Euphorbia lurida |
Euphorbia parishii |
|
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woodland spurge |
Parish's sandmat |
|
Habit | Herbs, perennial, with thick rootstock. | Herbs or subshrubs, perennial, with thickened and often woody rootstock. |
Stems | erect or ascending, unbranched, sometimes sinuous, 5–30 cm, glabrous or sparsely to densely puberulent. |
prostrate, sometimes forming dense mounds, 10–50 cm, glabrous. |
Leaves | petiole 0–1 mm; blade oblanceolate to obovate, 8–20 mm × 3–7 mm, base truncate or cuneate, margins entire, apex obtuse to rounded, minutely mucronate, surfaces puberulent or glabrous; venation inconspicuous, only midvein prominent. |
opposite; stipules distinct, subulate-filiform, 0.3–0.9 mm, pilose; petiole 0.3–1.2 mm, glabrous; blade usually ovate, rarely oblong, 2–7 × 1–5 mm, base usually asymmetric, rounded to hemicordate, margins entire, apex usually obtuse, rarely acute, surfaces glabrous; only midvein conspicuous. |
Involucre | cupulate, 2–2.2 × 1.3–1.8 mm, glabrous; glands 4, oblong to broadly ovate, usually truncate, 0.5–0.8 × 1–1.6 mm, margins irregularly crenate to strongly dentate; horns absent or usually divergent or straight, 0.1–0.3 mm, usually slightly longer than, occasionally equaling, teeth on gland margin. |
obconic to campanulate, 1–1.4 × 0.9–1.3 mm, glabrous except for pilose lobes; glands 4, pink to maroon, circular, 0.3–0.4 × 0.3–0.4 mm; appendages absent. |
Staminate flowers | 10–20. |
40–50. |
Pistillate flowers | ovary glabrous or puberulent; styles 0.7–1 mm, 2-fid. |
ovary glabrous; styles 0.3–0.6 mm, 2-fid 1/2 length. |
Capsules | ovoid, 3.5–4 × 4–4.5 mm, 3-lobed; cocci rounded, smooth to slightly rugose, glabrous; columella 3.2–3.5 mm. |
ovoid to oblate-ovoid, 1.6–1.7 × 1.6–1.9 mm, glabrous; columella 1.2–1.5 mm. |
Seeds | gray to dark gray, truncate-oblong to truncate-ovoid, 2.8–3 × 1.7–2 mm, irregularly pitted; caruncle conic, 0.6 × 0.7 mm. |
whitish to light brown, ovoid, 4-angled in cross section, 1.2–1.4 × 0.6–0.8 mm, rugose or with indistinct, irregular, low transverse ridges. |
Cyathial | arrangement: terminal pleiochasial branches 3–5, each 1–4 times 2-branched; pleiochasial bracts ovate to broadly ovate or oblanceolate, wider than distal leaves; dichasial bracts distinct, rounded, oblanceolate, or subreniform, base cuneate or obtuse, margins entire, apex obtuse, slightly mucronate; axillary cymose branches 0–4. |
|
Cyathia | peduncle 0.3–0.9 mm. |
solitary at distal nodes; peduncle 0.1–0.6(–2.2) mm. |
Euphorbia lurida |
Euphorbia parishii |
|
Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting fall–summer. |
Habitat | Open pine-oak forests, dry slopes and canyons. | Desert scrub, often with creosote bush, disturbed roadsides, rocky soils. |
Elevation | 1300–2800 m. (4300–9200 ft.) | -90–600 m. (-300–2000 ft.) |
Distribution |
AZ; CA; NM; NV; UT; Mexico (Baja California)
|
CA; NV |
Discussion | Euphorbia lurida has been treated as a complex of several taxa in the past, but only a single, broadly-defined species is recognized here. This species is variable in both the pubescence and shape of the bracts subtending the cyathia and also in the degree of crenation of the gland margin. In the northern part of its range, E. lurida appears to intergrade with E. brachycera, and it can be difficult to distinguish these two species in northern Arizona and New Mexico. A report of the species from Sonora, Mexico, based on a single immature collection (V. W. Steinmann and R. S. Felger 1997) has not been verified. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia parishii is common in the Death Valley region of southern California, where it is often encountered well below sea level. The species is frequently confused with E. micromera and E. polycarpa but differs from the former in being a more robust plant with larger cyathia and from the latter in lacking involucral gland appendages. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 305. | FNA vol. 12, p. 280. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | E. palmeri, E. palmeri var. subpubens, E. subpubens, Tithymalus luridus, T. palmeri, T. subpubens | Chamaesyce parishii, E. polycarpa var. parishii |
Name authority | Engelmann: in J. C. Ives, Rep. Colorado R. 4: 26. (1861) | Greene: Bull. Calif. Acad. Sci. 2: 56. (1886) |
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