1. Stamens > in number than corolla lobes
2. Lf compound — petals proximally free but strongly adherent and may appear fused ..... FABACEAE (Papilionoideae)
2' Lf simple, sometimes reduced to linear or scale-like bracts
3. Filaments fused, forming a U-shaped tube around the style — petals actually free but may appear fused ..... POLYGALACEAE {G15,22,23,24}
3' Filaments free
4. Shrub; leaves alternate; anthers dehiscing by pores; ovules many; fruit a capsule ..... ERICACEAE (Rhododendron macrophyllum)
4' Herb or weak-stemmed subshrub; leaves opposite; anthers dehiscing by lateral slits; ovule 1; fruit an achene tightly enwrapped by hardened base of corolla-like calyx — petals actually 0 but sepals petal-like and involucre bracts sepal-like ..... NYCTAGINACEAE (Allionia)
1' Stamens = in number to corolla lobes or fewer
5. Corolla scarious, persistent in fruit ..... PLANTAGINACEAE (Plantago) {G5,8,19}
5' Corolla not scarious, generally deciduous after flower
6. Fertile stamens = in number to corolla lobes
7. Ovary deeply 4-lobed, especially in fruit; style attachment surrounded by lobes of ovary (style readily detaches in Lamiaceae as corolla falls); fruit breaking apart into 1-seeded nutlets (sometimes only 1–3 nutlets maturing)
8. St round in ×-section; leaves alternate (proximal opposite in some Plagiobothrys); herbage not aromatic; inflorescence or inflorescence branches coiled when young, unrolling in flower or fruit ..... BORAGINACEAE {G19}
8' St 4-angled, at least when young; leaves opposite throughout; herbage generally strongly aromatic, especially if crushed; inflorescence or inflorescence branches not coiled ..... LAMIACEAE (3) {G8,19}
7' Ovary entire or shallowly lobed; style clearly attached to tip of ovary; fruit a capsule or splitting into nutlets
9. Shrub; filaments attached directly to receptacle, falling free from corolla or only weakly adhering; anthers dehiscent by pores ..... ERICACEAE {G17,19,24}
9' Herb; filaments fused to and falling with corolla; anthers dehiscent by slits
10. Calyx lobes bordered by or ± fused by a much thinner, transparent or translucent membrane; corolla generally funnel-shaped to salverform; stigmas 3; ovary chambers 3 ..... POLEMONIACEAE {G19}
10' Calyx lobes not bordered by or fused by transparent or translucent membrane; corolla ± rotate; stigmas 1–2; ovary chambers 1–4
11. Corolla white to blue or purple, 2–8 mm diam; inflorescence cyme-like, or flowers solitary; fruit splitting into generally 4 one-seeded nutlets ..... BORAGINACEAE (Tiquilia) {G19}
11' Corolla yellow (white to ± purple), 15–40 mm diam; inflorescence a narrow raceme or panicle; fruit a many-seeded capsule ..... SCROPHULARIACEAE (Verbascum) {G19}
6' Fertile stamens fewer than corolla lobes — 1 or more sterile stamens sometimes present
12. Plant entirely non-green, ± fleshy ..... OROBANCHACEAE (2)
12' Plant green and photosynthetic
13. Proximal portion of lower corolla lip with backward-projecting, conic or tubular spur
14. Plant aquatic; leaf-like underwater stems generally dissected, generally submersed, generally bearing small, hollow bladders that suck in and trap small organisms when hairs at opening are triggered ..... LENTIBULARIACEAE (Utricularia) {G2}
14' Plant terrestrial; leaves entire to shallowly lobed, without hollow bladders
15. Lvs all basal; adaxial leaf face sticky or slimy with insect-capturing glands ..... LENTIBULARIACEAE (Pinguicula)
15' Lvs basal and cauline or all cauline; adaxial leaf surface not sticky or slimy with insect-capturing glands ..... PLANTAGINACEAE (4) {G5,19}
13' Proximal portion of lower corolla lip without backward-projecting, conic or tubular spur, occasionally with expanded pouch
16. Ovary generally deeply 4-lobed; style attachment surrounded by lobes of ovary [style readily detaches as corolla falls] — fruit breaking into 4 one-seeded nutlets ..... LAMIACEAE (3) {G8,19}
16' Ovary entire or ± shallowly lobed; style arising from tip of ovary
17. Ovules 1–4 per ovary chamber
18. Fr a capsule
19. Shrub ..... ACANTHACEAE
19' Annual ..... PLANTAGINACEAE (4) {G5,19}
18' Fr 2–4 nutlets
20. Stamens exserted ..... LAMIACEAE (3) {G8,19}
20' Stamens included ..... VERBENACEAE {G19}
17' Ovules several to many per ovary chamber
21. Lvs compound ..... BIGNONIACEAE (2)
21' Lvs simple
22. Capsule 5–35 cm
23. Shrub or tree; capsule body 15–35 cm, straight, linear ..... BIGNONIACEAE (2)
23' Annual; capsule body 5–10 cm, curved, tipped with a hooked beak several cm long ..... MARTYNIACEAE
22' Capsule < 2 cm
24. Corolla upper lip forming a concave beak or hood, ± enclosing or covering stamens and style
25. Sterile stamen 0; lobes of upper corolla lip obscure or 0 ..... OROBANCHACEAE (2)
25' Sterile stamen present, inserted on corolla tube between lobes of upper corolla lip; lobes of upper lip evident ..... PLANTAGINACEAE (4) {G5,19}
24' Corolla upper lip not forming a beak or hood, not enclosing or covering stamens and style [though these may be included within corolla tube or throat]
26. Stigma lobes flat, disk-like, moving together when touched; cauline leaves opposite ..... PHRYMACEAE {G2,19}
26' Stigma dot-like or head-like, unlobed, or lobes not moving together when touched; cauline leaves opposite or alternate (whorled) or leaves all basal
27. Lvs all basal
28. Fls solitary; stamens 4; leaves linear or awl-like to spoon-shaped or ovate, entire ..... SCROPHULARIACEAE (Limosella) {G2,19}
28' Fls in raceme; stamens 2; leaves ovate to round, toothed or shallowly lobed ..... PLANTAGINACEAE (Synthyris)
27' Lvs basal and cauline or all cauline
29. St 4-angled; corolla tube urn-shaped to spheric ..... SCROPHULARIACEAE (Scrophularia)
29' St generally round in ×-section; corolla tube cylindric to bell-shaped, sometimes very short ..... PLANTAGINACEAE (4) {G5,19}
