Machaeranthera tagetina


Pittonia 4: 71. 1899.

Common names: Mesa tansyaster
Synonyms: Aster tagetinus (Greene) S. F. Blake Machaeranthera humilis (A. Gray) Standley Machaeranthera tanacetifolia var. humilis A. Gray
Treatment appears in FNA Volume 20. Treatment on page 395. Mentioned on page 394.

Annuals, 5–50 cm. Leaves 5–40 × 3–17 mm. Involucres broadly turbinate, 5–10 mm. Phyllaries 24–44 in 3–5 series, lanceolate to linear-lanceolate, 4–9 × 0.7–1.5 mm, apices usually appressed, sometimes spreading, acute to acuminate. Receptacles convex, 2–3.5 mm diam. Ray florets 8–16; laminae 6–15 × 1–3 mm. Disc florets 14–40(–45); corollas 4–7 mm, glabrous or glabrate; lobes 0.7–1 mm, hairy (hairs multicellular), 0.2–0.5 mm. Cypselae 2–3.5(–4) mm; pappi 2–8 mm. 2n = 8.

Phenology: Flowering Jul–Oct(–Dec).
Habitat: Grasslands, Larrea-dominated desert scrub, pine-oak woodlands, roadsides, streambeds
Elevation: 700–1700(–2200) m



Ariz., N.Mex., Mexico (Chihuahua, Sonora).


In the flora area, Machaeranthera tagetina occurs in southern and central Arizona and southwestern New Mexico, in the Chihuahuan and Sonoran desert regions. Much of its range in those states overlaps with that of M. tanacetifolia. In southern and central Arizona, the two species occasionally hybridize.

Selected References


Lower Taxa

... more about "Machaeranthera tagetina"
David R. Morgan +  and Ronald L. Hartman +
Greene +
Mesa tansyaster +
Ariz. +, N.Mex. +, Mexico (Chihuahua +  and Sonora). +
700–1700(–2200) m +
Grasslands, Larrea-dominated desert scrub, pine-oak woodlands, roadsides, streambeds +
Flowering Jul–Oct(–Dec). +
Aster tagetinus +, Machaeranthera humilis +  and Machaeranthera tanacetifolia var. humilis +
Machaeranthera tagetina +
Machaeranthera +
species +