Thelesperma ambiguum

A. Gray

Proc. Amer. Acad. Arts 19: 16. 1883.

Synonyms: Thelesperma fraternum Shinners Thelesperma megapotamicum var. ambiguum (A. Gray) Shinners
Treatment appears in FNA Volume 21. Treatment on page 201. Mentioned on page 200.

Perennials or subshrubs, 10–30 (–50) cm. Cauline leaves crowded to ± scattered over proximal 1/3–1/2 of plant heights, internodes mostly 5–50 (–80+) mm; lobes mostly linear to filiform, sometimes oblanceolate, (5–) 15–75 × 0.5–1 (–2) mm. Calyculi of 3–5+ ovate to oblong bractlets 1–3 mm. Ray-florets usually 8, rarely 0; laminae yellow, 4–8 (–12+) mm. Disc corollas redbrown, throats shorter than lobes. Cypselae 4–5+ mm; pappi usually 1.5–2+ mm, rarely 0.2n = 44.


Phenology: Flowering Mar–Jun.
Habitat: Disturbed sites on sands or clays
Elevation: 10–200 m

Distribution

V21-494-distribution-map.gif

N.Mex., Tex., Mexico (Nuevo León), Mexico (Tamaulipas)

Discussion

Thelesperma ambiguum is similar to T. megapotamicum; it may be better treated as a variety of the latter.

Selected References

None.

Lower Taxa

None.

"broader" is not a number.

... more about "Thelesperma ambiguum"
not tailed +, rounded +  and obtuse +
dark +  and pale +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
indeterminate +  and determinate +
John L. Strother +
A. Gray +
smooth +  and ciliate or barbed +
1 +  and 2 +
subulate +
decurrent +
compound +  and simple +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
reflexed +  and spreading +
ovate;oblong +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
barbellulate +  and barbellate +
crowded +  and more or less scattered +
redbrown +, yellow +  and bicolored +
obcompressed +
fertile +  and bisexual +
fertile +  and bisexual +
N.Mex. +, Tex. +, Mexico (Nuevo León) +  and Mexico (Tamaulipas) +
10–200 m +
hairy +  and glabrous +
papillate +  and tuberculate or verrucate +
linear-fusiform;4-angled;ovate;orbiculate;oblong;linear;cuneate +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Disturbed sites on sands or clays +
discoid +  and radiate +
in loose , corymbiform arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
obcompressed +  and columnar +
5 cm50 mm <br />0.05 m <br /> (8 cm80 mm <br />0.08 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
hemispheric;urceolate +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
oblanceolate +, mostly linear +  and filiform +
unequal +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +  and 0.1 cm1 mm <br />0.001 m <br /> (?) +
dentate to pinnatifid or palmatifid +  and entire +
2-carpellate +
obovate;oblong +
persistent +
of 1-2 , smooth to ciliate or barbed awns or scales +  and coroniform +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Flowering Mar–Jun. +
2 +, 5 +  and 8 +
1/3 +  and 1/2 +
Proc. Amer. Acad. Arts +
sterile +  and fertile +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
subulate +
exalbuminous +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Thelesperma fraternum +  and Thelesperma megapotamicum var. ambiguum +
Thelesperma ambiguum +
Thelesperma +
species +
toothed +  and entire +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +