Perityle congesta (M. E. Jones) Shinners

The leaf blades of Perityle congesta usually have a tooth on each margin, cuneate bases, and unobtrusive veins abaxially; those of P. tenella usually have serrate margins, truncate bases, and raised veins abaxially. Perityle congesta is found on both rims and extending into the Grand Canyon and northward almost to the Utah border. Available specimens suggest that P. congesta and P. tenella intergrade where their ranges overlap in northwestern Arizona on the Colorado Plateau. Specimens from the Colorado Plateau have intermediate leaf shapes and induments.

Perennials or subshrubs, 10–30(–45) cm (densely clumped, stems spreading or pendent); hirtellous. Leaves: petioles 2.5–10(–15) mm (shorter than blades); blades elliptic, lanceolate, or ovate, 5–17(–20) × 4–8(–10) mm, (bases cuneate) margins usually entire or with 2(–6) teeth. Heads borne singly or (2–8) in corymbiform arrays, 5–6(–6.5) × 3.5–4.5(–5) mm. Peduncles 3–17 mm. Involucres campanulate. Phyllaries 12–16, narrowly lanceolate, oblong-lanceolate, or lanceolate, 3.2–4.5 × 0.8–1.4 mm. Ray florets 0. Disc florets 30–40; corollas yellow, tubes 0.8–1 mm, throats tubular to subfunnelform, 1.2–1.5 mm, lobes 0.3–0.5 mm. Cypselae narrowly oblanceolate, (2–)2.5–3 mm,margins thin-calloused, short-hairy; pappi of 1–2 subequal or unequal bristles 2–2.7 mm. 2n = 32.

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

Monothrix congesta (M. E. Jones) Rydberg
Laphamia congesta M. E. Jones, Proc. Calif. Acad. II. 5: 703. 1895.
A suffruticose perennial, with a woody caudex; stems numerous, 1-2 dm. high, grayish-
hispidulous, striate; leaves alternate; petioles about 2-5 mm. long; blades broadly lanceolate to
broadly ovate or rhombic-ovate, 3-12 mm. long, sinuately toothed, scabrous-hispidulous; heads
solitary at the ends of the branches, 15-20-flowered; involucre campanulate, 4-5 mm. high
and 5-6 mm. broad, scabrous-puberulent; bracts linear-oblong, about 12, acute; rays none;
disk-corollas 2.5-3 mm. long, cr:;am-colored; tube about equaling the throat; achenes oblong,
very scabrous-puberulent; awn solitary, equaling the achene.
Type locality: Mesa below Buckskin Mountains, Arizona. Distribution: Arizona.

Perityle congesta là một loài thực vật có hoa trong họ Cúc. Loài này được (M.E.Jones) Shinners mô tả khoa học đầu tiên năm 1959.