| |
| | 2. Ligules yellow; fruit smooth, outer pappus 0 |
| M. incana |
| | 2' Ligules white; fruit minutely spiny, outer pappus of irregular teeth |
| M. saxatilis |
| | 3. Upper leaves generally 1–2-pinnately lobed |
| |
| | 4. Stems densely leafy; upper leaves (ob)ovate, 2-pinnately divided into linear segments |
| var. implicata |
| | 4' Stems ± sparsely leafy; upper leaves linear to lanceolate, sharply and narrowly lobed |
| var. tenuifolia |
| | 3' Upper leaves generally entire |
| |
| | 5. Upper leaves generally linear to ovate, sometimes obtuse — coastal bluffs |
| var. saxatilis |
| | 5' Upper leaves lanceolate to elliptic, generally acute |
| |
| var. arachnoidea |
| | 6' Herbage glabrous to ± hairy |
| var. commutata |
| |
| | 7. Cauline leaves with ear-like basal lobes; involucre generally spheric; outer phyllaries round |
| M. coulteri |
| | 7' Cauline leaves generally without ear-like basal lobes; involucre bell-shaped; outer phyllaries lanceolate to ovate |
| |
| | 8. Outer ligules generally exserted 1–4 mm |
| |
| | 9. Stem generally leafy; outer pappus 0 |
| |
| | 10. Plants generally 10–30 cm, not mat-like; cauline leaves generally not fleshy, toothed or lobes narrow, sharp |
| M. foliosa |
| | 10' Plant generally 2–10 cm, mat-like; cauline leaves generally fleshy, lobes 1–3 pairs, short, wide, obtuse |
| M. indecora |
| | 9' Stem leaves generally much reduced upward; outer pappus present |
| |
| | 11. Basal leaves generally fleshy, lobes 3–8 pairs, wide, short, ± equal, generally toothed; outer pappus a scalloped crown, bristles 0 |
| M. phaeocarpa |
| | 11' Basal leaves generally not fleshy, toothed or narrowly lobed; outer pappus of needle-like teeth, bristle 1 |
| |
| | 12. Basal leaves generally (ob)lanceolate; corolla generally 4.5–6 mm, (pale) yellow; fruit generally 1.2–1.8 mm, veined to tip; pollen 3-pored |
| M. clevelandii |
| | 12' Basal leaves generally obovate; corolla generally 6–8 mm, white or pale yellow; fruit generally 1.8–2.3 mm, very tip veinless; pollen 4-pored |
| M. stebbinsii |
| | 8' Outer ligules exserted > 5 mm |
| |
| | 13. Stem scapose; leaves generally long-hairy at base |
| M. californica |
| | 13' Stems leafy, ± branched; basal leaves generally not long-hairy at base |
| |
| | 14. Cauline leaves generally narrowly triangular, with 5–10 pairs of narrow, sharp teeth or lobes; scarious margins of outer phyllaries > 0.6 mm |
| M. squalida |
| | 14' Cauline leaves generally lanceolate or (ob)ovate, entire or with short teeth or lobes; scarious margins of outer phyllaries < 0.5 mm |
| |
| | 15. Basal leaves generally not fleshy, narrowly toothed or lobed |
| |
| | 16. Corolla generally < 14 mm; outer ligules exserted < 8 mm; Channel Islands |
| M. foliosa |
| | 16' Corolla generally > 15 mm; outer ligules exserted > 9 mm; San Joaquin Valley, East of Sierra Nevada, Desert |
| M. glabrata |
| | 15' Basal leaves ± fleshy, with 3–8 pairs of ± equal, short, wide, generally toothed lobes |
| |
| | 17. Ligules generally white (yellow); fruit generally 1–2 mm; outer pappus 0; not of desert habitats |
| M. floccifera |
| | 17' Ligules medium yellow; fruit generally 2–4 mm; outer pappus present; desert habitats |
| |
| | 18. Cauline leaves widest at base; outer pappus a scalloped crown, bristles 0 |
| M. sonchoides |
| | 18' Cauline leaves generally narrowed to strap-like base; outer pappus of irregular teeth, bristles 0–6 |
| M. torreyi
|