Euphorbia exserta |
Euphorbia peplus |
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coastal sand spurge, maroon or purple sand spurge |
petty spurge |
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Habit | Herbs, perennial, with spreading rootstock. | Herbs, annual, with taproot. |
Stems | erect or ascending, unbranched or branched, solitary, few, or occasionally densely clumped, previous year's dead stems not persistent, 20–33 cm, usually glabrous, rarely sparsely villous, glaucescent. |
erect, unbranched or branched, 5–30 cm, glabrous. |
Leaves | alternate; stipules less than 0.1 mm; petiole (0–)1–3 mm, glabrous; blade linear or linear-elliptic to obovate or orbiculate, proximal greatly reduced, scalelike, 15–30 × 1–20 mm, base cuneate to rounded, margins entire, apex rounded, broadly acute, or emarginate, surfaces glabrous, glaucescent; venation often obscure on narrow leaves, midvein conspicuous. |
petiole 1–10 mm; blade obovate, oblong, or suborbiculate, 5–25 × 4–15 mm, base attenuate or cuneate, margins entire, apex obtuse, surfaces glabrous; venation pinnate, midvein prominent. |
Involucre | usually dark red, campanulate, 1.3–1.6 × 1.4–2.1 mm, glabrous; glands 5, usually dark red, rarely greenish red, elliptic reniform, thickened, 0.3–0.5 × 0.8 mm; appendages white or green, often forming narrow rim around distal margin of gland, 0–0.2 mm, entire. |
cupulate to slightly turbinate, 0.6–1.1 × 0.7–0.9 mm, glabrous; glands 4, elliptic, 0.2–0.3 × 0.5–0.6 mm; horns slightly convergent to divergent, 0.4–0.6 mm. |
Staminate flowers | 20–25. |
10–15. |
Pistillate flowers | ovary glabrous; styles 0.4–0.8 mm, 2-fid at apex. |
ovary glabrous; styles 0.1–0.2 mm, 2-fid. |
Capsules | depressed-globose, 1.8–2.5 × 3.6–4.4 mm, glabrous; columella 1.9–2.4 mm. |
subglobose, 1.3–2 × 1.5–2.2 mm, slightly 3-lobed; cocci rounded, with 2 low longitudinal wings, smooth, glabrous; columella 1.1–1.3 mm. |
Seeds | ashy white, ovoid, 2.1 × 1.3 mm, angled with 5 blunt longitudinal ridges, with shallow and irregular pits; caruncle absent. |
whitish or grayish, subovoid, 1–1.6 × 0.6–1 mm, abaxial faces regularly large-pitted (appearing almost alveolate), adaxial faces longitudinally sulcate; caruncle deciduous, conic, 0.2–0.5 × 0.2–0.7 mm. |
Cyathia | usually in terminal dichasia, sometimes pleiochasia; peduncle 6–33 mm, filiform, glabrous. |
peduncle 0.4–1.1 mm. |
Cyathial | arrangement: terminal pleiochasial branches 3–5, usually 2–8 times 2-branched, 1st branching level rarely 3-furcate; pleiochasial bracts similar in shape to and slightly larger than distal leaves; dichasial bracts distinct, ovate to obovate, base obtuse, margins entire, apex obtuse, usually mucronate; axillary cymose branches 0–3. |
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Euphorbia exserta |
Euphorbia peplus |
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Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting year-round. |
Habitat | Xeric to dry pine-oak scrub of sand hills, pine-oak woodlands, pine-oak savannas. | Edges of gardens, weedy flower beds, roadsides, waste places, open ground near forests. |
Elevation | 0–150 m. (0–500 ft.) | 0–1500 m. (0–4900 ft.) |
Distribution |
FL; GA; NC; SC; VA
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AL; AZ; CA; CO; CT; DE; IA; ID; IL; IN; KY; LA; MA; MD; ME; MI; MT; NC; ND; NH; NJ; NM; NV; NY; OH; OR; PA; RI; TN; TX; UT; VA; VT; WA; WI; WV; AB; BC; MB; NB; NF; NS; ON; PE; QC; SK; Europe; w Asia [Introduced in North America; introduced also in Mexico, West Indies, Bermuda, Central America, South America, Africa, Atlantic Islands, Indian Ocean Islands, Pacific Islands, Australia]
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Discussion | K. R. Park (1998) recognized both Euphorbia exserta and E. gracilior as distinct species, with the former known only from the holotype. However, this treatment follows M. J. Huft (1997) and treats E. gracilior as a synonym of E. exserta. Although the type of E. exserta is unusual in having greenish red (versus dark red) cyathia and glands, as well as small gland appendages, it is otherwise typical of the species as a whole, including features such as the upright habit, reddish coloration, scalelike proximal leaves, and filiform peduncles to 30 mm that are also common to plants formerly treated as E. gracilior. Euphorbia gracilis Elliott, which has sometimes been applied to E. exserta, is an illegitimate name (a later homonym of E. gracilis Loiseleur-Deslongchamps) and pertains here. The upright habit and usually dark red cyathia and glands distinguish Euphorbia exserta from the otherwise similar E. ipecacuanhae, while the glaucescent vegetative parts and smaller gland appendages readily separate E. exserta from the similar E. curtisii. Euphorbia exserta is found on the Gulf and Atlantic coastal plains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 246. | FNA vol. 12, p. 307. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Alectoroctonum | Euphorbiaceae > Euphorbia > subg. Esula |
Sibling taxa | ||
Synonyms | Tithymalopsis exserta, E. gracilior, T. gracilis | Esula peplus, Galarhoeus peplus, Tithymalus peplus |
Name authority | (Small) Coker: Pl. Life Hartsville, 88. (1912) | Linnaeus: Sp. Pl. 1: 456. (1753) |
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