Perennials or subshrubs (in rock crevices). Involucres funnelform, campanulate, or hemispheric, 5–11 × 3.5–14 mm. Ray-florets 0, or 3–5, or 6–18; corollas yellow. Disc-florets 9–200; corollas yellow or white. Cypselae linear, linear-lanceolate, oblanceolate or oblong to oblanceolate, flattened, often obscurely rounded or angled on 1 or both surfaces, margins usually inconspicuously calloused and sparsely short-hairy; pappi 0 or of 1–2 (–6) equal or subequal, smooth, antrorsely barbellulate, or subplumose bristles 0.5–4.6 mm plus callous crowns or hyaline scales. x = 17.

Distribution

United States, Mexico

Discussion

Species 29 (22 in the flora).

Selected References

Powell, A. M. 1973b. Taxonomy of Perityle, section Laphamia (Compositae–Peritylanae). Sida 5: 61–128.

Lower Taxa

Perityle ajoensis, Perityle ambrosiifolia, Perityle angustifolia, Perityle bisetosa, Perityle cochisensis, Perityle congesta, Perityle dissecta, Perityle gilensis, Perityle gracilis, Perityle huecoensis, Perityle intricata, Perityle inyoensis, Perityle lemmonii, Perityle lindheimeri, Perityle megalocephala, Perityle saxicola, Perityle specuicola, Perityle stansburyi, Perityle staurophylla, Perityle tenella, Perityle villosa, Perityle warnockii

Key

1	Corollas white; rays 0; plants 2–12 cm; Texas (Big Bend area)	> 2
1	Corollas yellow; rays 0, or 3–5, or 6–18; plants (4–)12–75 cm; Arizona, California, Nevada, New Mexico, Texas, or Utah	> 3
2	Pappi 0 or callous crowns (bristles 0); plants densely scabrous-pubescent	Perityle warnockii
2	Pappi usually of 2–3(–5) bristles; plants glabrate, minutely hairy, or scabrous-hispidulous	Perityle bisetosa
3	Rays 3–5 or 6–18	> 4
3	Rays usually 0 (sometimes 1–2, reduced, in P. ambrosiifolia)	> 9
4	Leaf blades broadly ovate, ovate-deltate, ovate-lanceolate, or ovate-rhombic; disc florets 11–22; Texas	> 5
4	Leaf blades ± cruciform, subdeltate, or subovate, usually 3-partite or lobed, divided, or pinnate; disc florets 30–200; Arizona, Nevada, New Mexico, Utah	> 6
5	Disc florets 11–13; Hueco Mountains	Perityle huecoensis
5	Disc florets 16–22; Edwards Plateau	Perityle lindheimeri
6	Leaf blades usually ± cruciform, sometimes lobed or pinnate; New Mexico	Perityle staurophylla
6	Leaf blades subdeltate, suborbiculate, or subovate, or deeply lobed, 3-foliolate, or 2–3-pinnate; Arizona, Nevada, Utah	> 7
7	Disc florets 60–80; leaf blades subdeltate, suborbiculate, or subovate, margins serrate or ± lobed; Nevada, Utah	Perityle stansburyi
7	Disc florets 75–200; leaf blades 3-foliolate, or 2–3-pinnate; Arizona	> 8
8	Leaf blades 2–3-pinnate (lobes linear to flat-filiform, scarcely broad- ened distally)	Perityle saxicola
8	Leaf blades usually 3-foliolate (lobes much broadened distally)	Perityle gilensis
9	Plants long-hairy, pilose, or villous	> 10
9	Plants glabrous, or hirtellous, hispidulous, or puberulent, or short-hairy, or short-tomentose	> 15
10	Leaf blades deeply dissected (lobes relatively numerous, irregular)	> 11
10	Leaf blades entire, serrate, or shallow-lobed	> 13
11	Phyllaries 4–6.4(–8) mm (apices acute); disc corolla throats broadly tubu-lar to subfunnelform; pappus bristles delicate	Perityle lemmonii
11	Phyllaries 6–9 or (5–)7–13 mm (apices usually attenuate, sometimes acute); disc corolla throats narrowly tubular to narrowly funnelform; pappus bristles moderately stout	> 12
12	Leaf blades 15–30 mm wide; phyllaries 14–20; Arizona	Perityle ambrosiifolia
12	Leaf blades 4–15 mm wide; phyllaries 12–15; Texas	Perityle dissecta
13	Leaf margins entire or with 1–3 lobes per side (leaves all alternate)	Perityle villosa
13	Leaf margins serrate (leaves opposite or alternate)	> 14
14	Pappi usually callous crowns (bristles 0); California	Perityle inyoensis
14	Pappus usually of single, delicate bristles 1–3 mm; Arizona, New Mexico	Perityle lemmonii
15	Plants densely short-hairy or short-tomentose	> 16
15	Plants glabrous, or hirtellous, hispidulous, or puberulent	> 17
16	Leaf margins serrate; plants densely short-hairy; nw Arizona, Nevada, Utah	Perityle tenella
16	Leaf margins usually shallow-crenate; plants densely short-tomentose; sw Arizona	Perityle ajoensis
17	Leaf blades 2–8(–15) mm (stems sparsely leafy)	> 18
17	Leaf blades 3–30 mm (stems moderately to densely leafy)	> 20
18	Pappus bristles usually 1–3(–4), rarely 0; se Utah	Perityle specuicola
18	Pappus bristles usually 0, sometimes 1–2; California, s Nevada	> 19
19	Heads borne singly or (2–3) in loose, corymbiform arrays; peduncles 10–45(–80) mm; leaf blades usually elliptic, lanceolate, lance-ovate, ovate, or suborbiculate (sometimes linear in var. oligophylla)	Perityle megalocephala
19	Heads (2–6) in tight, corymbiform arrays; peduncles 1–10 mm; leaf blades linear	Perityle intricata
20	Pappi usually 0, sometimes 1–2 bristles; plants glabrate or puberulent; Texas	Perityle angustifolia
20	Pappi usually of 1–3(–6) bristles, sometimes 0; plants glabrous, hirtellous, or short-hairy; Arizona, Nevada	> 21
21	Leaf blades usually deeply divided (lobes 3, relatively broad to linear, usually secondarily lobed, cleft, or parted, often ± cruciform, sometimes almost entire); sc Arizona	Perityle staurophylla
21	Leaf blades entire, toothed, or lobed; Arizona, Nevada	> 22
22	Plants 4–12(–15+) cm; petioles 5–30 mm (equal to or longer than blades; leaves usually glabrous); se Arizona	Perityle cochisensis
22	Plants 10–30(–45) cm (petioles shorter than blades; leaves hairy); nw Arizona, se Nevada	> 23
23	Leaf blades usually 3-lobed to ± cruciform; nw Arizona, se Nevada	Perityle gracilis
23	Leaf blades elliptic, lanceolate, or ovate, usually entire or 2–6-toothed; nw Arizona	Perityle congesta