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| 1 Shrubs to 2 m tall, erect; stems hollow |
| 1 Herbaceous vines (trailing or twining) or herbs (erect); stems solid or hollow. |
| ..2 Corollas campanulate, the tube < 2× as long as its diameter; fruit indehiscent; [Old World Clade]. |
| ....3 Young stems glabrous; leaf undersurfaces glabrous; corollas lavender (purple, rose, or white), darker in the tube, 6-7 cm long |
| ....3 Young stems densely white-hairy; leaf undersurfaces white-hairy; corollas cream-white, with pale yellow pleats and with maroon markings in the tube, 2.5-3 cm long |
| ..2 Corollas salverform or funnelform, the tube > 4× as long as its diameter; fruit a dehiscent capsule. |
| ......4 Corollas salverform, the long narrow tube cylindrical (with sides more-or-less parallel) for most of its length, the limb abruptly flaring at the summit of the tube. |
| ........5 Corollas 3-15 cm long, predominantly lavender to white; flowers open from evening until early morning. |
| ..........6 Leaves tomentose beneath; corolla mostly white on the outer surface, lavender to purple on the inner surface, thus bicolored in-and-out; [of outer Coastal Plain dunes, hammocks, and shell middens from se. NC southward] |
| ..........6 Leaves glabrous (or with scattered hairs or large fleshy hairlike structures) beneath; corolla either white on both surfaces or lavender on both surfaces, not bicolored in-and-out; [weedy, widespread, of disturbed habitats]. |
| ............ 7 Sepals obtuse, 10-25 mm long. |
| ............ ..8 Corollas lavender, the throat darker; stems bearing dark, fleshy, hairlike structures; [non-native, rare introduction] |
| ............ ..8 Corollas white, with 5 yellowish lines; stems glabrous; [native, s. and c. peninsular FL] |
| ............ 7 Sepals acute to caudate, 6-14 mm long. |
| ............ ....9 Corollas 10-14 cm long, white with 5 greenish or yellowish lines; fruits 2-3 cm long, borne on dry pedicels |
| ............ ....9 Corollas 3-7.5 cm long, whitish to violet or lavender; fruits 1.8-2 cm long, the pedicels fleshy |
| ........5 Corollas 1.4-5 cm long, red, orange, or yellow; flowers open from early morning to late morning or late afternoon. |
| ............ ......10 Corolla tubes 3-4 mm in diameter; plants perennial from tubers; [s. FL] |
| ............ ......10 Corolla tubes 1-3 mm in diameter; plants annual from fibrous roots; collectively widespread in our region]; [Quamoclit Clade]. |
| ............ ........11 Leaf blades pinnately divided into 11-31 (or more) linear or lanceolate segments (with parallel sides or narrowing towards the base) |
| ............ ..........12 Leaf blade segments 11-19, lanceolate, 3-7 mm wide, parallel-sided near the base or narrowing towards the base, the apical portion of the segment narrowly triangular |
| ............ ..........12 Leaf blade segments 11-31 (or more), linear, < 2 mm wide, parallel-sided |
| ............ ........11 Leaf blades entire, or angled, or shallowly to deeply palmately 3-7-lobed (and then the lobes broadening towards their bases). |
| ............ ............ 13 Leaf blades deeply 3-7-lobed |
| ............ ............ 13 Leaf blades unlobed (not counting the cordate base), or with leaves shallowly 3-lobed. |
............ ............ ..14 Inner sepals 4-6 mm long; pedicels becoming reflexed in fruit; leaves usually unlobed (though sometimes with a few coarse dentate teeth) |
| ............ ............ ..14 Inner sepals 2-3 (-4) mm long; pedicels remining erect in fruit; leaves usually 3-lobed about halfway from margin to base |
| ......4 Corollas funnelform, the short to long tube expanding in diameter upwards from below the middle, the limb gradually to abruptly flaring at the summit of the tube. |
| ............ ............ ....15 Pedicels and peduncles with spreading, ascending, or reflexed trichomes; gynoecium 3-parted; sepals 8-25 (-30) mm long; corollas deep purple to rich blue or light blue (rarely white or bright pink), the tube and throat lighter in color (white or yellow); [Pharbitis clade]. |
| ............ ............ ......16 Sepals soft-pilose on the outer surface with slender trichomes |
| ............ ............ ......16 Sepals hispid-pilose on the outer surface, with swollen-based trichomes. |
| ............ ............ ........17 Corolla pink to purple (rarely white or blue); sepals oblong-lanceolate, merely obtuse or acute and without a prominently narrowed (caudate) tip; leaves entire or 3–5-lobed |
