| |
| | 2. Corolla 15–25 mm; bract 2–5 cm; plant white-woolly |
| S. carduacea |
| | 2' Corolla 6–8 mm; bract < ± 1 cm; plant short-hairy |
| S. columbariae |
| |
| |
| | 4. Leaf white-woolly, short-petioled, generally deciduous, in 1–2 pairs or 0 on margins; calyx lobes triangular, white-woolly |
| S. funerea |
| | 4' Leaf green-tomentose, sessile or short-petioled, persistent, in 2–7 pairs on margins; calyx lobes lanceolate, not white-woolly |
| S. greatae |
| |
| | 5. Perennial; leaf ± green |
| |
| | 6. Corolla blue to pinkish purple, 6–15 mm |
| S. verbenacea |
| | 6' Corolla red to salmon or yellow, 10–35 mm |
| |
| | 7. Corolla yellow, 10–20 mm, upper lip arched; calyx white-woolly; cultivated, sometimes escaped |
| S. aethiopis |
| | 7' Corolla red to salmon, 25–35 mm, upper lip straight; calyx hairs short, white; native |
| S. spathacea |
| | 5' Shrub to perennial herb; leaf ± green to grayish white |
| |
| | 8. Stamens included to slightly exserted |
| |
| | 9. Leaf linear to linear-elliptic, margins rolled under, lower surface with branched hairs; heterostylous |
| S. brandegeei |
| | 9' Leaf oblong-elliptic to obovate, margins not or only slightly rolled under, lower surface with simple hairs; not heterostylous |
| |
| | 10. Corolla white to pale blue or lavender, rarely pale rose; flower clusters 1.6–4 cm wide; leaf oblong-elliptic to obovate |
| S. mellifera |
| | 10' Corolla dark blue; flower clusters 1–1.5 cm wide; leaf oblanceolate to obovate |
| S. munzii |
| |
| | 11. Lower corolla lip > 2 × upper; hairs simple |
| |
| | 12. Leaf grayish from ± bristly hairs or generally greenish; inflorescence generally < 5 dm |
| |
| | 13. Erect shrub; leaf linear; corolla white to pale lilac |
| S. eremostachya |
| | 13' Prostrate per; leaf lance-elliptic to obovate; corolla blue to lilac or purple |
| S. sonomensis |
| | 12' Leaf grayish velvety from minute appressed hairs; inflorescence generally > 10 dm |
| |
| | 14. Leaf base tapered; calyx lobes barely or not spine-tipped; flowers in ± spike-like clusters, these in ± raceme-like, interrupted panicles |
| S. apiana |
| | 14' Leaf base ± truncate to tapered; calyx lobes spine-tipped; flower clusters in ± spike-like, interrupted panicles |
| S. vaseyi |
| | 11' Lower corolla lip < 2 × upper; hairs simple or branched |
| |
| | 15. Width of lower middle corolla lobe < 1/2 length; leaf puckered, teeth rounded, hairs simple or branched, moderately dense to sparse, spreading |
| |
| | 16. Leaf base ± truncate to ± cordate; leaf ashy-gray, hairs branched; tissue between anther sacs glabrous |
| S. leucophylla |
| | 16' Leaf base tapered to ± truncate; leaf yellow- to gray-green, hairs simple; tissue between anther sacs glandular-hairy |
| |
| | 17. Bract dark, firm, < calyx; flower clusters 1–3 per flower stem |
| S. clevelandii |
| | 17' Bract pale, papery, >> calyx; flower clusters generally 1 per flower stem |
| S. mohavensis |
| | 15' Width of lower middle corolla lobe > or = length; leaf not puckered, ± entire, scaly or hairs simple, very dense, appressed |
| |
| | 18. Corolla blue-violet to rose, generally 13–23 mm; bract 10–20 mm; leaf 20–50 mm |
| S. pachyphylla |
| | 18' Corolla blue, rarely purple, rose, or white, generally 6–13 mm; bract 5–12(14) mm; leaf 4–30 mm |
| S. dorrii |
| | 19. Bract, calyx lower surface with soft shaggy hairs or scaly, margin hairs long |
| var. pilosa |
| | 19' Bract, calyx glabrous to scaly, margin hairs generally short |
| |
| | 20. Leaf abruptly narrowed to petiole, 6–20 mm, widest 2–13 mm from base |
| var. dorrii |
| | 20' Leaf tapered to petiole, 10–40 mm, widest 6–28 mm from base |
| var. incana
|