1 Leaves opposite (to subopposite).

..2 Branches armed, secondary branches (short shoots) thorn-tipped; Leaf margins serrulate, serrate, or crenate; leaf apex acuminate or acute; drupe with 2-4 stones; petals 4 or 5, white, cream, or yellow; [collectively widespread in our region].

....3 Leaves (2-) 4-10 (-13) cm long; inflorescence a fascicle or flower solitary; sepals 4; petals 4; flowers functionally unisexual (the stamens rudimentary in the pistillate flowers); [exotics, mainly inland and/or northwards in our area]

....3 Leaves 1.5-4 (-6) cm long; inflorescences a panicle-like thyrse; sepals 5; petals 5; flowers bisexual; [native, of the Coastal Plain]

..2 Branches unarmed; leaf margins entire; leaf apex either slightly to deeply notched or acute to acuminate; drupe with 1 stone; petals 5 or absent; [FL peninsula or TX].

......4 Leaf blades gland-dotted on the undersurface; petals 5; [TX]

......4 Leaf blades not gland-dotted; petals 0; [FL peninsula].

........5 Drupes 5-8 (-12) mm long; secondary veins borne mostly at a 50-75° angle to the midvein, and arching as they approach the margin; sepals crested on the upper surface

........5 Drupes 10-20 mm long; secondary veins borne mostly at a 70-90° angle to the midvein, and remaining straight before splitting Y-fashion as they approach the margin; sepals with a slight keel on the upper surface

1 Leaves alternate.

..........6 Plant a woody vine.

............ 7 Leaf margins serrate to crenate; leaf apex acute-acuminate; tendrils present; [of ne. FL southward]

..........6 Plant a shrub (sometimes clambering) or small tree.

............ ..8 Leaves with 3 (-5) prominent veins from near the base (and 1-3 additional pairs of veins along the midvein); leaf margins toothed (serrate or crenate).

............ ....9 Leaves 7-17 cm long; inflorescence repeatedly branched dichotomously; peduncles fleshy and reddish in fruit; nectariferous disc pubescent.

............ ....9 Leaves 0.2-10 cm long; inflorescence a fascicle, cyme, thyrse, umbel-like, or panicle-like; peduncles neither fleshy nor red; nectariferous disc glabrous.

............ ......10 Plants armed with stipular spines; fruit either fleshy (a drupe with 1 stone), or dry (a 1-seeded samara).

............ ........11 Fruit dry (a 1-seeded samara)

............ ........11 Fruit fleshy (a drupe with 1 stone)

............ ......10 Plants not spiny; fruit dry, a 3-locular capsular with many seeds; [tribal placement uncertain].

............ ..........12 Erect shrubs to 1.5 m tall; inflorescence panicle-like or umbel-like, with many flowers (> 20)

............ ..........12 Clambering shrub to 8 m tall; inflorescence 1 2-7-flowered thyrse or the flower solitary

............ ..8 Leaves either with prominently pinnate venation (the lowermost lateral veins no more prominent than others) or with no prominent lateral veins; leaf margins either entire or toothed (serrate or crenate).

............ ............ 13 Fruits dry, a 3-locular capsule with many seeds; ovary ½-inferior; branches unarmed

............ ............ 13 Fruits fleshy, a drupe with 1-4 stones; ovary superior; branches either unarmed, or armed with thorn-tipped secondary short shoots and sometimes also with stipular spines.

............ ............ ..14 Drupe with 1 stone; leaves 0.5-3 cm long, entire, 1-veined, the apex notched; branches armed with thorn-tipped secondary short shoots and sometimes also with stipular spines; [TX, peninsular FL]

............ ............ ....15 Leaves pinnately veined; drupes 3-6 mm in diameter; style 1; petals 0; [TX]

............ ............ ....15 Leaves with no venation apparent other than the midvein; drupes 5-10 mm in diameter; leaves with no venation apparent other than the midvein; style 2-4; petals 5; [TX or peninsular FL]

............ ............ ......16 Drupe yellow or orange (drying brownish); inflorescence a fascicle; petals white

............ ............ ......16 Drupe blue to purple, 5-10 mm long; inflorescence a thyrse on a short (1-2 mm) peduncle; petals yellow

............ ............ ..14 Drupe with 2-4 stones; leaves (2-) 4-13 cm long, toothed (serrate or crenate), with prominently pinnate venation, the apex acuminate, acute, or obtuse; branches unarmed; [collectively widespread].

