X
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.

Click images to enlarge and show more photo credit.

Key to Rutaceae

Rutaceae

Copy permalink to share

1 Herbs, becoming somewhat woody at the base, < 1 (exceptionally to 1.4) m tall; [subfamily Rutoideae].
  2 Leaves 2-pinnatifid, with many segments; [exotic, grown horticulturally, scattered as persistent or weakly naturalized]
  2 Leaves simple; [native in calcareous grasslands and woodlands in ne. and c. TX westwards and southwards]
1 Shrubs and trees, definitely woody, > 1 m tall when mature (flowering and fruiting).
    3 Leaves either simple, or unifoliolate and appearing simple.
      4 Stems unarmed, inflorescence axes and young stems with short, red-brown, scurfy hairs; inflorescences of short, compact to somewhat elongate racemes; [subfamily Aurantioideae; Bergera alliance]
      4 Stems armed or unarmed, inflorescences and young stems glabrous, or pubescent with short, grey to white, erect to curved hairs; inflorescences of small fascicles, or solitary or paired flowers; [subfamily Aurantioideae; Citrus alliance].
        5 Hesperidia bluish black when ripe, 0.8-1.2 cm in diameter; stamens 10; petiole not winged; stems armed; abaxial leaf surface with raised lateral veins; petals < 0.5 cm long
        5 Hesperidia green, yellow, or orange when ripe, > 1.5 cm in diameter; stamens 20+; petiole usually winged; stems armed or unarmed; abaxial leaf surface without raised lateral veins; petals > 1 cm long
    3 Leaves pinnately or palmately compound (1-foliolate leaves sometimes also present).
          6 Leaves 1-pinnate, either odd-pinnate and (3-) 5-19-foliolate or even-pinnate and (4-) 6-8 (-14)-foliolate.
             7 Leaves opposite; stems and leaves unarmed.
(c) Conboy, Andrew - CC-BY
               8 Axillary buds concealed beneath the base of the petioles on mature, leafy stems; leaflets (7-) 9-13; bark on older stems corky; [subfamily Zanthoxyloideae]
               8 Axillary buds exposed above the base of the leaf petioles on mature, leafy stems; leaflets 3-9 (-11); bark on older stems smooth to somewhat rough but never corky.
                 9 Fruit a drupe; diameter of mid-point of internodes of leafy branches usually 1-3 mm; internode lenticels usually < 0.3 mm long, mostly round (or absent); [native in FL and TX, and also planted and escaped in FL]; [subfamily Amyridoideae]
                 9 Fruit of 1-5 follicles; diameter of mid-point of internodes of leafy branches usually 3-6 mm; internode lenticels usually > 0.4 mm long and round to elongate; [planted and escaped in more northern parts of our area]; [subfamily Zanthoxyloideae]
             7 Leaves alternate; stems and leaves either unarmed, or armed with prickles.
                   10 Leaflets alternate on the rachis; fruit a berry, orange to red when ripe; stems and leaves unarmed; [subfamily Aurantioideae]
                   10 Leaflets opposite on the rachis; stems either not armed (Glycosmis) or stems (and also often leaves) armed with prickles (Zanthoxylum, except Z. flavum).
                     11 Fruit of 1-5 follicles; [subfamily Zanthoxyloideae]
(c) Sorrie, Bruce A. - CC-BY
          6 Leaves palmately 3-foliolate.
                       12 Branches armed with axillary spines; fruit a hesperidium; [subfamily Aurantioideae].
                          13 Petiole winged; stamens 20+; hesperidia 4-5 cm in diameter, dark yellow to orange when ripe, densely pubescent, usually with > 20 seeds (looking like a small, hairy orange)
                          13 Petiole not winged; stamens 6-10; hesperidia 1-1.5 cm in diameter, glabrous, red when ripe, with 1-4 seeds; spines usually paired at nodes; petals often 3
                            14 Fruit a drupe or few-seeded berry; [subfamily Amyridoideae]
Click images to enlarge and show more photo credit.

