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Key to Solanum

Solanaceae

Solanum

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1 Stems, and often leaves, armed with sharp prickles or spines.
  2 Shrubs to 3.5 m tall; leaves sessile; leaves paired and of different sizes
  2 Herbs to 2 (-3) m tall or shrubs, small trees, or scrambling, vine-like shrubs to 5 m tall or long; leaves petiolate; leaves not paired.
    3 Shrubs, small trees, or scrambling, vine-like shrubs to 5 m tall or long; stems with either recurved or straight prickles.
      4 Berry yellow, 1.0-1.5 cm in diameter; corolla shallowly lobed, the sinuses < ½ of the way to the base
      4 Berry red, < 1 cm in diameter; corolla lobed nearly to the base, rotate
        5 Prickles straight
        5 Prickles recurved
    3 Herbs to 2 (-3) m tall; stems with prickles, but these not strongly recurved.
          6 Berry 2.5-5 cm long, densely hirsute with hairs (2-) 3-5 mm long
          6 Berry 0.5-5 cm long, glabrous or pubescent with hairs < 1 mm long.
             7 Berry enveloped at least until near maturity by prickly calyx; leaves regularly and strongly pinnately parted or very deeply divided (sinus depth greater than 1/2 distance from leaf margin to midvein).
               8 Corolla yellow; inflorescence stellate-pubescent only; calyx tightly enveloping the fruit; seeds coarsely undulate-rugose
               8 Corolla violet to (rarely) white, anthers all similar; inflorescence glandular-villous and stellate-pubescent; calyx loosely or tightly enveloping the fruit; seeds minutely reticulate-pitted.
                 9 Anthers unequal, the lowest violet-tinged, longer, and incurved; fruiting pedicels erect; berry enclosed by the closely fitting and often adhering calyx
                 9 Anthers about equal, all yellow; fruiting pedicels spreading; berry loosely enclosed by the calyx
             7 Berry not enveloped by prickly calyx; the leaves not pinnately parted or divided (except in S. sisymbriifolium), or only weakly so (sinus depth < ½ the distance from leaf margin to midvein).
                   10 Berry (1.5-) 2-5 cm long; lower leaf surface pubescent with simple hairs, these viscid (gland-tipped) or not.
                     11 Ripe berry orange-red to reddish, leaves deeply lobed (sinus depth up to 1/2 distance from leaf margin to midvein); plants with eglandular, villous pubescence; seeds winged
                     11 Ripe berry yellow, immature berry green with white mottles, leaves shallowly lobed (sinus depth typically < 1/3 distance from leaf margin to midvein); plants glandular-viscid; seeds not winged
                   10 Berry < 2 cm in diameter; lower leaf-surface stellate-pubescent.
                       12 Leaves linear-lanceolate, 1-3 cm wide, trichome clusters 0.5 mm broad, with 12 or more rays
                       12 Leaves ovate to elliptic, 2-8 cm wide, often lobed or cleft, trichome clusters 1 mm broad, with 5-10 rays.
                          13 Leaves pinnately parted or divided, the segments often pinnately lobed; calyx enveloping fruit when ripe, berry red; plant annual
                          13 Leaves irregularly lobed or cleft, the lobes or segments entire; calyx not enveloping fruit when ripe; berry yellowish orange, never red; plant perennial.
                            14 Stellate trichomes of lower leaf surface stipitate, the 6-8 rays, the central one as long as or shorter than the lateral rays, of 1 cell; corolla 3-4 cm wide, calyx 8-12 mm long
                            14 Stellate trichomes of lower leaf surface sessile, with 2-5 rays, the central one elongate, of 1-5 cells, and longer than the lateral rays; corolla 2-3 cm wide, calyx 5-7 mm long.
                              15 Leaves entire, margins at most sinuate; plants up to 2 dm in stature; prickles few, absent, and/or confined to midveins; corollas white; inflorescence with up to ca. 4 flowers; [rare plants of c. AL and wc. GA]
                              15 Leaves not entire, lobed, cleft, pinnately parted, or divided; plants 3-10 dm in stature; prickles more abundant and generally distributed; corollas purple, rarely white; inflorescence with up to ca. 15 flowers; [plants more widely distributed, weedy or ruderal].
                                16 Stems sparsely to moderately armed with prickles up to 12 mm long; inflorescences 2- to several-branched; corollas 2.0-4.4 cm in diameter; [mainly AL, FL, and GA, rarely MS]
                                16 Stems unarmed or sparsely armed with prickles up to 6 mm long; inflorescences unbranched or once branched; corollas 2.2-3.0 cm in diameter; [collectively widespread].