............ ............ ........17 Winter buds naked, pubescent; flowers perfect, sepals, stamens, and petals 5; style undivided; leaves with 8-10 lateral veins on either side of the midvein

............ ............ ........17 Winter buds with bud scales; flowers functionally unisexual, sepals and stamens 4 or 5 (the stamens rudimentary in the pistillate flowers), petals 0 or 4 (never 5); style divided for 1/3 to 2/3 its length into 2, 4 or 5 segments; leaves with (2-) 3-9 lateral veins on either side of the midvein

1 Leaves serrate.

..2 Leaf venation palmate, the leaf often lobed or at least pentagonal in shape (as well as serrate); plants climbing by leaf-opposed tendrils

..2 Leaf venation pinnate, the leaf neither lobed nor pentagonal; plants climbing by other mechanisms (see below).

....3 Plants climbing by axillary tendrils; [FL]

....3 Plants climbing by adventitious roots, by twining, or by growing through bark layers of Taxodium ascendens or Chamaecyparis thyoides; [collectively widespread in our region].

......4 Plants climbing by adventitious roots; leaf base cordate or subcordate, and also slightly to strongly oblique

......4 Plants climbing by twining, or by growing through bark layers of Taxodium ascendens or Chamaecyparis thyoides; leaf base cuneate, rounded, or cordate.

........5 Leaves strongly cordate at the base, 7-15 cm wide

........5 Leaves cuneate, rounded, or subcordate at the base, 0.3-8 cm wide.

..........6 Leaf blades mostly 2-6 cm long, 0.3-2 cm wide; plants climbing by growing through bark layers of Taxodium ascendens or Chamaecyparis thyoides

..........6 Leaf blades mostly 6-13 cm long, 3-8 cm wide; plants climbing by twining

1 Leaves entire.

............ 7 Stems with well-developed prickles; tendrils paired, stipular (diverging from the leaf petiole above its base); [Monocots]

............ 7 Stems lacking prickles; tendrils either absent or (if present) not stipular and paired; [Eudicots or Basal Angiosperms].

............ ..8 Plant climbing by dense, reddish adventitious roots

............ ..8 Plant climbing by twining or by tendrils.

............ ....9 Plant climbing by tendrils

............ ....9 Plant climbing by twining.

............ ......10 Leaves elliptic or ovate, obviously longer than broad, most leaves > 1.4× as long as wide; leaf blade base narrowly cuneate, broadly cuneate, rounded, or subcordate.

............ ........11 Leaves 6-15 cm long, cuneate at the base and acuminate at the apex; lateral leaf veins forking at or beyond the middle; inflorescence a solitary, axillary flower

............ ......10 Leaves orbicular to very widely ovate, most leaves < 1.4× as long as wide; leaf blade base deeply cordate, subcordate, rounded, or broadly cuneate

............ ..........12 Leaf venation pinnate, but “pseudopalmate”, with 3 primary veins from the marginal point of attachment of the petiole, the 2 lateral veins then promptly rebranching (< 1 cm from the leaf base) into 2-3 prominent veins (the remainder of the venation pinnate along the midvein); basalmost pair of primary veins exposed (lacking leaf tissue) on their basal side for > 2 mm; leaf blade base deeply cordate; leaf with no tendency to lobing, the leaf outline convex from the base to the apex (except in the immediate vicinity of the petiole and sometimes immediately near a slightly acuminate apex

............ ..........12 Leaf venation palmate, with (3-) 5-9 primary veins from the marginal or peltate point of attachment of the petiole, these primary veins then rebranching well above the leaf base; basalmost pair of primary veins completely included within leaf tissue; leaf blade base cordate, subcordate, rounded, or broadly cuneate; leaf with a tendency to lobing, the leaf outline with 1 or more concave areas between the base and the apex (except Cissampelos of s. FL)