Tetraneuris acaulis

(Pursh) Greene

Pittonia 3: 265. 1898.

IllustratedEndemic
Basionym: Gaillardia acaulis Pursh Fl. Amer. Sept. 2: 743. 1813 (as Galardia)
Synonyms: Hymenoxys acaulis (Pursh) K. F. Parker
Treatment appears in FNA Volume 21. Treatment on page 451. Mentioned on page 447, 448.

Perennials, 2–30+ cm. Caudices ± branched, branches notably thickened distally. Stems 1–35(–60), erect, unbranched. Leaves all basal, new leaves tightly clustered; blades spatulate or oblanceolate to linear-oblanceolate, entire, glabrous or ± hairy, often lanuginose, sericeous, or strigoso-canescent, eglandular or ± gland-dotted. Heads 1–35(–60) per plant, borne singly. Peduncles 0.5–30 cm, ± hairy. Involucres 7–12 × 8–16 mm. Outer phyllaries 6–12, 3.9–9(–11.5) mm, margins 0–0.4 mm wide, sometimes slightly scarious, abaxial faces ± hairy. Ray florets 8–15(–21); corollas 9–19 mm. Disc florets 25–200+; corollas yellow, 2.7–4.3 mm. Cypselae 2–4 mm; pappi of 5–8 obovate to oblanceolate, aristate scales 2.2–3.7 mm.

Distribution

V21-1133-distribution-map.gif

Alta., Sask., Ariz., Calif., Colo., Idaho, Kans., Mont., N.Dak., N.Mex., Nebr., Nev., Okla., S.Dak., Tex., Utah, Wyo.

Discussion

Varieties 4 (4 in the flora).

Selected References

None.

Key

1 Leaves sparsely to densely hairy, often lanuginose, sometimes sericeous, not strigoso-canescent; peduncles 0.5–8(–12) cm; outer phyllaries 6.8–9(–11.5) mm; growing at (2100–)3000–3900 m Tetraneuris acaulis var. caespitosa
1 Leaves sparsely to densely hairy, often strigoso-canescent; peduncles (1–)5–20(–30) cm; outer phyllaries 4–7.5 mm; growing at 700–2900(–3500) m > 2
2 Leaf blades usually densely, sometimes sparsely, strigoso-canescent; e of continental divide (except for 2 reports from nw Idaho) Tetraneuris acaulis var. acaulis
2 Leaf blades glabrous or sparsely to moderately to sometimes densely hairy, not strigoso-canescent; w of continental divide > 3
3 Leaf blades glabrous or usually sparsely to moderately or sometimes densely hairy, densely gland-dotted; n Arizona, se California, w Colorado, s Idaho, e Nevada, Utah Tetraneuris acaulis var. arizonica
3 Leaf blades glabrous or sparsely to moderately hairy, at least some (usually most or all) eglandular or sparsely gland-dotted; w Colorado, c, ne Utah, and sw Wyoming Tetraneuris acaulis var. epunctata
... more about "Tetraneuris acaulis"
Mark W. Bierner +  and Billie L. Turner +
(Pursh) Greene +
Gaillardia acaulis +
Alta. +, Sask. +, Ariz. +, Calif. +, Colo. +, Idaho +, Kans. +, Mont. +, N.Dak. +, N.Mex. +, Nebr. +, Nev. +, Okla. +, S.Dak. +, Tex. +, Utah +  and Wyo. +
Illustrated +  and Endemic +
Hymenoxys acaulis +
Tetraneuris acaulis +
Tetraneuris +
species +