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Support the Flora of the Southeastern US

2024 has been a banner year for making the best flora we can imagine. We've created:
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Keyed in multiple places:

Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.

Key to Rubiaceae

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1 Trees, shrubs, or woody vines.
  2 Prostrate or climbing woody vines (lianas), or sprawling shrubs.
    3 Leaf bases cordate, rounded, or truncate; leaves usually cordate, ovate, or deltoid shaped (occasionally hastate or broadly elliptic); corolla pale lilac colored; [non-native, se. US including FL; tribe Paederieae]
    3 Leaf bases cuneate to rounded but not cordate; leaves oblanceolate, lanceolate or linear; corolla white or yellow; [native, FL].
      4 Flowers and fruit sessile or subsessile; fruit yellow
      4 Flowers and fruit borne on pedicels or peduncles; fruit white
  2 Shrub or tree, plants upright.
        5 Inflorescence spherical or globular, in a tight round head; [collectively widespread]
          6 Fruits dry, dehiscent; [subfamily Cinchonoideae; tribe Naucleeae]
          6 Fruits fleshy, indehiscent; [subfamily Rubioideae; tribe Morindeae]
        5 Inflorescence cymose, thyrsoid, or corymbose (the inflorescence more open, not round and compact); [Coastal Plain, from s. SC southward].
             7 Plants with paired spines.
               8 Corolla lobes 4; leaves to ca. 1 cm long; fruit ca. 5 mm long
               8 Corolla lobes 5; leaves ca. 2-5 cm long ; fruit ca. 10 mm long
             7 Plants unarmed, not bearing spines or thorns.
                 9 Flowers orange-red; leaves usually whorled; [subfamily Cinchonoideae; tribe Hamelieae]
                 9 Flowers white, green, or maroon; leaves opposite.
image of plant
Show caption*© Scott Ward
                   10 Leaves linear, revolute, and strongly congested; [FL keys southward]
                   10 Leaves broad, not linear, nor strongly congested; [collectively more widespread]
                     11 Flowers solitary, terminal; [subfamily Ixoroideae; tribe Gardenieae]
image of plant
Show caption*© Alan M. Cressler
image of plant
Show caption*© Alan M. Cressler
                     11 Flowers in cymose or thyrsoid inflorescences.
image of plant
Show caption*© Scott Ward
image of plant
Show caption*© Alan M. Cressler
                       12 Inflorescence cymose; some calyx lobes expanded into pink or reddish “flags”; leaves deciduous; domatia not present; [of s. SC southward]; [subfamily Ixoroideae; tribe Condamineeae]
image of plant
Show caption*© Alan M. Cressler
                       12 Inflorescences thyrsoid; calyx lobes inconspicuous; leaves evergreen; domatia present in secondary vein axils; [of ne. FL southward]
image of plant
Show caption*© Sequoia Janirella Wrens, some rights reserved (CC BY-NC), uploaded by Sequoia Janirella Wrens
image of plant
Show caption*© Keith Bradley
                          13 Lateral veins 3-6 on either side of the midvein; fruit white; petals yellowish, > 6 mm long; [subfamily Cinchonoideae; tribe Chiococceae]
image of plant
Show caption*© Alan M. Cressler
                          13 Lateral veins 8-14 on either side of the midvein; fruit red; petals white, <5 mm long; [subfamily Rubioideae; tribe Psychotrieae]
1 Herbs (or creeping subshrubs in Mitchella).
                            14 Leaves whorled; [subfamily Rubioideae; tribe Rubieae]
                              15 Flowers paired, the ovaries connate and developing into a single fleshy red fruit; leaves roundish; creeping subshrub; [subfamily Rubioideae; tribe Mitchelleae]
                              15 Flowers single or in inflorescences with multiple flowers, the fruits either dry or fleshy and yellowish or black; leaves various; herb; [subfamily Rubioideae; tribe Spermacoceae].
                                       19 Flowers in axillary or terminal clusters, or single in axils, not involucrate; flowers 4-lobed; styles 2.
                                         20 Flowers usually solitary in leaf axils; fruit separating into 2 parts.
                                         20 Flowers in terminal and axillary clusters; fruits not separating into 2 parts.

