1 Fresh flowers orange, yellow, greenish-yellow, or greenish white (if greenish white, then the inflorescence a terminal many-branched cyme); [“North America clade”].

..2 Inflorescence a dense pom-pom-like raceme, terminating leafy branches.

....3 Fresh flowers lemon-yellow or greenish yellow; subulate bracts of the inflorescence 4.5-6.5 mm long; plants 3-10 (-15) cm tall; lobes of lower petal (keel) 1.5-2.5 mm long

....3 Fresh flowers bright orange or bright yellow; subulate bracts of the inflorescence 2-4 mm long; plants 5-80 cm tall; lobes of lower petal (keel) 0.5-1.1 mm long.

......4 Racemes ca. 15 mm in diameter; flowers bright orange (rarely individual plants within a population with bright yellow flowers); plants 5-40 cm tall; [more widespread]

......4 Racemes ca. 25 mm in diameter; flowers bright yellow; plants 30-80 cm tall; [of FL]

..2 Inflorescence a terminal, many-branched cyme, the many individual branches loosely to densely flowered.

........5 Fresh flowers cream-white to greenish-white; [of GA southward].

..........6 Inflorescence of dense racemes; wings white (drying darker), 0.9-1.4 mm wide, the apical cusp 0.6-0.8 mm long; seeds < 0.6 mm long; aril of seeds usually ca. 0.2 mm long; [more widespread]

..........6 Inflorescence of elongated racemes; wings cream to greenish-white (drying darker), 1.5-1.7 mm wide, the apical cusp 0.3-0.5 mm long; seeds usually 0.6-0.7 mm long; aril of seeds a minute scale or absent; [of s. FL]

........5 Fresh flowers bright yellow; [collectively widespread in the Coastal Plain of our area].

............ 7 Plants 4.5-12 dm tall, the stem solitary; basal leaves 3.5-14 cm long, linear-lanceolate, about 15-20× as long as wide, persistent as a basal rosette; stem leaves linear-subulate, sharp-tipped, much reduced from the basal leaves, becoming bractlike upward; seeds glabrous, 0.7-0.9 mm long

............ 7 Plants 1-4 dm tall, the stems 1-several from the base; basal leaves 3-7 cm long, spatulate, about 10× as long as wide, usually not persistent after flowering; stem leaves narrowly spatulate to linear, blunt-tipped, only slightly reduced from the basal leaves; seeds pubescent, 0.5-0.7 mm long

1 Fresh flowers pink, purple, white, or green (if green or white, then the inflorescence a simple raceme, not a many-branched cyme).

............ ..8 Leaves many, evenly distributed along the stem, or not at least strongly clustered near the tip; wings < 10 mm long; stamens 8; [collectively of a wide variety of habitats, but generally not as above, either in more open, drier, or non-montane habitats].

............ ....9 Leaves whorled, at least at the principal lower nodes; annual, from a slender taproot.

............ ......10 Racemes 3-8 mm in diameter, pointed in outline; flowers sessile to pedicellate with pedicels < 1 mm long; [“Verticillatae clade"].

............ ........11 Wings 2-3 mm long; plant perennial, usually multistemmed from the base and little or not branched above; racemes 30-240 mm long.

............ ..........12 Lowermost leaves elliptic to suborbicular; branches ascending to erect; [s. FL north and west to GA, TN, MS, and w. LA]

............ ..........12 Lowermost leaves linear to linear-lanceolate; branches decumbent to spreading; [s. FL]

............ ........11 Wings 1-1.75 mm long; plant annual, unbranched or freely branched above.

............ ............ 13 Internodes > 5 cm long, the whorls very distant from one another; seeds glabrous or nearly so; seeds fusiform

............ ............ 13 Internodes (most, at least) < 4 cm long; seeds pubescent; seeds ovoid to narrowly ovoid.

............ ............ ..14 Racemes 2-5 cm long, becoming interrupted below through persistence of the fruits on the axis; wings equaling the fruit

............ ............ ..14 Racemes 0.5-1.5 cm long, the fruits falling promptly, thus the inflorescence compact and truncate below; wings shorter than the fruit.

............ ............ ....15 Seeds finely pubescent; pedicels 1/4-1/3 as long as the fruit; raceme peduncles 0.5-4 cm long

............ ............ ....15 Seeds hirsute; pedicels 1/3-1/2 as long as the fruit; raceme peduncles 2-7 cm long

............ ......10 Racemes 7-20 mm in diameter, rounded in outline (somewhat rounded to somewhat pointed in P. hookeri); flowers pedicellate; [“North America clade”].

