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1 Shrub or vine; leaves compound (or sometimes some to most of them simple in Clematis). | |
2 Leaves alternate, clustered together at the top of the usually unbranched, erect stem; sepals 5, maroon, 2-5 mm long; wood yellow; [subfamily Coptidoideae] | |
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1 Flowers bilaterally symmetrical, the upper sepal hooded or spurred; [tribe Delphinieae]. | |
1 Flowers radially symmetrical, no perianth parts spurred or hooded (except the 5 sepals spurred in Myosurus). | |
3 Petals present, white or yellow, larger and more conspicuous than the sepals; sepals present, green; [in other words, with a second, green, less conspicuous perianth whorl below the largest and colored perianth whorl; note that some Anemone have a calyx-like involucre of 3 bracts subtending each flower]; [tribe Ranunculeae]. | |
4 Basal leaves linear to linear-spatulate, mostly 4-8 cm long, 1-3 mm wide; receptacle elongate, 1-6 cm long (superficially resembling a Plantago inflorescence) | |
3 Petals absent (or modified into relatively inconspicuous nectaries or staminodia); sepals present and petaloid (white, yellow, yellow-green, cream, or blue). | |
8 Leaves all basal, or with a few alternate or whorled involucrate leaves on the stem; style not plumose. | |
11 Leaves palmately or pedately lobed or divided; sepals green, greenish, dull yellow, or whitish; petals modified into tubular nectaries; [introduced, rarely persistent or escaped from cultivation]. | |
12 Sepals 5, green or maroon, persistent in fruit; cauline leaves present; leaf margins sharply and finely serrate; [tribe Helleboreae] | |
13 Cauline leaves absent, except the 3 involucral bracts immediately subtending the flower; [tribe Cimicifugeae] | |
13 Cauline leaves present, alternate, the uppermost > 1 cm below the flower; [tribe Helleboreae] |
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3 Carpels 3-6; plants 1-5 dm tall; [introduced, rarely persistent or escaping]. | |
6 Leaves all basal, or with a few alternate or whorled involucrate leaves on the stem; style not plumose. | |
7 Basal leaves linear to linear-spatulate, mostly 4-8 cm long, 1-3 mm wide; receptacle elongate, 1-6 cm long (superficially resembling a Plantago inflorescence); [tribe Ranunculeae] | |
9 Cauline leaves opposite or whorled, or reduced to 3 sepal-like involucral bracts immediately subtending the flower; sepals absent (but in “Hepatica” mimicked by the bracts); [tribe Anemoneae] | |
9 Cauline leaves alternate; sepals present; [tribe Ranunculeae] | |
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1 Leaflets linear, < 1.5 mm wide. | |
3 Terrestrial; [exotic]. | |
4 Flower lacking involucre; pistils simple. | |
9 Sepals petaloid, conspicuous, white (or cream, rose, pink, or tinged with green). | |
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3 Leaflets linear; [exotics]. | |
4 Flowers in a raceme, not subtended by an involucre; fruit follicular, each with a 1-2 mm long beak; [subfamily Ranunculoideae, tribe Delphineae] | |
5 Follicles borne on stipes, forming an umbel-like cluster; rhizomes yellow or orange; [subfamily Coptidoideae] | |
5 Follicles sessile; rhizomes brown or tan; [subfamily Thalictroideae]. | |
1 Fruit an achene. | |
7 Leaves divided into numerous linear segments, all of which are < 1 mm wide. | |
8 Plant aquatic (if leaves divided into numerous linear segments); [subfamily Ranunculoideae, tribe Ranunculeae] | |
9 Achenes 3-5 mm long, glabrous, with a persistent beak 0.5-1 mm long; [subfamily Ranunculoideae, tribe Adonideae] | |
9 Achenes 1.6-2 mm long, tomentose, with a persistent beak 3.5-4.5 mm long; [subfamily Ranunculoideae, tribe Ranunculeae] | |
7 Leaf segments rounded or cleft, > 1 mm wide. | |
10 Leaves basal and/or cauline, cauline leaves (if present) alternate (leaflike involucral bracts sometimes present and opposite or whorled). | |
11 Leaflike involucral bracts not present. | |
13 Leaflets many, unlobed or typically with 3-9 rounded lobes; [subfamily Thalictroideae] |
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2 Leaves 3-foliolate, lacking tendrils; shrub, liana, or tree. | |
5 Leaflets 3-5 (-7), coarsely and jaggedly serrate, with < 5 teeth per leaflet side; fruit a schizocarp of 2 samaroid mericarps (maple “keys”) | |
6 Flowers either white, radially symmetrical, with separate petaloid sepals (Clematis), or blue, bilaterally symmetrical, with fused petals (Vitex). | |
7 Leaves 3-more-foliolate; flowers white, radially symmetrical, uniseriate, with white petaloid sepals and no petals | |
