Euphorbia bifurcata

Engelmann in W. H. Emory

Rep. U.S. Mex. Bound. 2(1): 190. 1859.

Common names: Forked spurge
Illustrated
Treatment appears in FNA Volume 12. Treatment on page 319. Mentioned on page 239, 317, 318.
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Herbs, annual, with slender, fibrous taproot. Stems erect, 20–70 cm, glabrous or with few scattered spreading hairs; branches arcuate, branching appearing dichotomous. Leaves usually alternate, occasionally opposite at proximalmost node; petiole 15–49 mm, glabrous; blade usually ovate, rarely oblong or elliptic, 13–54 × 7–38 mm, base usually rounded to broadly cuneate, rarely truncate, margins finely serrulate, apex obtuse, surfaces glabrous or with few scattered hairs; venation pinnate, midvein prominent. Cyathial arrangement: terminal dichasial branches 2, few-branched (weakly defined); pleiochasial bracts 2–3, opposite or whorled, wholly green, similar in shape and size to distal leaves; dichasial bracts smaller than distal leaves, often white at base. Cyathia: peduncle 0.9–3.5 (–6.2) mm. Involucre tubular or obconic, 1–1.7 × 0.7–1.4 mm, glabrous except for few hairs on lobes; involucral lobes divided into several linear, smooth lobes; glands 1 (–3), greenish, sessile and broadly attached, 0.3–0.4 × 0.4–0.8 mm, opening oblong to subcircular, glabrous; appendages petaloid, white, elliptic, oblong, transversely oblong, or forming thin, lunate rim on gland margin, not incurved and covering glands, 0.3–0.9 × 0.6–1.3 mm, entire, undulate or slightly lobed, glabrous. Staminate flowers 20–30. Pistillate flowers: ovary glabrous; styles 0.6–1 mm, 2-fid 1/2 length. Capsules oblate, 2.8–3.1 × 3.6–4.5 mm, glabrous; columella 1.9–2.4 mm. Seeds brown to blackish, ovoid, rounded in cross-section, 1.9–2.4 × 1.5–1.8 mm, irregularly and coarsely tuberculate; caruncle absent or rudimentary.


Phenology: Flowering and fruiting summer–fall.
Habitat: Riparian areas with cottonwoods and willows, pinyon pine woodlands, pine-oak forests, Douglas fir forests with pines.
Elevation: 1900–2300 m.

Distribution

V12 702-distribution-map.jpg

N.Mex., Tex., Mexico, Central America (Guatemala)

Discussion

Euphorbia bifurcata is found in the mountains of southern New Mexico (Doña Ana, Grant, Lincoln, Otero, and Sierra counties) and trans-Pecos Texas (Brewster, Jeff Davis, and Presidio counties).

Selected References

None.

Lower Taxa

None.

"connate" is not a number. "distinct" is not a number."/2" is not declared as a valid unit of measurement for this property.

... more about "Euphorbia bifurcata"
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
lobed +, undulate +, entire +  and oblong +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
Jess A. Peirson +, Paul E. Berry +  and Victor W. Steinmann +
Engelmann in W. H. Emory +
connate +
usually rounded +  and broadly cuneate +
Poinsettia +
1.3 cm13 mm <br />0.013 m <br /> (5.4 cm54 mm <br />0.054 m <br />) +
elliptic;oblong;ovate +
0.7 cm7 mm <br />0.007 m <br /> (3.8 cm38 mm <br />0.038 m <br />) +
dichasial +  and pleiochasial +
whorled +  and opposite +
white +  and green +
distinct +
2 +  and 3 +
smaller +
dichotomous +  and branching +
arranged +  and opposite +
additional +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.31 cm3.1 mm <br />0.0031 m <br />) +
0.36 cm3.6 mm <br />0.0036 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.24 cm2.4 mm <br />0.0024 m <br />) +
Forked spurge +
N.Mex. +, Tex. +, Mexico +  and Central America (Guatemala) +
1900–2300 m. +
pistillate +  and staminate +
0.3mm;0.4mm +
subtending +
oblong +  and subcircular +
0.4mm +  and 0.8mm +
Riparian areas with cottonwoods and willows, pinyon pine woodlands, pine-oak forests, Douglas fir forests with pines. +
axillary +  and terminal +
0.1 cm1 mm <br />0.001 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
obconic +  and tubular +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
caducous +, deciduous +  and persistent +
bractlike +
involucral +
divided +
palmate +  and pinnate +
toothed flat +  and revolute +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.62 cm6.2 mm <br />0.0062 m <br />) +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
connate;distinct +
1.5 cm15 mm <br />0.015 m <br /> (4.9 cm49 mm <br />0.049 m <br />) +
Flowering and fruiting summer–fall. +
Rep. U.S. Mex. Bound. +
lunate +
brown;blackish +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.24 cm2.4 mm <br />0.0024 m <br />) +
tuberculate +
rounded +  and ovoid +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
Illustrated +
free +, connate +  and distinct +
with few scattered spreading hairs +  and glabrous +
20 cm200 mm <br />0.2 m <br /> (70 cm700 mm <br />0.7 m <br />) +
deciduous +  and persistent +
distinct +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (?) +  and 0.1 cm1 mm <br />0.001 m <br /> (?) +
with few scattered hairs +  and glabrous +
Euphorbia bifurcata +
Euphorbia sect. Poinsettia +
species +
few-branched +  and dichasial +