............ ............ ......16 Racemes loosely flowered, with ca. 10 flowers per cm of length; raceme 7-12 mm in diameter, the tip pointed (obconical) in outline; full raceme (including the portion with dropped fruits) to 6 cm long

............ ............ ......16 Racemes densely flowered, with ca. 20 flowers per cm of length; raceme 7-20 mm in diameter, the tip rounded to truncate in outline; full raceme (including the portion with dropped fruits) to 4.5 cm long.

............ ............ ........17 Bracts of the inflorescence ca. 1 mm long; wings 1.5-2.5 mm wide, acute or short-mucronate at the tip; raceme peduncle (0.8-) 3-5 cm long

............ ............ ........17 Bracts of the inflorescence 1.5-3 mm long; wings 3-4 mm wide, acuminate, the tips cuspidate; raceme peduncle 0-0.8 (-4) cm long

............ ............ ..........18 Peduncle + axis length (10-) avg. 16 (-23) mm (in late flower or fruit); raceme (8.5-) avg. 9.9 (-12) mm wide

............ ............ ..........18 Peduncle + axis length (11-) avg. 35 (-96) mm (in late flower or fruit); raceme (10-) avg. 12 (-15) mm wide

............ ....9 Leaves all alternate; either annual, from a slender taproot, the stems solitary, or biennial to perennial, from a taproot, the stems solitary to several, or perennial, from a thick rhizome, the stems several.

............ ............ ............ 19 Leaves glaucous, somewhat succulent, linear; corolla 7-10 mm long, > 2× as long as the wings; [“North America clade”]

............ ............ ............ 19 Leaves green, herbaceous, usually broader than linear; corolla < 5 mm long, roughly equal to or shorter than the wings.

............ ............ ............ ..20 Leaves reduced to subulate scales < 2 mm long; [e. GA west to MS, south to s. FL]; [“North America clade”]

............ ............ ............ ..20 Leaves (at least the larger) > 2 mm long, not subulate; [collectively widespread].

............ ............ ............ ....21 Perennial or biennial, usually several stems arising together from a rhizome or taproot.

............ ............ ............ ......22 Wings white, 2-3 mm long; flowers sessile or subsessile; plants from a thick crown; [“Linoideae clade"].

............ ............ ............ ........23 Larger leaves mostly 15-35 mm wide; capsules 3.5-4.2 mm long; seeds 3.0-3.5 mm long

............ ............ ............ ........23 Larger leaves mostly 2-15 mm wide; capsules 2.5-3.5 mm long; seeds ca. 2.5 mm long

............ ............ ............ ......22 Wings pink, 4-7 mm long; flowers pedicelled; plants from a taproot.

............ ............ ............ ..........24 Corolla keel entire at the tip; wings 5-7 mm long, reniform-orbicular; plants lacking cleistogamous flowers

............ ............ ............ ..........24 Corolla keel fringed at the tip; wings 4-6 mm long, elliptic; plants producing cleistogamous flowers in loose subterranean or surficial racemes; [“North America clade”]

............ ............ ............ ....21 Annual, the stems solitary; [“North America clade”].

............ ............ ............ ............ 25 Corolla about 0.5× as long as the wings

............ ............ ............ ............ 25 Corolla about 1× as long as the wings.

............ ............ ............ ............ ..26 Inflorescence bracts dropping from the axis promptly following flowering

............ ............ ............ ............ ..26 Inflorescence bracts persistent.

............ ............ ............ ............ ....27 Wings 3-5 mm long; pedicels 1.5-2.5 mm long; racemes 8-13 mm in diameter

............ ............ ............ ............ ....27 Wings 2-2.5 mm long; pedicels 0.5-1.5 mm long; racemes 5-6 mm in diameter

1 Corolla keel blunt, lacking a terminal crest or beak.

..2 Calyx persistent in fruit

..2 Calyx deciduous in fruit

1 Corolla keel appendaged, with a terminal beak, or lobed or tufted crest.

....3 Corolla keel with a conic or cylindrical beak

....3 Corolla keel with a lobed or tufted crest.

......4 Flowers in terminal spikes, racemes, or corymbs; plants annual or perennial