                                  17 Leaf margins deeply lobed to parted; sinuses of lobes reaching more than half the distance to the midvein or almost to the midvein; apex of leaf lobes typically rounded; [s. GA and FL]
                                  17 Leaf margins subentire, sinuate, or lobed; sinuses of lobes, when present, reaching less than half the distance to the midvein; apex of leaf lobes subacute to acute, sometimes rounded; [widespread]
1 Stems and leaves unarmed, lacking prickles or spines.
                                    18 Leaves compound (at least well-developed leaves), pinnatifid, or basally auriculate-lobed.
                                       19 Woody or suffrutescent climbing or twining vine; leaves regularly pinnatifid (to bipinnatifid) or basally auriculate-lobed.
                                         20 Leaves with 2 basal lobes or leaflets much smaller than the terminal one (some upper leaves simple); [mainly northwards]
                                         20 Leaves pinnately to bipinnately deeply lobed, usually with 3-9 lobes of relatively equal size; [peninsular FL]
                                       19 Herb, not twining; leaves pinnately compound or pinnatifid.
                                           21 Leaves sessile or short-petiolate, 1-5 cm long, regularly pinnatifid, the lobes similar in size and shape; plant more or less prostrate
                                           21 Leaves distinctly petiolate, 10-40 cm long, pinnately or bipinnately compound, the lateral leaflets ovate, often with smaller leaflets intercalated between the main leaflets; plant erect, scrambling, or sprawling.
                                             22 Stem pubescence glandular; anthers opening by longitudinal slits; seeds hairy; [tomato]
                                    18 Leaves not compound or auriculate-lobed.
                                               23 Shrubs and small trees; [mainly FL and s. TX southwards, rarely northwards].
                                                 24 Berry stellate-pubescent; [FL and s. TX southwards].
                                                    25 Leaves of new growth with stipule-like auricled miniature leaves at the petiole base; corolla lavender to deep purple; [collectively widespread]
                                                    25 Leaves lacking associated stipule-like small leaves; corolla white.
                                                      26 Leaf blade broadest below the midpoint, short-cuneate or nearly truncate at the base; calyx and corolla densely short-stellate pubescent
                                                      26 Leaf blade broadest above the midpoint, narrowly cuneate at the base; calyx and corolla shaggy-pubescent with stellate hairs
                                                 24 Berry glabrous; [mainly FL and s. TX southwards, rarely northwards].
                                                        27 Plants glabrous or if sparsely pubescent, the hairs simple.
                                                          28 Leaves glaucous; Inflorescence a branched raceme
                                                          28 Leaves green; inflorescence a congested cyme borne opposite a leaf
                                                        27 Plants stellate-pubescent.
                                                            29 Flowers 1-3 in an axillary fascicle.
                                                              30 Leaf blades tapered to base; leaf blades widest at or above the midpoint; [exotic]
                                                              30 Leaf blades cordate or truncate at base; leaf blades widest near the base; [native, TX]
                                                            29 Flowers either in a simple to compound cyme, or in a racemiform cyme.
                                                                 31 Inflorescence a racemiform cyme
                                                                 31 Inflorescence a simple or compound cyme
                                               23 Herbs; [collectively widespread].
                                                                   32 Corolla 10-16 mm long, lavender; fruits 10-15 mm in diameter, yellow when ripe (blackening with age); trichomes of stems and leaves stellate, with 9-13 branches
                                                                   32 Corolla 5-8 mm long, white to cream; fruits 5-10 mm in diameter, black, purple, green, orange, red, or dark yellow when ripe; trichomes of stems and leaves simple (when present).
                                                                     33 Foliage with glandular trichomes; fresh plants sticky to the touch.
                                                                       34 Mature berry orange, red or dark yellow, usually somewhat ellipsoid; calyx lobes with translucent sinuses
                                                                       34 Mature berry green, purple or black, usually globose or subglobose; calyx lobes without translucent sinuses.
                                                                         35 Calyx lobes not enlarged and enclosing the berry
                                                                         35 Calyx lobes enlarged in fruit and enclosing the berry.
                                                                           36 Leaf bases attenuate to cuneate; inflorescences mostly internodal, with 4-8 (-10) flowers; corolla with a central greenish yellow star with black or purple margins; berries dark green to greenish brown, marbled with white, becoming translucent and shiny; stone cells 1-3, ca. 0.5 mm in diameter
                                                                           36 Leaf bases cordate or truncate; inflorescences mostly leaf-opposed, with 2-5 (-7) flowers; corolla with a central greenish yellow star without black or purple margins; berries pale green, not marbled with white, becoming matte, opaque; stone cells 4-6, 0.8-1 mm in diameter
                                                                     33 Foliage lacking glandular trichomes, sometimes with a few scattered trichomes with glandular tips, but not markedly glandular (fresh plants not sticky to the touch).
