1	"Perennial herb (biennial) or subshrub, rarely flowering 1st year; inner fruit pappus generally of 10--20 scales in 3--4 +- equal series; leaf blade gland-pitted under hairs; heads discoid (sect. <i>Macrocarphus</i>)"	2
1	"Annual; inner fruit pappus 0, crown-like, or of 4(5) or (7)8 scales in 1 or 2 unequal series, outer << inner; leaf blades (except <i>Chaenactis macrantha</i>) not gland-pitted; heads discoid or radiant"	9
2	"Leaves generally cauline (also basal in <i>Chaenactis douglasii</i>); heads not scapose, (1)2--25+ per stem; plants not or scarcely cespitose or matted"	3
2	"Leaves +- basal; heads +- scapose, 1(3) per stem; plants cespitose to +- matted"	5
3	"Perennial herb or biennial, rarely flowering 1st year or slightly woody; proximal hairs cobwebby to tomentose, +- gray, thinning with age; basal leaves generally persistent, largest leaf blades +- elliptic, not flat"	"Chaenactis douglasii var. douglasii"
3	"Generally subshrub; proximal hairs (especially stems) +- felty, +- white, persistent; basal leaves generally 0, largest leaf blades +- deltate, +- flat"	4
4	"Longest phyllaries 10--13 mm, outer +- tomentose, not or scarcely glandular; e PR"	"Chaenactis parishii"
4	"Longest phyllaries 14--18 mm, outer generally glandular-hairy, other hairs 0 or scarce; e KR, n CaRH"	"Chaenactis suffrutescens"
5	"Outer phyllaries silky-tomentose, nonglandular"	"Chaenactis alpigena"
5	"Outer phyllaries generally glandular-hairy, often also cobwebby to woolly or shaggy-hairy"	6
6	"Largest leaf blades +- deltate to ovate, +- flat; 1&deg; lobes generally 2--4(5) pairs, tips +- flat"	7
6	"Largest leaf blades +- elliptic or cylindric to +- fusiform, not flat; 1&deg; lobes (4)5--18+ pairs, tips curled and/or twisted"	8
7	"Plant 2--10(12) cm; leaves 2.5--5 cm; longest phyllaries 9--12(14) mm; corolla 5.5--8 mm; longest pappus scales 3--5 mm"	"Chaenactis nevadensis"
7	"Plant (10)25--45(60) cm; leaves 5--10 cm; longest phyllaries 14--18 mm; corolla 8.5--10 mm; longest pappus scales 7--9 mm"	"Chaenactis suffrutescens"
8	"Largest leaf blades +- elliptic; 1&deg; lobes (4)5--9(12) pairs, not or scarcely overlapping"	"Chaenactis douglasii var. alpina"
8	"Largest leaf blades cylindric to +- fusiform; 1&deg; lobes (7)10--18+ pairs, +- overlapping"	"Chaenactis santolinoides"
9	"Proximal hairs mealy, scaly, or powdery; largest leaf blades generally +- deltate, (2)3--4-pinnately lobed (sect. <i>Acarphaea</i>)"	10
9	"Proximal hairs cobwebby to woolly or 0; largest leaf blades linear, entire, or +- elliptic (to ovate), 1--2-pinnately lobed (sect. <i>Chaenactis</i>)"	12
10	"Phyllary tips acute or scarcely acuminate, +- flat, +- green; leaf lobe tips +- flat; receptacle epaleate; fruit compressed; pappus 0 or longest scales <= 0.5 mm"	"Chaenactis artemisiifolia"
10	"All or inner phyllary tips long-acuminate, needle-like, +- red; leaf lobe tips +- cylindric; receptacle paleate; fruit not compressed; longest inner fruit pappus scales generally 3--5 mm"	11
11	"Leaves basal and cauline, longest 1--6(7) cm; petiole slender, flexible, base scarcely enlarged"	"Chaenactis carphoclinia var. carphoclinia"
11	"Leaves generally basal, longest 7--10 cm; petiole thick, stiff, base strongly enlarged"	"Chaenactis carphoclinia var. peirsonii"
12	"Corolla white to +- pink or rarely pale yellow; generally in or near GB, D"	13
12	"Corolla bright to dark yellow; generally CA-FP"	17
13	"Heads radiant; peduncle distally generally glandular-hairy, or +- glabrous in fruit; outer corollas bilateral, spreading, > inner; inner fruit pappus generally of 4 scales in 1 series"	14
13	"Heads discoid; peduncle nonglandular; outer corollas radial, spreading or not, +- = inner; pappus of (6)8 scales in 2 unequal series, outer << inner"	15
14	"Longest pappus 6--8.5 mm, exceeding corolla, tips visible among buds; proximal hairs 0 by flowering time; largest leaf blades entire or 1-pinnately lobed, lobes generally 1--2(5) pairs; outer phyllaries +- glabrous in fruit, tip acute"	"Chaenactis fremontii"
14	"Longest pappus 1.5--6 mm, not exceeding corolla, tips hidden; proximal hairs persisting at least at nodes by flowering time; largest leaf blades generally 1--2-pinnately lobed, 1&deg; lobes 4--8 pairs; outer phyllaries glandular-hairy and/or +- cobwebby in fruit, tip +- obtuse"	"Chaenactis stevioides"
15	"Corolla open at night, anthers +- included; inner corollas 9--12(15) mm, 1.8--2.2 &times; fruit; leaf blades +- gland-pitted under hairs"	"Chaenactis macrantha"
15	"Corolla open during day, anthers exserted; inner corolla 4--10 mm, +- = fruit; leaf blades not gland-pitted"	16
16	"Longest phyllaries 10--18 mm, outer nonglandular, glabrous proximally, densely puberulent distally, tip generally recurved, flexible; pappus scales 8"	"Chaenactis xantiana"
16	"Longest phyllaries 4.5--10(12) mm, outer generally glandular-hairy, hairs otherwise various, uniform, tip erect, stiff; pappus scales generally < 8"	"{hybrids; see Jepson genus note}"
17	"Inner fruit pappus generally of 7--8 scales in 2 series, outer << inner"	"Chaenactis glabriuscula var. heterocarpha"
17	"Inner fruit pappus generally of 4 scales in 1 series"	18
18	"Proximal hairs tomentose to woolly, +- white; leaves +- basal, persistent"	"Chaenactis glabriuscula var. lanosa"
18	"Proximal hairs 0 or +- cobwebby, +- gray; leaves basal (withering) and cauline"	19
19	"Largest leaf blades generally 2-pinnately lobed, fleshy; stem +- spreading; SCo, coastal dunes, bluffs"	"Chaenactis glabriuscula var. orcuttiana"
19	"Largest leaf blades 1(2)-pinnately lobed, scarcely fleshy; stem erect to ascending; inland from coast"	20
20	"Longest phyllaries 5--7 mm, 1--2 mm wide, outer +- silky-cobwebby at least medially in fruit, often also +- glandular-hairy; longest pappus 2--4 mm, 0.4--0.7 &times; corolla"	"Chaenactis glabriuscula var. glabriuscula"
20	"Longest phyllaries 7--9 mm, 2--3 mm wide, outer becoming glabrous in fruit; longest pappus generally 5--8 mm, +- 0.9(1) &times; corolla"	"Chaenactis glabriuscula var. megacephala"