Euphorbia bicolor |
Euphorbia mesembrianthemifolia |
|
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snow-on-the-prairie |
coastal beach sandmat |
|
Habit | Herbs, annual, with taproot. | Subshrubs or shrubs, perennial, with thickened and often woody rootstock. |
Stems | erect, unbranched or branched, 40–100 cm, pilose. |
erect to ascending, or nearly decumbent in shifting sand, 25–60 cm, glabrous. |
Leaves | alternate; stipules 0.3–0.4 mm; petiole 0.3–1 mm, pilose; blade narrowly elliptic to lanceolate, 37–54 × 7–17 mm, base cuneate to slightly rounded, margins entire, apex aristate or acute, surfaces pilose; venation obscure, only midvein conspicuous. |
opposite; stipules connate, forming conspicuous, ligulate or deltate scale, short cleft or fringed, 1–1.8 mm, glabrous; petiole 0.5–1 mm, glabrous; blade ovate to elliptic often folded along midrib, 5–12 × 3–8 mm, ± fleshy, base slightly asymmetric, truncate to cordate, partially obscuring stem, margins entire, apex usually obtuse, rarely acute, surfaces yellowish to dark green, glabrous glaucous; obscurely 3–5-veined at base, pinnate distally, only midvein conspicuous. |
Involucre | campanulate, 2.7–3.5 × 2.2–3 mm, densely pilose; glands 4–5, green to pale greenish yellow, reniform, 0.6–0.7 × 1.4–1.6 mm; appendages white, obdeltate to orbiculate, 1.4–2.5 × 1.7–3 mm, dentate to erose. |
campanulate, 1–1.6 × 0.7–1.2 mm, glabrous; glands 4, brown, usually elliptic, occasionally almost round, 0.2–0.4 × 0.5–0.7 mm, fleshy; appendages white, oblong, rarely rudimentary, 0.2–0.4 × 0.5–0.9 mm, distal margin entire or undulate. |
Staminate flowers | 30–70. |
12–20. |
Pistillate flowers | ovary pilose; styles 0.7–1.2 mm, 2-fid 1/2 length. |
ovary glabrous; styles 0.3–0.4 mm, 2-fid 1/2 length. |
Capsules | depressed-ovoid, 3.5–7.5 × 6–8.7 mm, densely pilose; columella 4.5–5.5 mm. |
subglobose subtended by calyxlike structure, 1.5–2 × 2.2–2.8 mm, glabrous; columella 1–1.5 mm. |
Seeds | tan to brown, ovoid, 4.3–4.5 × 3.7–3.9 mm, alveolate; caruncle absent. |
ashen, broadly ovoid, angled in cross section, faces plump, convex, 1.2–1.3 × 0.9–1.2 mm, obscurely pitted. |
Cyathia | in terminal pleiochasia dichasial and pleiochasial bracts linear to narrowly oblanceolate, with conspicuous white margins; peduncle 1.2–3 mm, densely pilose. |
solitary at distal nodes; peduncle 0.5–1 mm. |
Euphorbia bicolor |
Euphorbia mesembrianthemifolia |
|
Phenology | Flowering and fruiting summer–fall. | Flowering and fruiting year-round. |
Habitat | Prairies, blackland (calcareous) prairies, pastures and clearings in former blackland prairie areas, roadside clearings. | Sandy and rocky shores, associated beach scrub. |
Elevation | 100–200 m. (300–700 ft.) | 0–10 m. (0–0 ft.) |
Distribution |
AR; LA; OK; TX
|
FL; Mexico; West Indies; Bermuda; South America (Colombia, Venezuela) |
Discussion | Euphorbia bicolor is similar in appearance to E. marginata but can be distinguished by its linear to narrowly oblanceolate bracts and the presence of hairs on all parts of the plant. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia mesembrianthemifolia is found in the flora area along the sandy and rocky shores of southern Florida from Pinellas and Volusia counties southward. It is one of the few members of subg. Chamaesyce in the flora area that is a shrub or subshrub. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 243. | FNA vol. 12, p. 277. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Alectoroctonum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce buxifolia, C. mesembrianthemifolia, E. buxifolia | |
Name authority | Engelmann & A. Gray: Boston J. Nat. Hist. 5: 233. (1845) | Jacquin: Enum. Syst. Pl., 22. (1760) |
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