Pectis longipes |
Pectis glaucescens |
|
---|---|---|
longstalk chinchweed, longstalk cinchweed, mat cinchweed |
sand dune chinchweed |
|
Habit | Perennials, 8–25 cm (rhizomes branched, 1–10 mm diam.); herbage lemon-scented or spicy-scented. | Annuals or perennials, 2–50 cm (across or high); herbage spicy-scented. |
Stems | ascending to erect (very leafy), glabrous. |
prostrate to erect, usually sparsely to densely puberulent (sometimes in decurrent lines), sometimes glabrate. |
Leaves | linear to linear-oblanceolate, 10–55 × 1–3 mm, margins with 1–4 pairs of setae, faces glabrous (conspicuously dotted on margins with round oil-glands 0.3–0.5 mm). |
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). |
Peduncles | (30–)50–160 mm. |
filiform, (3–)7–35(–54) mm. |
Involucres | campanulate. |
cylindric. |
Ray florets | (8–)13(–15); corollas 8–12 mm. |
5; corollas 3.5–5 mm. |
Disc florets | 25–50; corollas 4–6 mm (2-lipped). |
3–7; corollas 2–3 mm (2-lipped). |
Phyllaries | distinct, linear, linear-oblanceolate, or linear-elliptic, 5–8 × 0.7–2 mm (dotted with 1–3, swollen, subterminal oil-glands 0.3–0.4 mm plus 1–3 pairs of narrow, submarginal oil-glands). |
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). |
Heads | borne singly. |
borne singly or in diffuse, cymiform arrays. |
Cypselae | 2.5–4.5 mm, strigillose (hairs tips acute or blunt); ray pappi of 1–2 awns 3–3.5 mm; disc pappi of 2–30 unequal bristles 3–5 mm. |
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. |
2n | = 24, 48. |
= 48. |
Pectis longipes |
Pectis glaucescens |
|
Phenology | Flowering Apr–Nov. | Flowering year round. |
Habitat | Grasslands, oak-juniper-mesquite woodlands | Sandy or gravelly soils, grassy areas, openings in pinelands, scrub, roadsides |
Elevation | 900–1700 m (3000–5600 ft) | 0–50 m (0–200 ft) |
Distribution |
AZ; NM; Mexico (Chihuahua, Durango, Sonora)
|
FL; West Indies (Bahamas, Hispaniola, Jamaica) |
Discussion | Pectis longipes has been listed from Texas in floras; I have seen no collections from that state. Pectis longipes comprises two cytological races. Diploid, spicy-scented plants occur throughout the range. In southern Arizona, the diploid race is broadly sympatric but locally allopatric with a tetraploid, lemon-scented race. The tetraploid race is nested within the range of the diploids. The races are easily separable by odor, and although they are very similar morphologically, they can be separated also by statistically significant differences in floral dimensions and pollen size (M. A. Luckow 1983). Based upon those minute differences, the type collection is diploid. Because the races are so similar morphologically and because so many of the specimens of P. longipes in herbaria bear no indication of odor, I chose not to give the cytological races formal recognition. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 21, p. 226. | FNA vol. 21, p. 225. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Chthonia glaucescens, P. leptocephala, P. lessingii | |
Name authority | A. Gray: Smithsonian Contr. Knowl. 5(6): 69. (1853) | (Cassini) D. J. Keil: Sida 11: 386. (1986) |
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