Pectis longipes |
Pectis linearifolia |
|
---|---|---|
longstalk chinchweed, longstalk cinchweed, mat cinchweed |
Florida chinchweed, Florida cinchweed |
|
Habit | Perennials, 8–25 cm (rhizomes branched, 1–10 mm diam.); herbage lemon-scented or spicy-scented. | Annuals, 4–40 cm; herbage lemon-scented. |
Stems | ascending to erect (very leafy), glabrous. |
decumbent to erect (very leafy), glabrous or puberulent (in decurrent lines). |
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). |
linear, 10–50 × 1–3 mm, margins with 2–6 pairs of setae, faces glabrous (abaxial dotted submarginally with round oil-glands 0.2–0.5 mm). |
Peduncles | (30–)50–160 mm. |
0–1 mm. |
Involucres | campanulate. |
narrowly campanulate to cylindric. |
Ray florets | (8–)13(–15); corollas 8–12 mm. |
5; corollas 4.5–5.5 mm. |
Disc florets | 25–50; corollas 4–6 mm (2-lipped). |
4–10; corollas 2.5–3 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 or linear-oblanceolate, 5–6 × 1–1.5 mm (dotted with scattered, elliptic oil-glands 0.4–0.5 mm). |
Heads | borne singly. |
borne singly or in congested, (leafy) 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. |
2.25–3.25 mm, puberulent; pappi (ray and disc similar) of 2–5 antrorsely barbed bristles or awns 1.5–2.5 mm plus shorter, barbellate scales. |
2n | = 24, 48. |
= 48. |
Pectis longipes |
Pectis linearifolia |
|
Phenology | Flowering Apr–Nov. | Flowering mostly Aug–Dec. |
Habitat | Grasslands, oak-juniper-mesquite woodlands | Open sites, sandy-gravelly soils with grasses and other herbs |
Elevation | 900–1700 m (3000–5600 ft) | 0–50 m (0–200 ft) |
Distribution |
AZ; NM; Mexico (Chihuahua, Durango, Sonora)
|
FL
|
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.) |
Reports of Pectis linearifolia from Jamaica were based on misidentifications of diminutive, short-peduncled individuals of P. glaucescens (D. J. Keil 1986). In Florida, P. linearifolia and P. glaucescens are largely allopatric; they occasionally occur in mixed populations. No hybrids are known. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 226. | FNA vol. 21, p. 226. |
Parent taxa | ||
Sibling taxa | ||
Name authority | A. Gray: Smithsonian Contr. Knowl. 5(6): 69. (1853) | Urban: Symb. Antill. 5: 276. (1907) |
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