearly made up of many racemes). |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ..........66 Inflorescence of 1-several terminal and axillary racemes, the plant typically well-branched, especially from the base; stamens 5 |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ..........66 Inflorescence of a single, terminal raceme, the plant unbranched; stamens 10 (or 5, with 5 staminodes) |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 67 Inflorescence spike-like, the flowers many (> 40), barely pedicelled; capsule 3-locular |
| ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 67 Inflorescence a raceme, the flowers fewer (< 20) and distinctly pedicelled; capsule 5-locular |