Tetraneuris acaulis var. acaulis

IllustratedEndemic
Synonyms: Tetraneuris eradiata A. Nelson Tetraneuris incana A. Nelson Tetraneuris pygmaea (A. Gray) Wooton & Standley Tetraneuris septentrionalis Rydberg Tetraneuris simplex A. Nelson
Treatment appears in FNA Volume 21. Treatment on page 452. Mentioned on page 451, 447, 453.

Plants (3–)10–20(–30+) cm. Leaves: blades spatulate or oblanceolate to linear-oblanceolate, usually densely, sometimes sparsely, strigoso-canescent, sparsely to moderately or densely gland-dotted. Heads 1–10(–15) per plant. Peduncles (2–)8–20(–30) cm. Outer phyllaries 6–10, 4–7 mm, margins 0–0.2(–0.4) mm wide, sometimes slightly scarious, abaxial faces usually densely hairy. Ray florets 8–14; corollas 9–15 mm. Cypselae 2.5–3 mm; pappi 2.2–2.9 mm. 2n = 28, 30, 56, 60.


Phenology: Flowering (Apr–)May–Jul(–Oct).
Habitat: Roadsides, hillsides, grasslands, edges of woods
Elevation: 700–2000(–3500) m

Distribution

V21-1135-distribution-map.gif

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

Discussion

Some plants of var. acaulis from Colorado and southeastern Wyoming have considerably less hairy and/or more densely gland-dotted leaves, making them easy to confuse with var. arizonica. As to distribution, label on a collection at LL reads, “From W. A. Curtis, Lewistown [Idaho], without definite locality but probably collected in that vicinity.” Also, the holotype and isotype of Tetraneuris septentrionalis were collected in “Palouse County, Idaho.” These are the only collections we have seen that place var. acaulis west of the continental divide.

Selected References

None.

Lower Taxa

None.
Mark W. Bierner +  and Billie L. Turner +
(Pursh) Greene +
Gaillardia acaulis +
Alta. +, Sask. +, Colo. +, Idaho +, Kans. +, Mont. +, Nebr. +, N.Mex. +, N.Dak. +, Okla. +, S.Dak. +, Tex. +  and Wyo. +
700–2000(–3500) m +
Roadsides, hillsides, grasslands, edges of woods +
Flowering (Apr–)May–Jul(–Oct). +
Illustrated +  and Endemic +
Tetraneuris eradiata +, Tetraneuris incana +, Tetraneuris pygmaea +, Tetraneuris septentrionalis +  and Tetraneuris simplex +
Tetraneuris acaulis var. acaulis +
Tetraneuris acaulis +
variety +