Euphorbia eriantha |
Euphorbia cinerascens |
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beetle spurge |
ashy sandmat |
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Habit | Herbs, annual or perennial, with slender to thick, woody taproot. | Herbs, perennial, with moderately to strongly thickened rootstock. |
Stems | erect to ascending, 10–75 cm, glabrous or with scattered appressed hairs (especially near nodes); branches arcuate. |
prostrate to decumbent, mat-forming, 5–30 cm, appressed wooly, strigillose, or short-sericeous. |
Leaves | alternate; petiole 0.1–0.4 mm, often indistinct, glabrous or sparsely pilose to shortly sericeous; blade linear to linear-elliptic, 20–55 × 1–3 mm, base attenuate, margins entire or with 2–4 inconspicuous teeth near apex, apex acute, abaxial surface pilose to shortly sericeous, adaxial surface usually glabrous, rarely pilose to shortly sericeous; only midvein conspicuous. |
opposite; stipules distinct, subulate, 0.2–0.5 mm, appressed wooly to sericeous; petiole 0.3–0.8 mm, appressed wooly to sericeous; blade ovate to elliptic, 1.5–5.5 × 1.3–4 mm, base asymmetric, obtuse to hemicordate, margins entire often reddish, apex usually obtuse, occasionally acute (young leaves), surfaces sericeous to strigillose or slightly pilose, adaxial surface often glabrous; 3-veined from base but only midvein conspicuous. |
Involucre | obconic, 2.1–2.6 × 1.3–2 mm, canescent; involucral lobes triangular, obscured by hairs; glands (2–)4–5, green to maroon, color often obscured by hairs, sessile and broadly attached, 0.5–0.6 × 0.5–0.6 mm, opening oblong to nearly circular, densely canescent; appendages petaloid, whitish, hoodlike, incurved and covering glands, 0.5–1 × 0.5–0.8 mm, divided into 5–12 fringed, subulate segments, densely canescent. |
turbinate, 0.8–1.3 × 1.2–2 mm, appressed wooly, sericeous, or strigillose; glands 4, purple-black, elliptic to oblong, 0.2–0.3 × 0.4–0.6 mm; appendages absent or reddish pink, forming narrow rim around distal margin of gland, 0–0.1 × 0–0.6 mm, distal margin entire, crenulate, or erose. |
Staminate flowers | 20–25. |
15–20. |
Pistillate flowers | ovary canescent; styles 0.9–1.5 mm, unbranched. |
ovary canescent; styles 0.3–0.5 mm, 2-fid at apex. |
Capsules | oblong to ovoid, 4.4–4.9 × 3.5–4.1 mm, canescent (often with interspersed glabrescent patches); columella 3.5–3.9 mm. |
subglobose to broadly ovoid, 1.3–1.7 × 1.5–1.8 mm, canescent; columella 1–1.3 mm. |
Seeds | mottled black and gray or light brown, oblong or slightly ovoid, dorsiventrally compressed in cross section, 2.8–4.1 × 2–2.4 mm, irregularly pitted and tuberculate; caruncle 0.4–0.8 × 0.6–1.1 mm. |
white to pinkish or light brown, ovoid, 4-angled in cross section, 1–1.4 × 0.6–0.8 mm, smooth to rugulose or rarely with 1–2 inconspicuous transverse ridges. |
Cyathial | arrangement: terminal cymose branches 1, 1–2-branched; pleiochasial bracts 2–3, opposite or whorled, wholly green, similar in shape and size to distal leaves; dichasial bracts similar in shape to distal leaves or often highly reduced. |
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Cyathia | peduncle 1–1.9 mm. |
solitary at distal nodes; peduncle 0.2–0.3 mm. |
2n | = 32. |
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Euphorbia eriantha |
Euphorbia cinerascens |
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Phenology | Flowering and fruiting year-round in response to sufficient rainfall. | Flowering and fruiting year-round (mostly spring–fall). |
Habitat | Desert scrub on rocky slopes and along washes. | Desert scrub, oak and juniper woodlands, thorn scrub, shrublands, grasslands, frequently on limestone substrates. |
Elevation | 60–800 m. (200–2600 ft.) | 70–1400 m. (200–4600 ft.) |
Distribution |
AZ; CA; NM; TX; Mexico (Baja California, Baja California Sur, Chihuahua, Coahuila, Durango, San Luis Potosí, Sonora)
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TX; Mexico |
Discussion | In the flora area, Euphorbia cinerascens is found only in southern and western Texas. In Mexico, it is found from Chihuahua east to Tamaulipas, south to Guanajuato. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 321. | FNA vol. 12, p. 264. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Poinsettia | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce cinerascens | |
Name authority | Bentham: Bot. Voy. Sulphur, 51. (1844) | Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 186. (1859) |
Web links |