8 Leaves palmately compound. | |
12 Leaves pinnately compound, with 7-15 coarsely serrate leaflets; perianth biseriate, with a green synsepalous calyx and an orange sympetalous corolla; fruit an elongate capsule, with many winged seeds; stems to 20 cm in diameter, with tan bark | |
12 Leaves either pinnately compound, the leaflets 3-7 and coarsely serrate, or more complexly compound, the leaflets 5-many, not serrate though often lobed; perianth uniseriate, with a white, pink, or purplish aposepalous calyx and no corolla; fruit an aggregate of plumose achenes; stems to 1 cm in diameter, brown or green | |
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1 Inflorescence an involucrate head subtended by phyllaries, heads solitary or many, variously arrayed in secondary inflorescences; fruit a cypsela | |
1 Inflorescence various, but not as above; fruit various, not as above. | |
2 Leaves pinnately compound. | |
3 Leaves odd-pinnate. | |
5 Plants often with a mix of mostly opposite, deeply 3-lobed leaves or trifoliate leaves (leaves sometimes simple); flowers pink or purplish-white, axillary; plants annual | |
2 Leaves palmately compound. | |
7 Plants perennial; flowers radially symmetric, showy, variously colored; plants typically not strongly resinous or glandular; inflorescences terminal |
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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, e.g. Pycnanthemum in LAMIACEAE, but then with other features differing, such as stamens 4, or green calyx present, or fruit a schizocarp of mericarps, etc.). | |
5 Leaves herbaceous, suborbicular, about as long as wide or wider than long; calyx 3- or 4-merous; stamens 4, 8, or 12. | |
5 Leaves fleshy, linear, lanceolate, to broadly ovate, at least slightly longer than broad; calyx 5-merous; stamens 3, 5, or 10. | |
4 Perianth in 2 whorls (sepals and petals both present). | |
8 Petals connate into a tube (at least basally); inflorescence often a head or dense terminal cyme (also axillary, or solitary on long peduncles). | |
14 Leaves serrate; corolla bilaterally symmetrical (especially the flowers near the outer edge of the head); inflorescence a head | |
17 Inflorescence a cyathium, consisting of a single pistillate flower (reduced to a single 3-carpellate pistil) and 2 or more staminate flowers (each reduced to 1 stamen), borne in a cup-like involucre, the involucre bearing pointed or rounded glands, these sometimes brightly colored and petaloid, mimicking an individual flower (the cyathia then secondarily arranged in terminal cymes, or solitary and axillary, etc.); fresh plants with milky juice; fruit a 3-lobed, 3-locular capsule | |
17 Inflorescence not a cyathium (and staminate or bisexual flowers with > 1 stamen, except Callitriche in PLANTAGINACEAE); fresh plants lacking milky juice; fruit various, not as above. | |
18 Flowers 1 (or 2) in leaf axils; leaves entire. | |
19 Flowers bisexual; sepals 4; flowers with 2, 4, or 6 stamens. | |
16 Perianth in 2 whorls (sepals and petals both present). | |
27 Pistils 4-5, in a single whorl; stamens 4, 5, 8, or 10; fruit an aggregate of follicles | |
28 Petals not at all connate, not even at their bases. | |
31 Petals 4-7; sepals 4-7, normally monomorphic; stamens 4, 5, 6, 8, 10, or 12 (or sometimes rarely 2 or 3). | |
28 Petals connate at least for a short distance at their bases. | |
35 Pistils 2, united only by the style and stigma; fruit a schizocarp of 2 1-carpellate follicles (often single by abortion); plant with milky juice when fresh (except Catharanthus); leaves entire | |
35 Pistil 1 (of 2-5 fused carpels); fruit either a 2-5-carpellate capsule or of 2 or 4 1-seeded nutlets derived from 2 carpels; plant lacking milky juice; leaves entire or serrate. | |
38 Inflorescence a terminal cyme; corolla salverform, with an elongated and very narrow tube, pink or white; capsule 3-locular | |
38 Inflorescence various but not cymose, of terminal or axillary racemes or panicles, or of solitary axillary flowers; corolla connate only at the base, the petals appearing nearly separate (not salverform); capsule 1-locular | |
36 Ovary and capsule 2-carpellate; fruit either a 2-locular capsule or of 2 or 4 1-seeded nutlets derived from 2 carpels. | |
40 Capsule septicidal; corolla white, pink, blue, yellowish white, or greenish white; inflorescence either a terminal or axillary cyme, or a terminal panicle or raceme, or a terminal or axillary cyme reduced to 1 or a few flowers | |
