Machaeranthera tagetina

Greene

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

Distribution

V20-899-distribution-map.gif

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

Discussion

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

None.

Lower Taxa

None.

"[" is not declared as a valid unit of measurement for this property."]" is not declared as a valid unit of measurement for this property.

... more about "Machaeranthera tagetina"
not tailed +, rounded +  and obtuse +
distinct +
acute;acuminate +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
David R. Morgan +  and Ronald L. Hartman +
Greene +
decurrent +
indurate +
compound +  and simple +
lanceolate;elliptic pinnatifid 2-pinnatifid deeply lobed or dissected +
rugulose +  and muricate +
white +  and tawny +
Mesa tansyaster +
not 2-lipped +  and actinomorphic +
yellow +, purple +, violet +  and blue +
glabrate +  and glabrous +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
compressed +  and obovoid +
fertile +  and bisexual +
fertile +  and bisexual +
Ariz. +, N.Mex. +, Mexico (Chihuahua) +  and Mexico (Sonora) +
700–1700(–2200) m +
hairy +, stipitate-glandular +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Grasslands, Larrea-dominated desert scrub, pine-oak woodlands, roadsides, streambeds +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (4 cm40 mm <br />0.04 m <br />) +
cauline +  and basal +
0.3 cm3 mm <br />0.003 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
deltate +  and lanceolate +
dentate to pinnatifid +  and entire +
not scarious +
2-carpellate +
persistent +
0.2 cm2 mm <br />0.002 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Flowering Jul–Oct(–Dec). +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
reflexed +, spreading +  and appressed +
lanceolate +  and linear-lanceolate +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
bearing subulate enations +, hairy +  and bristly +
exalbuminous +
stipitate-glandular +  and hairy +
appendaged +  and truncate +
papillate +  and smooth +
Aster tagetinus +, Machaeranthera humilis +  and Machaeranthera tanacetifolia var. humilis +
Machaeranthera tagetina +
Machaeranthera +
species +
5 cm50 mm <br />0.05 m <br /> (50 cm500 mm <br />0.5 m <br />) +
tree +, shrub +  and subshrub +