Bidens leptocephala

Sherff

Bot. Gaz. 64: 22. 1917.

Treatment appears in FNA Volume 21. Treatment on page 209. Mentioned on page 207.

Annuals, 10–25 (–50) cm. Leaves: petioles 5–40 mm (usually hispido-ciliate); blades rounded-deltate overall, 15–50+ × 12–40+ mm, 1–2-pinnatisect, ultimate lobes ovate or lanceolate to linear, 3–25+ × (1–) 2–3 (–15) mm, bases ± cuneate, ultimate margins entire, ciliolate, apices acute to attenuate, faces glabrous or hirtellous. Heads usually borne singly, sometimes in open, ± corymbiform arrays. Peduncles (10–) 30–80+ mm. Calyculi of 3–4 (–6) ± appressed, subulate to filiform bractlets 1–3 mm, margins ciliolate, abaxial faces usually glabrous. Involucres ± cylindric, 2–3 (–4+) × 1.5–2+ mm. Phyllaries 4–5 (–7), oblong to lanceolate, (2–) 3–4+ mm. Ray-florets 0 or 2–3; laminae yellowish or whitish, 1–3 mm. Disc-florets 5–13; corollas yellowish to whitish, 1.5–2 mm. Cypselae: outer redbrown, flat or unequally 4-angled, linear, 6–8 mm, margins not ciliate, apices somewhat attenuate, faces obscurely 2-grooved, antrorsely hispidulous toward tips; inner similar, blackish (sometimes with pale tips), ± equally 4-angled, linear-fusiform, 9–14 mm, margins not ciliate, apices attenuate, faces 2-grooved, antrorsely hispidulous (at least distally); pappi of 2 (–3), erect, retrorsely barbed awns 1–3 mm.


Phenology: Flowering Sep.
Habitat: Along streams
Elevation: 900–1800 m

Distribution

V21-509-distribution-map.gif

Ariz., N.Mex., Tex., Mexico (Baja California), Mexico (Chihuahua)

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Bidens leptocephala"
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 +  and Ronald R. Weedon +
Sherff +
ciliate +  and barbellate +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
cuneate +
compound +  and simple +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
rounded-deltate +
12mm;40mm +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
erect +  and spreading or reflexed +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
barbellulate +  and barbellate +
yellowish +  and whitish +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
subterete +, linear-fusiform +, 4-angled +, cuneate +  and oblanceolate or obovate +
fertile +  and bisexual +
fertile +  and bisexual +
sessile +  and petiolate +
Ariz. +, N.Mex. +, Tex. +, Mexico (Baja California) +  and Mexico (Chihuahua) +
900–1800 m +
hispidulous +, hirtellous +  and glabrous +
tuberculate +, striate +  and scabrellous +
linear-fusiform;4-angled;ovate;orbiculate;oblong;linear;cuneate +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Along streams +
discoid +  and radiate +
disciform +  and discoid +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
linear-fusiform +  and 4-angled +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
whitish +  and yellowish +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
sessile +  and petiolate +
whorled +  and opposite +
deltate +
4-angled +  and flat +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
2-carpellate +
less flat;slightly navicular +
persistent +
of 1-2 , smooth to ciliate or barbed awns or scales +  and coroniform +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (4 cm40 mm <br />0.04 m <br />) +
Flowering Sep. +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
connate +  and distinct +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
styliferous +  and neuter +
bearing subulate enations +, hairy +  and bristly +
convex;flat +
exalbuminous +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Megalodonta +
Bidens leptocephala +
species +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
lanceolate;linear +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
toothed +, serrate +, laciniate +  and dentate +
25 cm250 mm <br />0.25 m <br /> (50 cm500 mm <br />0.5 m <br />) +
10 cm100 mm <br />0.1 m <br /> (25 cm250 mm <br />0.25 m <br />) +
shrub +  and subshrub +