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1 Leaves tiny, bract-like, triangular, 6-14 (-17) per node |
1 Leaves either needle-like, scale-like, or flattened and large, (2-) 3-4 (-6) per node. |
..2 Leaves needle-like or scale-like, terete, angled, or flat in ×-section, < 2 cm long; leaves (2-) 3-4 (-6) per node |
..2 Leaves flat, > 3 cm long; leaves (2-) 3 per node; [Eudicots]. |
....3 Plant a subshrub, < 3 dm tall, with < 10 leaves per stem. |
......4 Leaves entire, broadly elliptic; flowers numerous, in a hemispherical head, subtended by 4 large white bracts |
......4 Leaves serrate, narrowly ovate or narrowly obovate; flowers (1-) 2-8 in a long-peduncled umbel or corymb, not subtended by bracts |
....3 Plant a shrub or tree, > 3 dm tall, with many > 10 leaves per stem. |
........5 Leaves toothed, and most leaves also lobed |
........5 Leaves entire, not lobed. |
..........6 Leaves cordate at base; leaves about as long as wide; medium to large tree. |
............ 7 Flowers white to yellow; capsules linear, >10× as long as wide; leaf undersurface with curly simple hairs; nectar glands present in the main vein axils on the undersurface of the leaf (visible from the underside or the upperside in fresh leaves and herbarium specimens as a triangle 1-4 mm on a side) |
............ 7 Flowers lavender; capsules ellipsoid, < 2× as long as wide; leaf undersurface with branched (dendritic or stellate) hairs; nectar glands absent |
..........6 Leaves cuneate to rounded at base; leaves > 1.5× as long as wide; shrub to small tree. |
............ ..8 Leaves rounded at the tip |
............ ..8 Leaves acute to acuminate at the tip. |
............ ....9 Leaves lanceolate or oblong-elliptic (> 2.5× as long as wide), the secondary venation not prominent; inflorescences axillary or terminal; flowers pink or white. |
............ ......10 Inflorescences axillary; flowers pink; leaves thin and herbaceous; [native plants of wetlands] |
............ ......10 Inflorescences terminal or axillary; flowers pink or white; leaves thick and leathery; [exotics of uplands or wetlands, persistent or weakly naturalized] |
............ ........11 Fruit berry-like with 2-locular ovaries; flowers white-colored, smaller; inflorescence axillary or pseudo-terminal; leaves opposite to whorled |
............ ........11 Fruit follicles; flowers variously colored, showy and salverform; inflorescence terminal; leaves alternate to whorled (pseudo-whorled) |
............ ....9 Leaves ovate (< 2× as long as wide), the secondary venation prominent and arching-parallel; inflorescences terminal; flowers white, greenish-yellow, red, or orange. |
............ ..........12 Flowers in a spherical or hemispherical head; corollas white or greenish-yellow |
............ ..........12 Flowers in a monochasial helicoid cyme; corollas red to orange |
1 Leaves pinnately lobed. |
..2 Leaves harshly scabrous on the upper surface; leaves typically a mix of alternate, opposite, and whorled |
..2 Leaves glabrous or glabrescent on the upper surface; leaves strictly opposite |
1 Leaves palmately lobed. |
....3 Plants climbing by twining; stems with retrorse prickles; foliage scabrous |
....3 Plants erect trees or shrubs; stems not prickly; foliage smooth or pubescent, but not scabrous. |
......4 Leaves 3-9-lobed, the margins generally serrate or sublobed; fruit either a drupe or a schizocarp of 2 samaroid mericarps (maple “keys”). |
........5 Fruit a schizocarp of 2 samaroid mericarps (maple “keys”); stamens (4-) 8 (-12); small to large trees; petioles >1× as long as the leaf blade |
........5 Fruit a drupe; stamens 5; shrubs; petioles < ¾× as long as the leaf blade |
......4 Leaves 3-lobed, the margins entire; fruit a capsule. |
..........6 Flowers white to yellow; capsules linear, >10× as long as wide; leaf undersurface with curly simple hairs; nectar glands present in the main vein axils on the undersurface of the leaf (visible from the underside or the upperside in fresh leaves and herbarium specimens) |
..........6 Flowers lavender; pods ellipsoid, < 2× as long as wide; leaf undersurface with branched (dendritic) stellate hairs; nectar glands absent |
1 Leaves deciduous (medium to pale green, thin in texture); leaves strictly opposite. |
..2 Leaves 10-70 cm wide, cordate or subcordate at the base; flowers 5-merous, bilaterally symmetrical, large (20-70 mm long), the petals connate into a tube; fruit a capsule. |
....3 Flowers white to yellow; capsules linear, >10× as long as wide; leaf undersurface with curly simple hairs; nectar glands present in the main vein axils on the undersurface of the leaf (visible from the underside or the upperside in fresh leaves and herbarium specimens as a triangle 1-4 mm on a side) |
....3 Flowers lavender; capsules ellipsoid, < 2× as long as wide; leaf undersurface with branched (dendritic or stellate) hairs; nectar glands absent |
..2 Leaves 1-12 cm wide, cuneate to rounded at the base; flowers 4-6-merous, radially symmetrical, small to medium (< 25 mm long), the petals either connate into a tube or separate and clawed; fruit a drupe or capsule. |
......4 Leaves with prominently parallel-arcing secondary veins; corolla 4-merous, < 8 mm long, white to cream; inflorescence a many-flowered corymb or head; flowers white to cream; fruit a drupe |
......4 Leaves with complexly branching secondary and tertiary veins; corolla 5-6-merous, 12-25 mm long, either greenish-yellow and mottled with purple, or white, pink, or purple; inflorescence a few-flowered cyme or many-flowered cymose panicle; fruit a capsule. |
........5 Leaves 4-20 cm long, 2.5-12 cm wide; petals connate into a 15-25 mm long tube, either greenish-yellow and mottled with purple; some calyx lobes expanding to 7 cm long and 5 cm wide, petaloid (pink to yellowish); capsule 2-valved; [native, in saturated, boggy seepages and streamheads, se. SC to FL] |
........5 Leaves 2.5-7 cm long, 1.5-4 cm wide; petals separate, clawed, 12-20 mm long (including the 6-9 mm long claw), white, pink, or purple; calyx remaining small and sepaloid (3.5-5 mm long); capsule 4-6-valved; [introduced, persistent from planting in upland to moist situations] |
1 Leaves evergreen (dark green or gray-green, thick in texture); leaves opposite or subopposite (offset by < 2mm from the opposing leaf). |
..........6 Mangroves, with one of various adaptations to growing in tidal or near-tidal, saline situations: prominent salt-excreting glands on the petiole ( Laguncularia in COMBRETACEAE), or prop roots ( Rhizophora in RHIZOPHORACEAE), or abundant pneumatophores ( Avicennia in ACANTHACEAE); [FL and less commonly subtropical shores of other, especially Gulf Coast, southeastern states]. |
............ 7 Leaves broadly elliptic, light green on both surfaces, rounded to broadly cuneate at the base, rounded and often retuse at the tip; petiole with 2 prominent salt-excreting glands; plants with neither prop-roots from the trunk and branches, nor pneumatophores from the roots |
............ 7 Leaves narrowly elliptic, dark green above, cuneate at the base, acute to obtuse at the tip; petiole without salt glands; plants with either prop-roots from the trunk and branches, or pneumatophores from the roots. |
............ ..8 Plants with numerous pneumatophores ascending from the roots and terminating in a blunt tip; leaves gray on the undersurface |
............ ..8 Plants with prominent prop-roots descending to the ground from the trunk and branches; leaves light green on the undersurface |
..........6 Non-mangroves; [collectively widespread]. |
............ ....9 Secondary leaf veins relatively few, further branching and reticulating into the tertiary vein structure; [collectively widespread]. |
............ ......10 Leaves strictly opposite, blue- or gray-green on both surfaces, suborbicular (about as wide as long), strongly aromatic when fresh |
............ ......10 Leaves opposite or subopposite (offset by < 2mm from the opposing leaf); dark green above, pale green below; oblancolate, elliptic, or ovate (distinctly longer than wide), not aromatic when fresh |
............ ........11 Twigs with spines; leaf venation with 3 primary veins from near the blade base; fruit a spherical berry, 5-12 cm long |
............ ........11 Twigs lacking spines; leaf venation pinnate; fruit an elliptical drupe, < 2.5 cm long |
............ ....9 Secondary leaf veins very many, closely parallel to one another and extending unbranched to the leaf margin. |
............ ..........12 Leaves elliptic, widest near the midpoint of the blade, ca. 2× as long as wide; flowers in axillary thyrses; fruit a 1-seeded drupe, 2-4 cm long |
............ ..........12 Leaves spatulate, widest towards the broadly rounded tip, ca. 1.2-1.6× as long as wide; flowers terminal on the branches, 1-3; fruit a leathery capsule, (4-) 6-9 (-12)-valved, 5-8 cm long |