Key J4: shrubs and subshrubs with opposite simple leaves with entire margins

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1 Aerial and epiphytic, hemiparasitic shrub
1 Terrestrial, autotrophic or hemiparasitic shrub or subshrub.
  2 Leaves succulent, nearly as thick as wide; [brackish to saline situations]
  2 Leaves herbaceous (succulent in Borrichia), much wider than thick; [various habitats].
    3 Creeping or short subshrubs, the stems primarily prostrate, < 2 dm tall.
      4 Well-developed leaves 4-6 per stem; inflorescence a head subtended by 4 large white bracts
      4 Well-developed leaves many per stem; inflorescence of individual flowers axillary in pairs or clusters or in terminal cymes.
        5 Flowers yellow; leaves with pellucid or dark punctate glands (use at least 10× magnification)
        5 Flowers white, pale pink, or deep pink; leaves lacking sessile, punctate glands.
          6 Leaves linear; flowers pale to deep pink, 5-merous
          6 Leaves orbicular or elliptic; flowers white to pale pink, 4-merous or 5-merous
    3 Upright or scrambling shrubs, > 3 dm tall
               8 Scrambling shrubs, armed with recurved paired spines at the nodes
                 9 Inflorescence a terminal head of many flowers.
                   10 Head flattened, either subtended by 4 large white bracts or by an involucre with >5 green phyllaries.
                     11 Head subtended by 4 large white bracts; leaves with prominently parallel-arcing secondary veins; flowers 4-merous
                     11 Head subtended by an involucre of >5 green phyllaries; leaves with venation otherwise; flowers 5-merous
                 9 Inflorescence otherwise, either of a solitary flower, or one of a wide variety of inflorescences with flowers attached at different points along branched or unbranched axes (e.g. axillary). {add: [Lagerstroemia] LYTHRACEAE; [Rosmarinus] LAMIACEAE; [Laguncularia] COMBRETACEAE; [Buxus] BUXACEAE; [Exochorda] ROSACEAE; various other [see spreadsheet]}
                       12 Inflorescence flat-topped (broader than long), terminal, a compound cyme or corymb.
                          13 Flowers bright yellow; stamens many; leaves < 1.5 cm wide; fruit a capsule; leaves with pellucid or dark punctate glands (use at least 10× magnification)
                          13 Flowers white or creamy; stamens 4-5; leaves > 1.5 cm wide; fruit a drupe; leaves lacking sessile, punctate glands.
                       12 Inflorescence either terminal and not flat-topped (longer than wide), or axillary and variously shaped, or terminal and solitary, or leaf-opposed.
                              15 Carpels many (> 9), either separate or fused; stamens many; perianth segments either many and undifferentiated into calyx and corolla, maroon, brown, or yellow (in CALYCANTHACEAE), or differentiated into a fleshy and persistent calyx of 5-9 sepals, and a deciduous corolla of 5-9 red (or white) petals (Punica in LYTHRACEAE).
                                16 Fruit a wrinkled, 3-7 cm long, brown to black, elliptical aggregate of nearly spherical, large achenes; flowers solitary in axils; perianth segments many and undifferentiated into calyx and corolla, maroon, brown, or yellowish; ovary superior; branches unarmed
                                16 Fruit a leathery, 4-15 cm in diameter, reddish, spherical berry with obpyramidal seeds surrounded by a juicy sarcotesta (pomegranate); perianth differentiated, the sepals fleshy and persistent on the fruit, the petals deciduous, 5-9, bright red to white; ovary inferior; branches typically armed with axillary spines
                              15 Carpels 1-5, fused; stamens either 1-5 or 8-10; perianth segments 4-5 or 8, variously colored; fruit a simple capsule, drupe, or berry (including berry-like fruit); flowers 2-many, in axillary or terminal inflorescences (pistillate flowers sometimes solitary in SANTALACEAE and THESIACEAE); [Eudicots].
                                  17 Ovary inferior; corolla absent, radially symmetrical, or bilaterally symmetrical; fruit either a berry or a 1-seeded drupe.
                                    18 Flowers unisexual and plants dioecious; corolla absent; pistillate flowers solitary, staminate flowers in pedunculate umbels or cymes, either terminal or axillary; fruit a 1-seeded drupe; leaves acute to acuminate at the apex
                                    18 Flowers bisexual and plants hermaphroditic; corolla present; flowers paired, terminal or axillary, or in axillary spikes; fruit a berry; leaves rounded, obtuse, to acute (or acuminate in Lonicera maackii) at the apex
                                  17 Ovary superior; corolla radially symmetrical (absent in Forestiera in OLEACEAE); fruit either a 1-4-seeded drupe, or a many-seeded berry (or berry-like fruit), or a capsule.
                                         20 Leaves with a conspicuous mix of silvery stellate hairs (upper) and rusty colored scales (lower); ovaries bearing rusty colored scales; flowers small, yellowish and inconspicuous; [nw. PA northward]
                                         20 Leaves glabrous or nearly so, lacking a conspicuous mix of stellate hairs adaxially and rusty scales abaxially; ovaries not bearing rusty colored scales; flowers of various size and color.
                                           21 Stamens 8-10, of 2 different lengths in each flower; petals separate, 4-5 (-7), pink purple, 10-15 mm long; stems strongly arching, rooting at the tips; [plants of flooded to saturated wetlands]
                                           21 Stamens either (1-) 2 (-4), or 4-5, or 10, all of the same length; petals fused (separate in RHAMNACEAE and BUXACEAE, but then < 5 mm long and white or cream), white, bright-yellow, lilac, or pink; stems erect (or at least not arching and rooting at the tips); [plants of various habitats].
                                               23 Fruit a loculicidal capsule, dehiscing into 3 valves; branches square in ×-section; leaves < 2 cm long; [exotic, cultivated and weakly established, of temperate areas]
                                               23 Fruit a drupe with 2-4 pyrenes; branches round or nearly so in ×-section; leaves > 2 cm long; [natives, of peninsular FL]
                                             22 Petals fused, 4-5, white, bright yellow, lilac, or pink; stamens either (1-) 2 (-4) or 10; fruit either a capsule or a 1-seeded drupe.