Rusby's Chinchweed

Pectis rusbyi is much less common in Arizona than P. papposa var. papposa, with which it sometimes grows.

Annuals, 5–50 cm (taprooted); herbage spicy-scented. Stems erect or ascending, glabrous or sparsely puberulent (in decurrent lines). Leaves linear to narrowly elliptic, 10–50 × 1–5 mm, margins with 1–3 pairs of setae, faces glabrous or sparsely puberulent (dotted on margins with round oil-glands 0.2–0.7 mm). Heads borne singly or in open, cymiform arrays. Peduncles 20–80 mm. Involucres campanulate. Phyllaries distinct, oblong or narrowly obovate, 4–7 × 1–2 mm (dotted with 0–2, subterminal oil-glands plus 2–4 pairs of inconspicuous, round to narrowly elliptic, submarginal oil-glands). Ray florets 8(–13); corollas 5–11 mm. Disc florets (7–)20–55; corollas 3.5–5 mm (2-lipped). Cypselae 3–4.5 mm, strigillose or short-pilose; ray pappi of 1–4, antrorsely barbed awns 1–4 mm or coroniform; disc pappi of 15–30, antrorsely barbed bristles 2.5–5 mm or coroniform. 2n = 24 (as P. palmeri).

Pectis palmeri S. Watson

Pectis rusbyi Greene; A. Gray, Syn. Fl. V: 361. 1884 A low annual; stem rather simple, about 1 dm. high, angled, glabrous; leaves flat, linear or linear-oblanceolate, mostly obtuse, 2-3.5 cm. long, 1-3 mm. wide, with 2-3 pairs of basal bristles; peduncles 3-6 cm. long; involucre 4-5 mm. high and as wide, turbinate; bracts about 8, flat, slightly keeled at the base, obtuse, with a conspicuous apical gland; ray-flowers about 8; ligules yellow, 6 mm. long, 2 mm. wide; disk-flowers 20-30; corollas 4 mm. long; achenes 4 mm„ long, sparingly hirsutulous or glabrate; pappus of the disk-flowers of many minute awntipped squameUae; that of the ray-flowers of 2 or 3 slender awns, 2.5-3 mm. long.
Type locality: Beaver Creek, Arizona. Distribution: Known only from the type locality.

Pectis rusbyi, or Rusby's cinchweed, is a summer blooming annual plant in the genus Pectis. Its floral region is Arizona.