Perityle gracilis (M. E. Jones) Rydb.

Perityle gracilis is known from southeastern Nevada in Meadow Valley Wash and in the Sheep Range. The only Arizona collection is the type (M. E. Jones in 1894, Kaibab Plateau). The 3-fid leaves with cuneate bases set P. gracilis apart from the similar P. congesta and P. tenella.

Perennials or subshrubs, 10–20(–25) cm (stems erect, spreading, or pendent); glabrate or densely puberulent. Leaves: petioles 2–5(–10) mm; blades palmately 3-lobed, or ± cruciform, sometimes entire, or with 1–3 lobes or teeth per side, 3–10(–15) × 2–15 mm, ultimate margins sometimes irregularly lobed or toothed. Heads borne singly or (2–6+) in corymbiform arrays, 5–7 × 4–5.5 mm. Peduncles 5–15 mm. Involucres campanulate. Phyllaries (8–)12–17, linear-lanceolate to lanceolate, 3.5–5.5 × 0.7–1.2 mm. Ray florets 0. Disc florets 30–42; corollas yellow, tubes 0.8–1.1 mm, throats ± tubular, (1.3–)1.6–2 mm, lobes 0.4–0.6 mm. Cypselae oblong-elliptic, 1.8–2.5(–2.8) mm, margins thin-calloused, short-hairy; pappi 0 or of 1(–3) stout bristles to 2 mm, usually plus callous crowns or vestigial, hyaline scales. 2n = 68.

Laphamia gracilis M. E. Jones, Proc. Calif. Acad. Sci., ser. 2, 5: 703. 1895

Monothrix fastigiata (Brand.) Rydberg
Laphamia fastigiata Brand. Bot. Gaz. 15; 451. 1899.
A suffruticose perennial with cespitose woody caudex; stems several, about 1 dm. high,
scabrous-puberulent ; lower leaves opposite, spatulate, petioled; stem-leaves rhombic-
spatulate, 1-2 cm. long, trifid, or the upper smaller and entire; heads solitary at the ends
of the stems, short-peduncled, discoid; involucre campanulate, 3-4 mm. high and nearly as
broad; bracts about 15, linear, acute, hispidulous-puberulent; disk-flowers 30-40; corollas
light-yellow, the tube puberulent; achenes 2 mm. long, slightly ciliate on the margins; awn
solitary or sometimes wanting.
Type locality: Sheep Mountain, Nevada. Distribution: Kjiown only from the type locality.

Perityle gracilis (M. E. Jones) Rydberg
Laphamia gracilis M. E. Jones, Proc. Calif. Acad. II. 5: 703. 1895.
A suffruticose perennial; stems decumbent or pendent from overhanging rocks, 2-3 dm. long, grayish-puberulent; leaves alternate; petioles 1-2 cm. long; blades 1.5-3 cm. long, broadly ovate in outline, pedately dissected, with the divisions again cleft into oblong or oblanceolate mostly obtuse lobes, puberulent and impressed-punctate; peduncles 3-5 cm. long; involucre turbinate, about 5 mm. high and 8 mm. broad; bracts puberulent, oblanceolate, short-acuminate; ray-flowers 10-12; ligules light-yellow, oblong, 7-8 mm. long, rather deeply 3-toothed; disk-corollas 2.5 mm. long, the tube about equaling the throat; achenes linear-oblong, 2 mm. long, sparingly ciliate on the slightly callous margin; pappus of a crown of short squamellae and 2 scabrous awns about as long as the achenes.
Type locality: Below Nagle's Ranch, Buckskin Mountains, Arizona. Distribution: Arizona.

Perityle gracilis là một loài thực vật có hoa trong họ Cúc. Loài này được (M.E.Jones) Rydb. mô tả khoa học đầu tiên năm 1914.