Euphorbia serrula

Engelmann in W. H. Emory

Rep. U.S. Mex. Bound. 2(1): 188. 1859.

Common names: Sawtooth sandmat
Synonyms: Chamaesyce serrula (Engelmann) Wooton & Standley
Treatment appears in FNA Volume 12. Treatment on page 288. Mentioned on page 256.

Herbs, annual, with slender taproot. Stems prostrate or ascending, 5–20 cm, usually pilose to villous, rarely glabrate. Leaves opposite; stipules usually distinct, rarely connate at base, triangular or laciniate into subulate segments, 1–1.8 mm, glabrous; petiole 0.3–0.8 mm, glabrous or villous; blade oblong, ovate, or elliptic, sometimes falcate, 3–11 × 2–5 mm, base asymmetric, rounded to hemicordate, margins sharply serrate to serrulate, usually with conspicuous teeth at base of leaf, apex usually obtuse, rarely acute, surfaces frequently with red blotch in center, not papillate, sparsely pilose to glabrate; only midvein conspicuous. Cyathia solitary at distal nodes; peduncle 0.4–1.8 (–2.3) mm. Involucre obconic, 0.8–1.1 × 0.8–1 mm, glabrous; glands 4, greenish yellow, usually reniform to elliptic, rarely circular, 0.1 × 0.1–0.2 mm; appendages usually white, rarely light pink, orbiculate, 0.1–0.3 × 0.2–0.4 mm, distal margin entire or crenulate. Staminate flowers 7–15. Pistillate flowers: ovary glabrous; styles 0.3–0.5 mm, 2-fid 1/2 length. Capsules oblate, cocci not elongated nor terminating in empty portion, 2–2.6 × 3.2–3.7 mm, glabrous; columella 1.7–2.1 mm. Seeds white to light-brown, broadly ellipsoid to ovoid, 3–4-angled in cross-section, 1.5–1.8 × 1.1–1.3 (–1.5) mm, smooth to minutely rugulose or with scattered small depressions.


Phenology: Flowering and fruiting spring–fall.
Habitat: Desert scrub, with creosote bush, grasslands with mesquite and yucca, rarely in ponderosa pine woodlands, often sandy substrates.
Elevation: 300–1900 m.

Distribution

V12 417-distribution-map.jpg

Ariz., N.Mex., Tex., Mexico

Discussion

In Mexico, Euphorbia serrula is found from Chihuahua and Coahuila south to Puebla.

Selected References

None.

Lower Taxa

None.
... more about "Euphorbia serrula"
light pink;white +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
orbiculate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Victor W. Steinmann +, Jeffery J. Morawetz +, Paul E. Berry +, Jess A. Peirson +  and Ya Yang +
Engelmann in W. H. Emory +
rounded +
Anisophyllum +
0.3 cm3 mm <br />0.003 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
falcate;elliptic;ovate;elliptic;ovate;oblong +
2mm;5mm +
not elongated +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
Sawtooth sandmat +
crenulate +  and entire +
Ariz. +, N.Mex. +, Tex. +  and Mexico +
300–1900 m. +
pistillate +  and staminate +
greenish yellow +
subtending +
reniform to elliptic +  and reniform +
0.1mm +  and 0.2mm +
Desert scrub, with creosote bush, grasslands with mesquite and yucca, rarely in ponderosa pine woodlands, often sandy substrates. +
axillary +  and terminal +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
caducous +, deciduous +  and persistent +
bractlike +
palmate +  and pinnate +
sharply serrate +  and serrulate +
toothed +  and entire +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
connate;distinct +
villous +  and glabrous +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Flowering and fruiting spring–fall. +
0.2 cm2 mm <br />0.002 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
0.32 cm3.2 mm <br />0.0032 m <br /> (0.37 cm3.7 mm <br />0.0037 m <br />) +
Rep. U.S. Mex. Bound. +
3-4-angled +, broadly ellipsoid +  and ovoid +
free +, connate +  and distinct +
ascending +  and prostrate +
flattened +  and terete +
5 cm50 mm <br />0.05 m <br /> (20 cm200 mm <br />0.2 m <br />) +
connate +  and distinct +
interpetiolar +
? (?) +  and ? (?) +
0.1 cm1 mm <br />0.001 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
connate +  and distinct +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (?) +  and 0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +
sparsely pilose +  and glabrate +
not papillate +
Chamaesyce serrula +
Euphorbia serrula +
Euphorbia sect. Anisophyllum +
species +
conspicuous +
axillary +  and terminal +
10 +, 9 +, 8 +, 7 +  and 6 +