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Key to Rubiaceae

Rubiaceae

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1 Trees, shrubs, or woody vines.
(c) Ware, Richard & Teresa - CC-BY-NC, permission granted to NCBG
    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].
(c) Campos, Aidan
(c) Cressler, Alan M.
      4 Flowers and fruit sessile or subsessile; fruit yellow
(c) Bradley, Keith
      4 Flowers and fruit borne on pedicels or peduncles; fruit white
  2 Shrub or tree, plants upright.
(c) Keim, Mary - CC-BY-NC-SA, permission granted to NCBG
        5 Inflorescence spherical or globular, in a tight round head; [collectively widespread].
          6 Inside of corolla pubescent; [natives and non-native; widespread, including s. FL]
(c) Powell, Eric M - CC-BY-NC, permission granted to NCBG
             7 Fruits dry, dehiscent, composed of nutlets; lobes of the corolla smaller; [subfamily Cinchonoideae; tribe Naucleeae]
(c) Campos, Aidan
(c) Campos, Aidan
             7 Fruits fleshy, indehiscent, composed of drupe-like syncarps; lobes of the corolla larger (inflorescence with 1 petaloid calycophyll in M. citrifolia); [subfamily Rubioideae; tribe Morindeae]
(c) Bradley, Keith
        5 Inflorescence cymose, thyrsoid, or corymbose (the inflorescence more open, not globular); [Coastal Plain, from s. SC southward].
© Scott Ward
               8 Plants with paired spines.
(c) Bradley, Keith
                 9 Corolla lobes 4; leaves to ca. 1 cm long; fruit ca. 5 mm long
(c) Campos, Aidan
                 9 Corolla lobes 5; leaves ca. 2-5 cm long ; fruit ca. 10 mm long
(c) Bradley, Keith
                   10 Flowers orange-red; leaves usually whorled; [subfamily Cinchonoideae; tribe Hamelieae]
                   10 Flowers white, green, or maroon; leaves predominantly opposite.
© Scott Ward
                     11 Leaves linear, revolute, and strongly congested at branch tips; [FL keys southward]
                     11 Leaves broad, not linear, nor strongly congested (except sometimes in Guettarda); [widespread, including s. FL].
(c) Keith, Eric - CC-BY-NC, permission granted to NCBG
                       12 Flowers solitary, terminal, appearing Rose or Magnolia-like; [horticultural waif; subfamily Ixoroideae; tribe Gardenieae]
(c) Cressler, Alan M.
(c) Cressler, Alan M.
                       12 Flowers in cymose or thyrsoid inflorescences, not appearing Magnolia or Rose-like (sometimes singular in Exostema, but the corolla is conspicuously salverform); [natives, s. SC southward through FL]
(c) Sarabia, Francisco Farriols - CC-BY
                          13 Corolla salverform, the tube long and slender, ca. (1.5-) 2-9 cm long, the petals noticeably shorter than the tube (or if of similar length then the lobes linear, as in Exostema); [c. and s. FL only in our area].
(c) Bradley, Keith
                            14 Leaves ovate, elliptic, or lanceolate, not conspicuously rounded in shape (or at least this not predominant); corolla tube 2-5 cm long, the corolla lobes often recurved apically, linear and of similar length to corolla tube; stamens conspicuously exerted; [s. FL]
(c) Sarabia, Francisco Farriols - CC-BY
                            14 Leaves sub-orbicular to oval, conspicuously rounded in shape (the surfaces scabrous in G. scabra); corolla tube (1.5-) 2-9 cm long, the corolla lobes shorter than the corolla tube; [c. and s. FL]
(c) Bradley, Keith
                          13 Corolla not salverform (or if the tube somewhat lengthened not 2-5 cm long), the corolla lobes broadened and not typically recurved apically; stamens exerted or not; [s. SC southward through FL].
(c) Cressler, Alan M.
© Scott Ward
                              15 Inflorescence cymose; some calyx lobes expanded into pink or reddish “flags”, the corolla lobes often pink-dotted; leaves deciduous; domatia not present; [of s. SC southward]; [subfamily Ixoroideae; tribe Condamineeae]
(c) Cressler, Alan M.
                              15 Inflorescences thyrsoid; calyx lobes inconspicuous; leaves evergreen; domatia present or absent in secondary abaxial vein axils; [of ne. FL southward].
(c) Julie, Tuttle - C, permission granted to NCBG
                                16 Fruit large, fig-like (5-7 cm long berries), obovoid, green-colored when ripened and somewhat dull; [subfamily Ixoroideae; tribe Gardenieae]
                                16 Fruit smaller (pea-sized or smaller, ca. 4-6 mm in diameter), rounded and berry or drupe-like, white, red, or black colored when ripened, usually at least somewhat lustrous.
(c) Bradley, Keith
                                  17 Leaves with 8-14 pairs of prominently depressed secondary veins on the upper (adaxial) surface, the veins nearly arising perpindicular from the midvein and often curving (arcuate) toward the leaf margins (thus causing the leaf tissue to almost "rise" from between the veins), the blades herbaceous or membranous; fruit red; [subfamily Rubioideae; tribe Psychotrieae]
(c) Ward, Scott G - CC-BY
                                  17 Leaves usually with < 8 secondary veins, these not conspicuously depressed within the leaf blade (sometimes the midvein moderately depressed); the blades leathery; fruit black or white; [subfamily Cinchonoideae; tribe Chiococceae]
(c) Bradley, Keith
(c) Wrens, Sequoia Janirella - CC-BY-NC, permission granted to NCBG
                                    18 Inflorescence elongate-thyrsoid, pedicels bent to one side, petals yellowish; ripened fruit white; plants often vine-like or sprawling shrubs
(c) Cressler, Alan M.
                                    18 Inflorescence cymose or corymbose, usually terminal, petals whitish; ripened fruit black; plants upright shrubs
1 Herbs (or creeping subshrubs in Mitchella); [ADD Borreria]
(c) Fleming, Gary P.
                                       19 Leaves whorled; [subfamily Rubioideae; tribe Rubieae]
                                         20 Fruit variously colored but not bright blue to purple, the calyx not partially persistent or inconspicuously so; [widespread natives and non-natives].
(c) Stuart, Will
                                           21 Flowers paired, the ovaries connate and developing into a single fleshy red fruit; leaves roundish; creeping subshrub; [subfamily Rubioideae; tribe Mitchelleae]
                                           21 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].
                                                 24 Flowers variously colored, often pinkish-purple or whitish-pink; leaf blades often > 5 cm long; plants perennial, erect, not succulent; [waif, c. and s. FL]
                                                 24 Flowers white; leaf blades < 5 cm long; plants annual, creeping or only partially erect, partially succulent; [uncommon exotic, SC s. to FL, w. to TX and AR]
(c) Montes de Oca, Joseph - CC-BY-NC, permission granted to NCBG
                                                        27 Flowers in dense, terminal, involucrate heads; flowers 4- or-6-lobed; styles 3
(c) Horn, Jay
(c) Shaw, Joey
                                                          28 Flowers usually solitary in leaf axils; fruit separating into 2 parts.
(c) Bradley, Keith
(c) Bradley, Keith
                                                          28 Flowers in terminal and axillary clusters; fruits not separating into 2 parts.