Thelesperma megapotamicum |
Thelesperma filifolium |
|
---|---|---|
green threads, Hopi tea, Hopi tea greenthread, rayless greenthread |
Navajo tea, plains greenthread, stiff greenthread |
|
Habit | Perennials or subshrubs, (20–)30–80+ cm. | Annuals (sometimes persisting), 10–40(–70+) cm. |
Cauline leaves | ± scattered over proximal 1/2–3/4 of plant heights, internodes mostly 40–100 mm; lobes mostly linear to filiform, sometimes oblanceolate, 20–40(–50+) × 0.5–1(–2.5) mm. |
crowded to ± scattered over proximal 1/2–3/4 of plant heights, internodes mostly 10–35(–50+) mm; lobes mostly linear to filiform, sometimes oblanceolate, 5–30(–55+) × 0.5–1(–3+) mm. |
Ray florets | 0. |
8; laminae yellow to golden yellow (sometimes proximally suffused with red-brown), 12–20+ mm. |
Disc corollas | yellow, often with red-brown nerves, throats shorter than lobes. |
red-brown or yellow with red-brown nerves, throats shorter than lobes. |
Calyculi | of 3–5+ ovate to oblong bractlets 1–2(–3) mm. |
of 7–8+ linear to narrowly triangular bractlets (2–)4–8+ mm. |
Cypselae | 5–8 mm; pappi 1–2(–3) mm. |
3.5–4+ mm; pappi 0.5–1(–2+) mm. |
2n | = 22, 44. |
= 16, 18. |
Thelesperma megapotamicum |
Thelesperma filifolium |
|
Phenology | Flowering (Apr–)May–Oct. | Flowering Mar–Aug(–Oct). |
Habitat | Disturbed places on sands or clays, oak/juniper woodlands, desert scrub, yellow-pine forests | Disturbed sites on clays or sandy soils, rocky slopes, often on limestone |
Elevation | 300–2900 m (1000–9500 ft) | 10–2200 m (0–7200 ft) |
Distribution |
AR; AZ; CO; KS; NE; NM; OK; SD; TX; UT; WY; South America; Mexico (Chihuahua, Coahuila)
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AR; CO; KS; LA; MO; MS; NE; NM; OK; SD; TX; WY; Mexico (Nuevo León)
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Discussion | Thelesperma megapotamicum sometimes persists after plantings outside its natural range in the flora area and may become established (e.g., in California). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
As here circumscribed, Thelesperma filifolium includes plants that others have treated as a distinct species or variety: T. intermedium or T. filifolium var. intermedium, characterized as plants mostly 10–40 cm (versus taller); internodes “relatively short” (versus longer); calyculus bractlets mostly 1/4–1/2 lengths of phyllaries (versus more than 1/2 as long); ray corollas yellow (versus “golden yellow”); disc corollas yellow (versus sometimes red-brown); distribution mostly north and west of the typical form (Colorado, Kansas, Nebraska, New Mexico, w Oklahoma, South Dakota, c and w Texas, Wyoming). According to A. Cronquist (1980), Thelesperma trifidum (Poiret) Britton has been misapplied (e.g., M. L. Fernald 1950) to T. filifolium. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 202. | FNA vol. 21, p. 202. |
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma | Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma |
Sibling taxa | ||
Synonyms | Bidens megapotamica, T. gracile | Coreopsis filifolia, T. filifolium var. intermedium, T. intermedium |
Name authority | (Sprengel) Kuntze: Revis. Gen. Pl. 3(2): 182. (1898) | (Hooker) A. Gray: Hooker’s J. Bot. Kew Gard. Misc. 1: 252. (1849) |
Web links |