Pectis glaucescens |
Pectis rusbyi |
|
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sand dune chinchweed |
Rusby's chinchweed, Rusby's cinchweed |
|
Habit | Annuals or perennials, 2–50 cm (across or high); herbage spicy-scented. | Annuals, 5–50 cm (taprooted); herbage spicy-scented. |
Stems | prostrate to erect, usually sparsely to densely puberulent (sometimes in decurrent lines), sometimes glabrate. |
erect or ascending, glabrous or sparsely puberulent (in decurrent lines). |
Leaves | narrowly linear, 10–35 × 0.2–1.8 mm, margins with 1–5 pairs of setae 1–2 mm, faces glabrous (abaxial submarginally dotted with broadly elliptic to circular oil-glands 0.2–0.3 mm, sometimes with additional, scattered oil-glands). |
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). |
Peduncles | filiform, (3–)7–35(–54) mm. |
20–80 mm. |
Involucres | cylindric. |
campanulate. |
Ray florets | 5; corollas 3.5–5 mm. |
8(–13); corollas 5–11 mm. |
Disc florets | 3–7; corollas 2–3 mm (2-lipped). |
(7–)20–55; corollas 3.5–5 mm (2-lipped). |
Phyllaries | distinct, linear-oblanceolate, 4–5 × 0.8–1 mm (dotted with 1–2 elliptic, subapical oil-glands 0.2–0.3 mm, sometimes with additional, smaller submarginal or scattered oil-glands). |
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). |
Heads | borne singly or in diffuse, cymiform arrays. |
borne singly or in open, cymiform arrays. |
Cypselae | 2.5–3 mm, strigillose; pappi of 0–5, antrorsely scabrid bristles or slender scales 1–2 mm plus 0–5 entire or irregularly lacerate scales 0.2–0.7 mm. |
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 | = 48. |
= 24 (as P. palmeri). |
Pectis glaucescens |
Pectis rusbyi |
|
Phenology | Flowering year round. | Flowering Jul–Oct. |
Habitat | Sandy or gravelly soils, grassy areas, openings in pinelands, scrub, roadsides | Deserts, desert grasslands, arid scrub, dry woodlands |
Elevation | 0–50 m (0–200 ft) | 600–1600 m (2000–5200 ft) |
Distribution |
FL; West Indies (Bahamas, Hispaniola, Jamaica) |
AZ; Mexico (Baja California Sur, Sinaloa, Sonora)
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Discussion | Pectis glaucescens is widespread in southern Florida and the Bahamas. Human disturbances, especially road constructions, have created habitats suitable for it. It grows most commonly on limestone soils in open, grassy sites. Occasionally, it is a lawn weed. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Pectis rusbyi is much less common in Arizona than P. papposa var. papposa, with which it sometimes grows. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 225. | FNA vol. 21, p. 227. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Chthonia glaucescens, P. leptocephala, P. lessingii | P. palmeri |
Name authority | (Cassini) D. J. Keil: Sida 11: 386. (1986) | Greene ex A. Gray: in A. Gray et al., Syn. Fl. N. Amer. 1(2): 361. (1884) |
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