| ............ ............ ........17 Corolla blue with a white tube (drying pink); sepals ovate with an elongate or caudate apex longer than the sepal body, notably accrescent in fruit; leaves usually 3-lobed. |
| ............ ............ ..........18 Sepals < 2 cm long at anthesis, abruptly narrowed upwards, the long subacute tips strongly spreading or recurved outwards; corolla < 3.5 cm long; peduncles very short. |
| ............ ............ ..........18 Sepals ca. 3 cm long at anthesis, gradually narrowed upwards, the long acute tips suberect, straight, scarcely spreading; corolla 4–4.5 cm long; peduncles long or short |
| ............ ............ ....15 Pedicels and peduncles glabrous or with short, appressed trichomes; gynoecium 2-parted; sepals 4-15 mm long; corollas mainly pink, lavender, or white, the tube and throat mainly deeper pink, purple, or maroon (but some species – I. tricolor, I. aristolochiifolia -- blue with white or yellow throats). |
| ............ ............ ............ 19 Leaves palmately, pinnately, or pedately compound or pseudocompound (so deeply parted as to appear superficially compound). |
| ............ ............ ............ ..20 Leaves pedately compound, the leaflets or segments 1.5-3 mm wide; corollas 1-1.2 cm long, white; [TX] |
| ............ ............ ............ ..20 Leaves palmately or pedately compound, the leaflets or segments 3-10 mm wide; corollas 1.8-6 cm long, lavender, pink, or purplish. |
| ............ ............ ............ ....21 Corollas 4-6 cm long; pedicels 1-2.5 cm long, straight; leaves pinnately dissected (the pair of lobes about the basal pair diverging from the midvein several mm above the basal pair); axillary buds developing stipule-like leaves |
| ............ ............ ............ ....21 Corollas 1.8-3 cm long; pedicels 5-10 cm long, spiralled; leaves palmately dissected; axillary buds not developing leaves |
| ............ ............ ............ 19 Leaves simple, either unlobed or with 2-7 shallow lobes. |
| ............ ............ ............ ......22 Leaves linear, 2-8 mm wide, > 10× as long as wide; stems erect to ascending, bushy-branched, neither trailing nor twining |
| ............ ............ ............ ......22 Leaves broader, > 20 mm wide, < 5× as long as wide; stems either trailing or twining. |
| ............ ............ ............ ........23 Stems trailing, rooting at the nodes; leaf apex emarginate, truncate, obtuse, or acute. |
| ............ ............ ............ ..........24 Corollas lavender; larger leaves not lobed (though notched at the apex on at least the larger, better-developed leaves of I. brasiliensis) |
| ............ ............ ............ ............ 25 Leaves rounded, acute, or short-acuminate at the apex; sepals unequal, the outer 5-6 mm long, , thicker and about 1/2 as long as the herbaceous inner sepals |
| ............ ............ ............ ............ 25 Leaves emarginate at the apex; sepals essentially equal, 5-11 mm long |
| ............ ............ ............ ..........24 Corollas white with a white or purple throat (I. aquatica) or yellow or purple throat (I. imperati); larger leaves either hastate (I. aquatica) or 3-7-lobed (I. imperati). |
| ............ ............ ............ ............ ..26 Leaves hastate, the apex acute to acuminate; [plant aquatic] |
| ............ ............ ............ ............ ..26 Leaves (the larger) 3-7-lobed, the lobe apices rounded, truncate, or emarginate; [plant of dunes and beaches] |
| ............ ............ ............ ........23 Stems erect or twining, not rooting at the nodes (except sometimes in I. batatas); leaf apex acute to acuminate. |
| ............ ............ ............ ............ ....27 Corollas blue, the throat white or yellow; sepals 3-7 mm long. |
| ............ ............ ............ ............ ......28 Corollas 1.5-2.5 cm long; calyx 3-5 mm long, muricate; inflorescence axis clasped by the cordate leaf base |
| ............ ............ ............ ............ ......28 Corollas 3.5-6 cm long; calyx (4-) 6-7 mm long, glabrous; inflorescence axis free |
| ............ ............ ............ ............ ....27 Corollas pink, pink-purple, or white, the throat pink or purple; sepals 4-15 mm long. |