                                                                              37 Leaves deeply pinnatifid; prostrate herbs with fleshy leaves
                                                                              37 Leaves with entire or various toothed margins, not pinnatifid; plants erect or scrambling (rarely prostrate, if so, the leaves NOT fleshy).
                                                                                38 Mature berries orange, red or dark yellow (shiny and translucent at maturity); calyx lobes with translucent sinuses
                                                                                38 Mature berries green, purple or black; calyx lobes without translucent sinuses.
                                                                                  39 Anthers 0.7-1.5 mm long.
                                                                                    40 Mature berries dropping without the pedicel; calyx lobes strongly reflexed in fruit; stone cells (sclerotic granules) (0-) 2-4 (-6) per berry
                                                                                    40 Mature berries dropping with the pedicel; calyx lobes appressed to spreading in fruit; stone cells (6-) 8 (-9) per berry
                                                                                  39 Anthers > 2 mm long.
                                                                                      41 Buds narrowly ellipsoid to narrowly ovoid; corolla deeply stellate with narrowly lanceolate strap-like lobes; berries shiny, with > 10 stone cells; prostrate herbs
                                                                                      41 Buds ellipsoid to ovoid to obovoid; corolla stellate with triangular to deltate lobes, not markedly lanceolate and strap-like; berries matte or somewhat shiny, usually with < 10 stone cells; erect or straggling herbs
                                                                                        42 Stone cells present in mature berries, always more than 2; corolla (10-) 15-20 mm in diameter
                                                                                           43 Anthers (2.7-) 3-4.5 mm long, slightly tapering to the tip; buds ovoid, tapering to the apex; free portion of the filaments minute, ca. 1/4 the length of the anther; corolla to 20 mm in diameter
 Solanum douglasii
                                                                                           43 Anthers less than 3 mm long, ellipsoid with straight sides; buds ellipsoid; free portion of the filaments half the length of the anthers; corolla < 15 mm in diameter.
                                                                                             44 Basal flower in the inflorescence with the articulation above the rachis; calyx lobes unequal, lanceolate, the longest one 1.7-4.5 mm long; seeds 1.8-2 mm long; stone cells 2-4; [prairies and open woodlands, mw. US]
                                                                                             44 All flowers with the articulation at the inflorescence rachis; calyx lobes equal, deltate, 0.5-1 mm long; seeds 1.2-1.5 mm long; stone cells usually > 5; [forests and coastal areas, se. US]
                                                                                        42 Stone cells in mature berries absent (occasionally 2); corolla < 15 mm in diameter.
                                                                                               45 Berries 10-20 mm in diameter, shiny, slightly flattened; fruiting pedicels strongly spreading; anthers somewhat tapering, often drying brownish orange; [cultivated, perhaps a waif]
                                                                                               45 Berries < 15 mm in diameter, somewhat shiny, matte or slightly glaucous, globose; fruiting pedicels weakly spreading or more usually deflexed; anthers ellipsoid, not drying brownish orange; [native, adventive, or naturalized].
                                                                                                 46 Inflorescences with the flowers spaced along the rachis; anthers 1.8-2.5 mm long; fruiting pedicels spreading; berry surface slightly shiny; seeds 1.8-2 mm long
                                                                                                 46 Inflorescences with the flowers clustered at the tips (sub-umbelliform), only a few spaced along the rachis; anthers > 2 mm long; fruiting pedicels deflexed, usually strongly so; berry surface matte or glaucous; seeds 1-1.5 mm long.
                                                                                                   47 Peduncle in fruit at right angles or more usually strongly deflexed downwards; berries 4-9 mm in diameter; calyx lobes appressed to surface of berry in fruit; styles exserted to 1.5 mm from the anther cone at anthesis; [adventive in our area]
                                                                                                   47 Peduncle in fruit slightly ascending, not deflexed downward; berries 8-14 mm in diameter; calyx lobes reflexed in fruit; style exserted 2-2.5 mm from the anther cone at anthesis; [coastal habitats, native in our area]