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hairy greenthread, Navajo tea

Habit Perennials, 10–30(–40+) cm (caudices often woody). Annuals, perennials, subshrubs, or shrubs, 10–400 cm (sometimes rhizomatous or with cormiform bases, stoloniferous in Coreopsis auriculata).
Leaves

usually cauline (sometimes mostly basal); usually mostly opposite (distal sometimes alternate), rarely whorled; petiolate or sessile;

blades (often pinnately or palmately lobed, sometimes compound), or lobes or leaflets, mostly deltate, elliptic, filiform, lanceolate, linear, oblanceolate, or ovate, ultimate margins entire or toothed, faces usually glabrous or glabrate, sometimes hairy (rarely, if ever, gland-dotted).

Cauline leaves

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.

Involucres

mostly campanulate, cylindric, turbinate, or hemispheric or broader.

Receptacles

mostly flat to convex, paleate (paleae often stramineous to white with red-brown to purplish striae, orbiculate to oblong or linear, ± flat to slightly cupped).

Ray florets

0, or 8;

laminae yellow, (6–)12–20+ mm.

0 or 1–21+ (more in cultivars), pistillate and fertile, or neuter, or styliferous and sterile;

corollas usually yellow to orange (sometimes bicolored: yellow to orange with brown, red-brown, or purple), sometimes cyanic or white.

Disc florets/Disc corollas

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

3–150+, usually bisexual, fertile (functionally staminate in Dicranocarpus);

corollas usually yellow to orange, sometimes brown, red-brown, or purple, tubes usually shorter than, sometimes equaling funnelform throats (longer than throats in some Thelesperma spp.), lobes (3–)5, ± deltate to lance-ovate; (staminal filaments hairy in Cosmos) anther thecae pale or dark;

stigmatic papillae in 2 lines.

Phyllaries

persistent, 3–34+ in ± 2 series (usually distinct, notably connate in Thelesperma), usually ± membranous, margins usually ± scarious.

Calyculi

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

usually of 3–8(–21+) bractlets or bracts (usually ± herbaceous, usually shorter than phyllaries and/or reflexed, sometimes ± foliaceous and surpassing phyllaries).

Heads

radiate or discoid, borne singly or in ± corymbiform, cymiform, or paniculiform arrays.

Cypselae

5–7 mm;

pappi usually 0, rarely 0.1–0.5 mm.

usually either obcompressed to obflattened, usually cuneate, linear, oblong, orbiculate, or ovate (bodies unequally 3–4-angled, margins often winged), or (all or inner) ± equally 4-angled and linear-fusiform, sometimes ± beaked, faces glabrous or hairy (often striate, tuberculate, or papillate);

pappi 0, or persistent, of (1–)2–4(–8), usually ± barbellate awns or scales, rarely coroniform or of 1–2, smooth to ciliate or barbed awns or scales.

2n

= 22, 24.

Thelesperma subnudum

Asteraceae tribe Heliantheae subtribe Coreopsidinae

Phenology Flowering May–Sep.
Habitat Openings in pinyon/juniper or yellow-pine forests, often on talus or "balds"
Elevation 1000–2900 m (3300–9500 ft)
Distribution
from FNA
AZ; CO; MT; ND; NM; NV; UT; WY; AB
[WildflowerSearch map]
[BONAP county map]
Mostly subtropical and warm-temperate New World and Old World
Discussion

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.)

Genera 20, species 374 (7 genera, 69 species in the flora).

The circumscription of Coreopsidinae followed here (H. Robinson 1981) is a bit narrower than the traditional one. The subtribe is remarkable among Heliantheae for having a relatively high number of species native in subtropical and tropical Old World, especially Africa. Distinctions among some genera (e.g., Bidens, Coreopsis, and Cosmos) are often subtle.

In Coreopsidinae, each involucre is subtended by a calyculus of more or less herbaceous (sometimes leaflike) bractlets or bracts (sometimes surpassing the phyllaries). In keys and descriptions here, shapes, heights, and diameters given for involucres are based on the phyllaries collectively (exclusive of calyculi) at flowering; the involucres are sometimes notably larger in fruit.

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

Key
1. Phyllaries (excluding calyculi) 3–6 in 1(–2) series; disc florets 3–4+ (functionally staminate)
Dicranocarpus
1. Phyllaries (3–)8–34+ in ± 2 series; disc florets 3–10, 10–20, or (5–)12–150+ (bisexual, fertile)
→ 2
2. Phyllaries connate 1/5–7/8+ their lengths
Thelesperma
2. Phyllaries usually distinct, rarely connate ± 1/10 their lengths
→ 3
3. Cypselae (at least inner) ± 4-angled, ± linear-fusiform, often apically attenuate or beaked (none winged)
→ 4
3. Cypselae all ± obcompressed (sometimes winged)
→ 5
4. Disc florets 10–20 (staminal filaments hairy near anthers); cypselae usually with 1 groove on each face
Cosmos
4. Disc florets (5–)12–150+ (staminal filaments not hairy); cypselae with 0 or 2grooves on each face
Bidens
5. Annuals; ray florets 1–3 (laminae 1–2+ mm); cypselae mostly ellipsoid orobovoid (inner obovoid to obscurely urceolate, ± beaked)
Heterosperma
5. Annuals, perennials, subshrubs, or shrubs; ray florets usually 1, 2, 3, 5, 8, 13, or 21+, sometimes 0 (laminae mostly 4–30+ mm); cypselae mostly cuneate, linear, oblanceolate, oblong, ± orbiculate, or ovate (not beaked).
→ 6
6. Cypselae rarely winged (margins sometimes thickened, winged in B. aristosa and B. polylepis); pappi usually of barbellate (rarely smooth) awns, sometimes 0
Bidens
6. Cypselae (some or all) usually thin-margined or ± winged; pappi usually 0, sometimes coroniform, or of 2 bristly cusps or scales (in Coreopsis), or of 1–2 retrorsely barbellate awns (in Coreocarpus)
→ 7
7. Ray florets usually neuter or styliferous and sterile; wings of cypselae membranous, chartaceous, or corky, entire or lobed to toothed, sometimes ciliate
Coreopsis
7. Ray florets usually pistillate and fertile; wings of cypselae ± corky, ± pectinately toothed
Coreocarpus
Source FNA vol. 21, p. 201. FNA vol. 21, p. 183.
Parent taxa Asteraceae > tribe Heliantheae > subtribe Coreopsidinae > Thelesperma Asteraceae > tribe Heliantheae
Sibling taxa
T. ambiguum, T. burridgeanum, T. filifolium, T. flavodiscum, T. longipes, T. megapotamicum, T. nuecense, T. simplicifolium
Subordinate taxa
Bidens, Coreocarpus, Coreopsis, Cosmos, Dicranocarpus, Heterosperma, Thelesperma
Synonyms T. caespitosum, T. marginatum, T. pubescens, T. pubescens var. caespitosum, T. subnudum var. alpinum, T. subnudum var. marginatum, T. subnudum var. pubescens, T. windhamii subtribe Coreopsideae, subtribe Petrobiinae
Name authority A. Gray: Proc. Amer. Acad. Arts 10: 72. (1874) Lessing: Linnaea 5: 153. (1830)
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