| ............ ............ ............ ............ ........29 Leaf bases sagittate or hastate. |
| ............ ............ ............ ............ ..........30 Leaves glabrous; sepals oval, 8-9 mm long, apex obtuse to rounded, mucronulate, coriaceous, glabrous; corollas 5-6 cm long; [widespread in the outer Coastal Plain from ne. NC south to s. FL, westo s. TX, and scattered elsewhere as an introduction] |
| ............ ............ ............ ............ ..........30 Leaves pubescent; sepals 5-8 mm long, ovate-lanceolate to oblong-lanceolate or lanceolate, apex acuminate, mucronate, ciliate; corollas 3-4 cm long; [s. FL] |
| ............ ............ ............ ............ ........29 Leaf bases cordate (or rarely cuneate or truncate in some species). |
| ............ ............ ............ ............ ............ 31 Sepals (especially the outer) with strongly raised-ribbed venation; seeds pilose with brownish hairs ca. 5 mm long. |
| ............ ............ ............ ............ ............ ..32 Leaf blades cordate at base, ovate (and often pandurate) in shape, 1-2.5× as long as wide; [widespread in our region] |
| ............ ............ ............ ............ ............ ..32 Leaf blades broadly cuneate, truncate or shallowly cordate at base, 2-3.5× as long as wide; [KS, OK, and TX] |
| ............ ............ ............ ............ ............ 31 Sepals with venation inconspicuous and planar or only the midvein obvious; seeds glabrous, puberulent, or lanose. |
| ............ ............ ............ ............ ............ ....33 Corollas 5-9 cm long, ca. 6 cm in diameter (across the limb); seeds ca. 8 mm long; [s. TX] |
| ............ ............ ............ ............ ............ ....33 Corollas 1-4.5 cm long, 1-4.5 cm in diameter (across the limb); seeds 2.8-7 mm long; [collectively widespread in our region]. |
| ............ ............ ............ ............ ............ ......34 Sepals 4-6 mm long; seeds with surface minutely tomentulose, densely pilose on the angles; capsules conical, 7-12 mm long |
| ............ ............ ............ ............ ............ ......34 Sepals 6-15 mm long; seeds with surface glabrous, the angles sometimes short pubescent; capsules subglobose, 4-8 mm long; [Batatas Clade]. |
| ............ ............ ............ ............ ............ ........35 Corollas 2-4.5 cm long, 2.2-3.2 cm in diameter across the limb, at least partly pink to lavender (or entirely white in I. batatas); seeds shortly pubescent on the angles. |
| ............ ............ ............ ............ ............ ..........36 Sepals unequal in length, oblong-ovate, with acute to caudate apices; leaves mostly 10-15 cm wide; [cultivated, rarely persistent] |
| ............ ............ ............ ............ ............ ..........36 Sepals more-or-less equal in length, oblong-lanceolate, with acuminate apices; leaves 2-5 cm wide; [native, widespread in the southern portion of our region, especially in the Coastal Plain]. |
| ............ ............ ............ ............ ............ ............ 37 Sepals hispid-pilose or at least ciliate; leaf blades and stems hispid-pilose to sparsely pilose, rarely glabrous |
| ............ ............ ............ ............ ............ ............ 37 Sepals glabrous; leaf blades and stems glabrous |
| ............ ............ ............ ............ ............ ........35 Corollas 0.6-2.5 (-3.0) cm long, 1-2 cm in diameter across the limb, white or lavender; seeds glabrous. |
| ............ ............ ............ ............ ............ ............ ..38 Corollas white; seeds 5-6 mm long |
| ............ ............ ............ ............ ............ ............ ..38 Corollas pink or lavender; seeds 2.8-3.6 mm long. |
| ............ ............ ............ ............ ............ ............ ....39 Sepals 5-7 mm long, oblong |
| ............ ............ ............ ............ ............ ............ ....39 Sepals 8-14 mm long, lanceolate. |
| ............ ............ ............ ............ ............ ............ ......40 Sepals mostly 8-11 mm long, subequal; corolla 2-2.5 cm in diameter across the limb |
| ............ ............ ............ ............ ............ ............ ......40 Sepals mostly 10-14 mm long, equal; corolla 1.5-2 cm in diameter across the limb |