Key F1: Key to Plantae

Copy permalink to share | Check for keys that lead to this key

1 Leaves 1- or 2-foliolate, if 1-foliolate then deeply notched and appearing bilobed (Bauhinia, which is also keyed in Key G).
  2 Leaves 1-foliolate (bilobed)
  2 Leaves 2-foliolate
    3 Leaflets elliptic to lanceolate, acute at the apex; petals white, not clawed; fruit a pinkish-red berry, mucilagenous or dry at maturity; plants shrubs
    3 Leaves cordate and deeply cleft (appearing 2-foliolate) or if subtly 2-foliolate, the lobes rounded at the ends; petals pink, clawed; fruit an elongated legume; plants shrubs or sometimes vines
1 Leaves 3-, 5-, to many-foliolate.
        5 Leaves untoothed and unlobed; fruit a legume
        5 Leaves coarsely toothed or lobed; fruit a berry (except legume in Pueraria)
          6 Leaflets obovate or broadly elliptic (broadest at or above the middle), the teeth or lobes soley or primarily in the apical half of the leaf; plant climbing by tendrils; fruit a blue to black berry.
             7 Plants with leaves trifoliolate only, the blades fleshy, > 1 mm thick when fresh, the leaftlets ovate to oblong; inflorescence axillary (accompanying leaves, not opposing them); [tribe Cayratieae]
             7 Plants often with a mix of well-developed trifoliate leaves and (less-developed) tri-lobed, simple leaves (the lobes or leaflets broadly ovate to ovate-reniform), these herbaceous, the blades thin; inflorescence leaf-opposed; [tribe Cisseae]
          6 Leaflets orbicular or ovate (broadest at the middle or below the middle), the teeth or lobes primarily or solely in the basal half of the leaf; plant climbing by stem twining or by dense, reddish adventitious roots; fruit a legume (Pueraria) or whitish berry (Toxicodendron).
               8 Plant climbing by the stem twining; [plant not actually woody, but so robust as to often be assumed to be so]
               8 Plant climbing by dense, reddish adventitious roots attaching the stem to tree trunks or rock outcrops
      4 Plant a shrub or small tree (sometimes scrambling or occasionally high-climbing with the support of other vegetation, but lacking the specialized climbing structures listed above, e.g., Akebia).
                   10 Stems with stout thorns at the nodes; fruit a hesperidium (orange-like, but densely hairy)
                   10 Stems with many small prickles along the internodes (directly below the nodes; sometimes inconspicuous on the vegetative stems of Erythrina); fruit various: either a legume, berry, an aggregate of drupelets, or a hip.
                     11 Leaflet bases cuneate to rounded, unlobed (sometimes cleft), but lacking 2 rounded, lateral lobes at their bases; fruit either a drupe (Eleutherococcus), berry (Triphasia), OR a hip or aggregate of drupelets (ROSACEAE); corolla variously colored.
                       12 Flowers 3-merous (sometimes with 4 or rarely with 5 petals); fruit a glabrous berry, reddish when ripened; [uncommon non-native, s. FL]
                       12 Flowers 4- or 5-merous (with 4 or 5 petals); fruit a drupe, an aggregate of drupes, or a hip; [collectively widespread natives and non-natives, including s. FL].
                          13 Inflorescence a compound umbel, notably rounded in shape; leaves 3-5-foliolate (often trifoliolate, sometimes palmately compound); fruit a drupe; [uncommon non-native, n. FL]
                          13 Inflorescence a panicle, not notably rounded in shape; leaves 3 or more foliolate; fruit an aggregate of drupelets or a hip; [natives and non-natives; widespread]
                            14 Leaflets serrulate, crenulate, serrate, with a few coarse and jagged teeth (spine-tipped or not), or shallowly lobed (Erythrina).
                                16 Leaflets 3-11 (usually 5+ per leaf, also keyed in F5); fruit a fleshy berry, red to dark orange at maturity; [uncommon non-native, s. FL]
                                16 Leaflets usually 3 (leaves typically trifoliolate); fruit a conspicuously winged samara (dry at maturity), greenish-brown at maturity; [natives, c. FL northward and westward]
                              15 Leaflets serrate, with a few coarse and jagged teeth (spine-tipped or not), or shallowly lobed (Erythrina).
                                  17 Leaflets with 2 prominent, rounded lobes near the base; fruit a legume; flowers > 3 cm long, corollas bilaterally symmetrical, red, in a terminal raceme
                                  17 Leaflets serrate and sometimes also cleft, or with a few coarse and jagged teeth (spine-tipped or not); fruit either a tan or red drupe or a red berry; flowers < 1 cm across, corollas radially symmetrical, green, yellow, or white, in axillary or terminal panicles or racemes
                                         20 Leaflets 2-5 cm long (Hypelate) or 5-15 cm long (Ptelea); stems and branches tan to brown
                                           21 Leaflets obovate to oblanceolate, the apices usually rounded; leaves 2-5 cm long, often congested at branch tips; fruit a fleshy drupe, maroon or black-colored when ripened; flowers arranged in panicles; [s. FL only in our area]
                                           21 Leaflets usually ovate, the apices acute or acuminate; leaves 5-15 cm long, usually spaced throughout the stems, rarely congested at leaf tips; fruit a samara, brown when ripened; flowers arranged in cymes; [c. FL northward, widespread]
                                             22 Fruit a berry, a berry-like drupe, or a legume (not valvate but often dehiscent); leaves lacking a strong scent of horseradish.
                                               23 Petals white, small (ca. 4 mm long); fruit a pinkish-red berry, mucilagenous or dry at maturity
                                               23 Petals small to large, variously colored (including white); fruit a legume or if berry like, then white at maturity, often somewhat laterally flattened, and plants vining, rhizomatous shrubs (Toxicodendron).
                                                 24 Leaves pinnately trifoliolate, a rachis present as an extension of the petiole past the point of attachment of the 2 lateral leaflets, the terminal leaflet borne on a petiolule at the terminus of the rachis, with an obvious joint present between the rachis and petiolule; fruit a legume
                                                 24 Leaves palmately trifoliolate, the terminal leaflet typically with a longer petiolule than the lateral leaflets, but lacking a rachis (the petiolule of the terminal leaflet attached at the same point as the 2 lateral leaflets and unjointed); fruit a white, berry-like drupe (globose or often laterally somewhat flattened).