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green threads, Hopi tea, Hopi tea greenthread, rayless greenthread

hairy greenthread, Navajo tea

greenthread

Habit Perennials or subshrubs, (20–)30–80+ cm. Perennials, 10–30(–40+) cm (caudices often woody). Annuals, perennials, or subshrubs, 10–70+ cm.
Stems

usually 1, erect, branched distally or ± throughout.

Leaves

mostly basal, basal and cauline, or mostly cauline; mostly opposite (distal rarely alternate);

blades usually 1(–3)-pinnately lobed (ultimate lobes oblanceolate to filiform), faces usually glabrous, rarely hairy.

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.

mostly crowded over proximal 1/4(–1/2) of plant heights, internodes mostly 1–5(–35 mm);

lobes mostly oblanceolate to linear, (5–)10–35(–45+) × (1–)2–3(–5) mm.

Heads

radiate or discoid, borne singly or in loose, corymbiform arrays.

Involucres

hemispheric to urceolate, 4–15+ mm diam.

Receptacles

flat to convex, paleate;

paleae falling, (whitish with red-brown striae, each ± appressed to abaxial face of subtended cypsela), obovate to oblong, scarious.

Ray florets

0.

0, or 8;

laminae yellow, (6–)12–20+ mm.

0 or ca. 8, neuter;

corollas yellow or red-brown, or bicolored (yellow and red-brown).

Disc florets

20–100+, bisexual, fertile;

corollas yellow (with red-brown nerves) or red-brown, either with throats equal to or longer than 5, ± deltate, ± equal lobes, or with throats shorter than 5, ± lance-linear, ± unequal lobes (in either form, the abaxial sinus usually ± deeper than others).

Disc corollas

yellow, often with red-brown nerves, throats shorter than lobes.

yellow, sometimes with red-brown nerves, throats equal to or longer than lobes.

Phyllaries

5–8 in ± 2 series, persistent, connate 1/5–7/8+ their lengths, lance-ovate to ovate, ± equal, ± leathery to membranous, margins (of distinct apices) scarious.

Calyculi

of 3–5+ ovate to oblong bractlets 1–2(–3) mm.

of 7–9 deltate to lance-linear bractlets 2–4+ mm.

of 3–8+ distinct, usually spreading or reflexed, usually linear to subulate, herbaceous bractlets.

Cypselae

5–8 mm;

pappi 1–2(–3) mm.

5–7 mm;

pappi usually 0, rarely 0.1–0.5 mm.

(dark red-brown or stramineous) outer often arcuate, shorter, inner more columnar, usually some or all ± obcompressed (each usually shed together with its subtending palea), faces smooth or papillate to tuberculate or verrucate, margins sometimes ± winged;

pappi 0, or persistent, of 2 retrorsely ciliate, subulate scales or awns.

x

= 12.

2n

= 22, 44.

= 22, 24.

Thelesperma megapotamicum

Thelesperma subnudum

Thelesperma

Phenology Flowering (Apr–)May–Oct. Flowering May–Sep.
Habitat Disturbed places on sands or clays, oak/juniper woodlands, desert scrub, yellow-pine forests Openings in pinyon/juniper or yellow-pine forests, often on talus or "balds"
Elevation 300–2900 m [1000–9500 ft] 1000–2900 m [3300–9500 ft]
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 subnudum includes plants that have been treated as distinct species and/or varieties (some of which have been treated as of conservation concern). See C. J. Hansen et al. (2002) for an alternate interpretation of T. subnudum.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Species 10+ (9 in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Distribution
from FNA
AR; AZ; CO; KS; NE; NM; OK; SD; TX; UT; WY; South America; Mexico (Chihuahua, Coahuila)
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; MT; ND; NM; NV; UT; WY; AB
[WildflowerSearch map]
[BONAP county map]
from USDA
w North America; Mexico; South America
[BONAP county map]
Parent taxa Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma Asteraceae > tribe Heliantheae > subtribe Coreopsidinae
Sibling taxa
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. nuecense, T. simplicifolium, T. subnudum
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. megapotamicum, T. nuecense, T. simplicifolium
Subordinate taxa
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. megapotamicum, T. nuecense, T. simplicifolium, T. subnudum
Key
1.Throats of disc corollas equal to or longer than lobes; pappi usually 0, rarely of 2 awns 0.1–0.3(–0.5) mm→ 2
1.Throats of disc corollas shorter than lobes; pappi usually of 2 awns or scales (0.5–)1–3 mm, rarely 0→ 4
2.Cauline leaves ± scattered over proximal 3/4+ of plant heights, internodes mostly 45–95 mmT. simplicifolium
2.Cauline leaves ± crowded over proximal 1/4–1/2 of plant heights, internodes mostly 5–25+ mm or 1–5(–35) mm→ 3
3.Leaf lobes mostly linear to filiform, 5–25(–45+) × 0.5(–1) mm; cypselae 2–3 mmT. longipes
3.Leaf lobes mostly oblanceolate to linear, (5–)10–35(–45+) × (1–)2–3(–5) mm; cypselae 5–7 mmT. subnudum
4.Perennials (sometimes flowering first year); calyculi of 3–5+, ovate to oblong bractlets 1–3 mm; ray florets 0, or 8, laminae 4–8(–12+) mm; cypselae (4–)5–8 mm→ 5
4.Annuals (sometimes persisting); calyculi of 5–9, linear to narrowly triangular bractlets (2–)4–8+ mm; ray florets 8, laminae 10–20+ mm; cypselae 3.5–5.5+ mm→ 6
5.Plants 10–30(–50) cm; ray florets usually 8, rarely 0; disc corollas red-brownT. ambiguum
5.Plants (20–)30–80+ cm; ray florets 0; disc corollas yellowT. megapotamicum
6.Ray laminae proximally to wholly red-brown to purplish, or each with a proximal red-brown spot; disc corollas red-brown to purplish→ 7
6.Ray laminae yellow to golden (rarely proximally suffused with red-brown); disc corollas yellow or red-brown→ 8
7.Calyculi of 5–6(–9), linear to narrowly triangular bractlets (margins hispido-ciliate); cypselae 3.5–4 mmT. burridgeanum
7.Calyculi of 6–7+, narrowly triangular bractlets (margins not ciliate); cypselae 5–5.5+ mmT. nuecense
8.Plants 30–70(–120+) cm; cauline leaves ± scattered over proximal 9/10 of plant heights, internodes 35–100+ mm; disc corollas yellow, often with brown nervesT. flavodiscum
8.Plants 10–40(–70+) cm; cauline leaves crowded to ± scattered over proximal 1/2–3/4+ of plant heights, internodes mostly 10–35(–50+ mm); disc corollas red-brown or yellow with red-brown nervesT. filifolium
Synonyms Bidens megapotamica, T. gracile T. caespitosum, T. marginatum, T. pubescens, T. pubescens var. caespitosum, T. subnudum var. alpinum, T. subnudum var. marginatum, T. subnudum var. pubescens, T. windhamii
Name authority (Sprengel) Kuntze: Revis. Gen. Pl. 3(2): 182. (1898) A. Gray: Proc. Amer. Acad. Arts 10: 72. (1874) Lessing: Linnaea 6: 511. (1831)
Source Flora of North America vol. 21, p. 202. Flora of North America vol. 21, p. 201. Flora of North America vol. 21, p. 199.
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