Euphorbia myrsinites |
Euphorbia polygonifolia |
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broad leaf glaucous spurge, donkey tail, myrtle or creeping or blue spurge, myrtle spurge |
dune spurge, euphorbe à feuilles de renouée, seaside sandmat, seaside spurge |
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Habit | Herbs, usually perennial, occasionally biennial, with taproot. | Herbs, annual, with taproot. |
Stems | erect or semiprostrate, unbranched or branched, 15–40 cm, succulent, glabrous. |
usually prostrate, occasionally ascending, 5–30 cm, glabrous. |
Leaves | petiole 0–2 mm; blade obovate, obovate-oblong, lanceolate, orbiculate, or suborbiculate, 2–30 × 3–17 mm, fleshy, base truncate or attenuate, margins entire or finely denticulate, apex acute to obtuse, cuspidate or strongly mucronate, surfaces glabrous; venation and midvein inconspicuous. |
opposite; stipules usually distinct, occasionally connate basally (distal portion of stem), triangular-subulate, entire or divided, 0.8–1.5 mm, glabrous; petiole 1–3 mm, glabrous; blade oblong, linear-oblong, or linear-lanceolate, 5–16 × 2–4 mm, base slightly asymmetric, obtuse or subcordate, margins entire, apex obtuse, often mucronulate, surfaces uniformly green or reddish tinged, glabrous; venation obscure. |
Involucre | campanulate, 2.4–2.6 × 2.3–2.5 mm, glabrous; glands 4, trapezoidal, 1–1.5 × 1.5–2.5 mm; horns divergent, thick, tips rounded, dilated, 0.5–0.9 mm. |
obconic-campanulate, 1.2–1.7 × 1–1.4 mm, glabrous; glands 4, occasionally rudimentary, green-yellow to tan or orange-tinged, occasionally shortly stipitate, usually broadly oval to subcircular, sometimes figure eight-shaped, shallowly cupped, 0.1–0.3 × 0.2–0.4 mm; appendages absent or rudimentary. |
Staminate flowers | 6–12. |
5–14. |
Pistillate flowers | ovary glabrous; styles 2.5–2.8 mm, usually unbranched. |
ovary glabrous; styles 0.7–1 mm, 2-fid 1/2 length. |
Capsules | subglobose, 5–7 × 5–6 mm, unlobed; cocci rounded to subangular, smooth, glabrous; columella 4.5–5 mm. |
broadly ovoid, 3–3.5(–4) × (2–)2.4–3 mm, glabrous; columella 2–3 mm. |
Seeds | brownish to grayish, oblong, 2.8–4.5 × 2–3.2 mm, vermiculate-rugose; caruncle substipitate, trapezoidal or mushroom-shaped, 1.3–1.5 × 0.6–0.8 mm. |
ashy white, wedge-shaped to slightly ovoid, weakly dorsiventrally compressed and elliptic-terete to bluntly subangled in cross section, back strongly rounded, face slightly rounded, (2–)2.2–2.8 × 1.6–1.9 mm, smooth or minutely pitted, with smooth brown line from top to bottom on adaxial side. |
Cyathial | arrangement: terminal pleiochasial branches 2–12, each 1–2 times 2-branched; pleiochasial bracts similar in shape and size to distal leaves; dichasial bracts distinct, suborbiculate or reniform, base truncate, margins entire or minutely denticulate, apex obtuse, mucronulate; axillary cymose branches 0–4. |
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Cyathia | peduncle 0.5–1 mm. |
solitary or in small, cymose clusters at distal nodes; peduncle 0.5–5 mm. |
Euphorbia myrsinites |
Euphorbia polygonifolia |
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Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting early summer–fall. |
Habitat | Scrub oak communities, open ground near forests, shrub-steppes. | Sandy maritime and freshwater beaches and foredunes. |
Elevation | 0–2400 m. (0–7900 ft.) | 0–200 m. (0–700 ft.) |
Distribution |
CA; CO; ID; MT; NM; OR; UT; WA; WY; BC; s Europe; w Asia [Introduced in North America]
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CT; DE; FL; GA; IL; IN; MA; MD; ME; MI; NC; NH; NJ; NY; OH; PA; RI; SC; VA; WI; NB; NS; ON; PE; QC
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Discussion | Euphorbia myrsinites is cultivated in much of the flora area, where it can tolerate cold winters. In some areas, it can locally escape from cultivation. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia polygonifolia is native to coastal beaches and dunes along the Atlantic Ocean from the maritime provinces of Canada south to northern Florida. The species also occurs disjunctly along the shores of the North American Great Lakes. Euphorbia polygonifolia was native to Quebec but is now considered extirpated from the province. It has apparently been introduced in Europe, but it is unclear if it has persisted there (L. C. Wheeler 1941). Immature individuals of this species can be somewhat difficult to distinguish from E. bombensis where their ranges overlap (Virginia to northern Florida). Where they occur together, E. polygonifolia tends to be a pioneer species on the upper beach and foredune front, whereas E. bombensis tends to inhabit areas behind the foredune (R. D. Porcher and D. A. Rayner 2002). Euphorbia polygonifolia can be distinguished also by its larger capsules and larger, wedge-shaped to slightly ovoid seeds. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 305. | FNA vol. 12, p. 284. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Tithymalus myrsinites | Chamaesyce polygonifolia |
Name authority | Linnaeus: Sp. Pl. 1: 461. (1753) | Linnaeus: Sp. Pl. 1: 455. (1753) |
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