40 Capsule loculicidal and also deeply 2-lobed; corolla white, pink, or scarlet with a yellow interior; inflorescence of cymosely arranged spikes | |
42 Fruit a schizocarp of 4 1-seeded nutlets; inflorescence terminal, of cymes; corolla ca. 5 mm long; leaves prominently 3-veined | |
42 Fruit a capsule; inflorescence axillary, of cymes or clusters (often reduced to a solitary flower); corolla > 12 mm long; leaves with single primary vein | |
41 Leaves serrate; corolla salverform, the tube narrow and nearly the same diameter for most of its length; inflorescence a terminal spike, raceme, raceme of racemes, or head. | |
34 Corolla bilaterally symmetrical (or the corolla 2-lipped but the corolla lobes twisted so as to make the flower asymmetrical); fertile stamens fewer than the corolla lobes (except Plantago in PLANTAGINACEAE, which is equal, with 4 each; a few genera have a 5th, sterile, stamen which is obviously different in form than the 4 fertile stamens) (note that many corollas are bilabiate and the number of corolla lobes, 4 or 5, may be difficult to interpret); carpels 2. | |
44 Carpels 2, each carpel slightly to deeply lobed, separating at maturity into 4 half-carpellate units (not separating in Phyla in VERBENACEAE); fruit a schizocarp of 4 mericarps (or 2 nutlets in Phyla in VERBENACEAE). | |
45 Inflorescence a thyrse, verticillaster, or terminal cyme, the flowers borne in cymose lateral branches; corolla strongly bilaterally symmetrical (rarely nearly radially symmetrical); stems square in ×-section (or sometimes rounded, especially on older growth); fresh plants often (but not always) aromatic | |
45 Inflorescence of spikes, racemes, or heads, the flowers or fruits single at nodes; corolla often nearly radially symmetrical; stems rounded in X-section (rarely square); fresh plants usually not aromatic | |
47 Corolla 4-5-lobed, either strongly bilabiate or salverform (Pseuderanthemum in ACANTHACEAE); white, blue, or yellow. | |
53 Flowers in terminal racemes, panicles, or spikes, the inflorescence not interspersed with large, leaf-like bracts. | |
54 Sepals connate for at least 0.3× their length to form a tube (this cup-like and flaring in Scrophularia in SCROPHULARIACEAE). | |
55 Inflorescence a diffuse panicle; corolla 5-11 mm long, reddish-brown (sometimes with some yellow); fruit a septicidal capsule | |
55 Inflorescence of 1 or more terminal (and sometimes upper axillary) spikes or racemes; corolla 10-50 mm long (6-8 mm long in Phryma in PHRYMACEAE), white, pink, blue, purple, or yellow; fruit either a loculicidal capsule (OROBANCHACEAE) or a single seeded achene (Phryma in PHRYMACEAE). | |
56 Corolla 6-8 mm long, white to pale pink; fruit a 1-seeded achene contained in the accrescent calyx, this “lopping down” against the inflorescence axis | |
57 Sepals separate to the base or nearly so, not forming a tube. | |
59 Leaves entire, either mostly larger or smaller [see below]; plant not blackening on drying | |
60 Leaves 3-30 cm long, narrowly elliptic to lanceolate, > 2× as long as wide; plants erect or the stems sprawling; [plants mostly of uplands] | |
57 Sepals connate for at least 0.3× their length to form a tube. | |
61 Corolla yellow, orange, or red. | |
63 Corolla red or orange, with a very narrow, cylindrical tube, the lobes then flaring into a limb about 1 cm across; plants blackening on drying; [rare exotic, in crop fields, a noxious hemiparasitic weed under quarantine] | |
63 Corolla yellow, not narrowly cylindrical, the lower lip arched; plants not blackening on drying; [rare, in seepage wetlands] | |
61 Corolla white, pale blue, lavender, or pink (sometimes with some yellow). | |
64 Corolla white, blue, or combinations of blue and white (sometimes with some yellow markings); leaves broader, mostly lanceolate; plants not blackening on drying; corolla strongly bilabiate. | |
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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 tightly grouped, but then with other features differing, such as stamens 4, or green calyx present, or fruit a schizocarp of mericarps, etc.). | |
2 Flowers larger, individually conspicuous; perianth present, the petals or sepals brightly colored; fruit a capsule (or aggregate of achenes in Clematis in RANUNCULACEAE or schizocarp of 4 mericarps in Glandularia in VERBENACEAE). | |
3 Flowers radially symmetrical; stamens 5 or many; fruit a capsule or aggregate of achenes. | |
3 Flowers bilaterally symmetrical (sometimes only slightly so); stamens 4 (or 2 in Veronica in PLANTAGINACEAE); fruit a capsule or schizocarp of mericarps. | |