Lemmon’s rock daisy

Laphamia lemmonii A. Gray, Proc. Amer. Acad. Arts 16: 101. 1880 (as lemmoni); L. dissecta Torrey subsp. lemmonii (A. Gray) W. E. Niles

Perennials or subshrubs, 6–17(–23) cm (densely clumped, stems leafy); usually densely pilose to villous, sometimes glabrate. Leaves (opposite or alternate): petioles 3–8(–10) mm (usually shorter than blades); blades ovate to ovate-deltate (margins crenate, lacerate, laciniate, or serrate), or 3–5-lobed or pinnately divided (lobes crenate, lacerate, laciniate, lobed, or serrate), 6–18 × 7–20 mm. Heads borne singly or (2–3) in corymbiform arrays (often obscured by leaves), 7–10 × 5–9 mm. Peduncles 1–5(–10) mm. Involucres campanulate. Phyllaries 10–16, linear-lanceolate, lanceolate, to oblanceolate, 4–6.4(–8) × 1–1.7 mm (apices acute). Ray florets 0. Disc florets 20–40; corollas yellow, often tinged with purple, tubes 1–1.9 mm, throats broadly tubular to subfunnelform, 2–2.5(–2.9) mm, lobes 0.4–0.6 mm. Cypselae narrowly oblong to narrowly oblanceolate, 2.5–3.2(–3.6) mm, margins thin-calloused, short-hairy; pappi usually of 1(–2) delicate bristles 1–3(–4) mm, rarely plus vestigial, hyaline scales, sometimes 0. 2n = 34.

Flowering spring–fall. Crevices of granitic boulders and cliffs; 600–2300 m; Ariz., N.Mex.; Mexico (Chihuahua).

Perityle lemmonii, which occurs in the mountain areas of southeastern Arizona and southwestern New Mexico, has variable leaf morphology that is often consistent within geographic populations. Its former inclusion within P. dissecta is discussed under that species.