| 1. Perennial (sect. Siphonella) |
| |
| L. floribundus subsp. hallii |
| 2' Leaf generally palmately lobed |
| |
| 3. Leaf lobes generally 3; pedicels generally 16 mm |
| L. floribundus |
| subsp. floribundus |
| 4' Leaf and calyx glabrous |
| subsp. glaber |
| 3' Leaf lobes generally 5; pedicels 0 or obscure |
| |
| 5. Leaf lobes linear-lanceolate; corolla tube generally > calyx; seeds > 2 mm; High Sierra Nevada |
| L. pachyphyllus |
| 5' Leaf lobes generally linear; corolla tube < calyx; seeds < 2 mm; not High Sierra Nevada |
| L. nuttallii |
| 6. Leaf and calyx sparsely hairy; Northwestern California, Modoc Plateau |
| subsp. nuttallii |
| 6' Leaf, calyx densely hairy |
| |
| 7. Leaf lobes 37 mm; High North Coast Ranges |
| subsp. howellii |
| 7' Leaf lobes 510 mm; East of Sierra Nevada |
| subsp. pubescens |
| |
| 8. Corolla salverform, tube >> calyx, < 1 mm wide; inflorescence a dense bracted head (sect. Leptosiphon) |
| |
| 9. Calyx membrane generally as wide as ribs |
| |
| 10. Bract margins densely white-ciliate; inflorescence generally spheric |
| |
| 11. Corolla tube generally < 25 mm, lobes 24 mm |
| L. ciliatus |
| 11' Corolla tube generally > 25 mm, lobes 58 mm |
| L. montanus |
| 10' Bract margin not white-ciliate; inflorescence generally not spheric |
| |
| 12. Leaf lobes oblanceolate; corolla lobes generally truncate or slightly notched at tip; corolla tube white; s High Sierra Nevada |
| L. oblanceolatus |
| 12' Leaf lobes linear or linear-lanceolate; corolla lobes rounded; corolla tube darker than lobes; more widespread s California, including s High Sierra Nevada |
| |
| 13. Lobes of bracts free; Transverse Ranges, sw Mojave Desert |
| L. breviculus |
| 13' Lobes of bracts connected by a translucent membrane; s Sierra Nevada |
| L. nudatus |
| 9' Calyx membrane << ribs or obscure |
| |
| 14. Corolla tube < 10 mm, < 2 × calyx length; corolla lobes white, throat dark purple |
| L. serrulatus |
| 14' Corolla tube > 10 mm, 26 × calyx length; corolla lobes variously colored, if white then throat not purple |
| |
| 15. Corolla yellow; leaf lobes needle-like, generally ascending |
| L. acicularis |
| 15' Corolla tube or lobes (not both) yellow; leaf lobes linear-lanceolate or oblanceolate, generally spreading |
| |
| L. bicolor |
| |
| 17. Calyx generally hairy only on lobe margins; North Coast Ranges, San Francisco Bay Area |
| L. androsaceus |
| 17' Calyx generally hairy throughout; widespread |
| L. parviflorus |
| 8' Corolla not both salverform and in dense bracted heads |
| |
| 18. Corolla 1530 mm; inflorescence a dense, bracted head (sect. Pacificus) |
| L. grandiflorus |
| 18' Corolla < 15 mm, or if > inflorescence not a dense, bracted head |
| |
| 19. Corolla generally open only in evening (if open in daytime, then limb > 10 mm wide); calyx membrane > ribs; corolla lacking red marks near throat (sect. Linanthus) |
| |
| 20. Calyx glandular-hairy |
| L. jonesii |
| 20' Calyx sometimes hairy but not glandular |
| |
| 21. Calyx hairy on inner surface; gypsum soils |
| L. arenicola |
| 21' Calyx not hairy on inner surface; generally not gypsum soils |
| |
| 22. Leaf not lobed; corolla tube without hairy pads where filaments attach |
| L. bigelovii |
| 22' Leaf lobed; corolla tube with hairy pads where filaments attach |
| L. dichotomus |
| 19' Corolla open in daytime; calyx membrane generally narrower than ribs (if wider, then corolla with red marks near throat) |
| |
| 23. Flowers generally sessile, corolla generally glabrous inside (if otherwise, leaves not lobed) (sect. Dianthoides) |
| |
| 24. Calyx lobes free to base, margins translucent; corolla tube very short |
| |
| 25. Stem long, thread-like, openly branched at base; calyx ribs with purple marks at base |
| L. bellus |
| 25' Stem not thread-like, compactly branched; calyx ribs without purple marks near base |
| |
| 26. Corolla bell-shaped, white with 2 red marks at base of lobes |
| L. demissus |
| 26' Corolla funnel-shaped, blue-purple or cream with purple kidney-shaped crest at base of lobes |
| L. parryae |
| 24' Calyx fused by membranes; corolla tube conspicuous |
| |
| 27. Leaves not lobed; tips of corolla lobes finely toothed |
| L. dianthiflorus |
| 27' Leaves deeply lobed; tips of corolla lobes entire |
| |
| 28. Calyx membrane much wider than ribs; San Gabriel Mountains |
| L. concinnus |
| 28' Calyx membrane as wide as ribs |
| |
| 29. Corolla 1015 mm, tube slightly exserted from calyx; San Bernardino Mountains |
| L. killipii |
| 29' Corolla 1525 mm, tube long-exserted from calyx; Peninsular Ranges |
| L. orcuttii |
| 23' Flowers generally on thread-like pedicels (if sessile, then corolla with hairy ring inside tube); leaf palmate, lobes very short (sect. Dactylophyllum) |
| |
| L. lemmonii |
| 30' Flowers on thread-like pedicels |
| |
| 31. Corolla tube and filaments glabrous; corolla generally < calyx |
| |
| 32. Stem generally branched above base or unbranched; corolla tube << lobes; stamens exserted; seeds 1 per chamber |
| L. harknessii |
| 32' Stem branched at base; corolla tube ± = lobes; stamens included; seeds > 1 per chamber |
| L. pygmaeus |
| 33. Corolla white; mainland |
| subsp. continentalis |
| 33' Corolla blue; Channel Islands |
| subsp. pygmaeus |
| 31' Corolla tube, filaments, or both hairy; corolla generally > calyx |
| |
| 34. Filaments generally hairy at base (if glabrous, then attached at hairy ring inside corolla) |
| |
| 35. Corolla 24 mm; hairy ring generally present inside corolla tube, tube = lobes |
| L. septentrionalis |
| 35' Corolla 415 mm; hairy ring 0 inside corolla tube, base of filaments hairy, tube << lobes |
| |
| 36. Stem diffusely branched at base; calyx lobes as wide as membrane; corolla veins obscure |
| L. filipes |
| 36' Stem branched above base; calyx lobes narrower than membrane; corolla veins conspicuous |
| L. liniflorus |
| 34' Filaments glabrous, attached above hairy ring |
| |
| 37. Corolla tube generally < lobes |
| L. aureus |
| 38. Corolla lobes bright yellow |
| subsp. aureus |
| subsp. decorus |
| 37' Corolla tube generally > lobes |
| |
| 39. Stigmas 24 mm; corolla throat widely widened, 3 mm; San Francisco Bay Area, South Coast Ranges |
| L. ambiguus |
| 39' Stigmas 1 mm; corolla throat not widened, < 2 mm; San Francisco Bay Area, North Coast Ranges |
| |
| 40. Corolla tube white, pink, or lilac, = calyx |
| L. bolanderi |
| 40' Corolla tube maroon, > 1.5 × calyx |
| L. rattanii
|