Euphorbia lurida |
Euphorbia ipecacuanhae |
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woodland spurge |
American ipecac, Carolina ipecac, ipecac spurge |
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Habit | Herbs, perennial, with thick rootstock. | Herbs, perennial, with deep, stout rootstock. |
Stems | erect or ascending, unbranched, sometimes sinuous, 5–30 cm, glabrous or sparsely to densely puberulent. |
decumbent or slightly ascending, branched, often densely clumped, previous year's dead stems not persistent, 17–27 cm, usually glabrous, rarely sparsely villous. |
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. |
alternate; stipules 0.1–0.2 mm; petiole (0–)1–2 mm, glabrous; blade usually linear, obovate, or oblanceolate to orbiculate, rarely filiform, proximal greatly reduced, scalelike, 15–70 × 1.5–13 mm gradually smaller proximally, base cuneate, margins entire, apex rounded, broadly acute, or emarginate, surfaces glabrous; venation occasionally obscure on smaller leaves, 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. |
yellow or yellow-green, hemispheric, 1–1.2 × 2–2.4 mm, glabrous; glands 5, yellow or yellow-green, obovate or elliptic, 0.7–0.8 × 1–1.2 mm; appendages white or green, often forming narrow rim around distal margin of gland, 0–0.2 mm, entire. |
Staminate flowers | 10–20. |
10–20. |
Pistillate flowers | ovary glabrous or puberulent; styles 0.7–1 mm, 2-fid. |
ovary glabrous; styles 0.4–0.8 mm, 2-fid at apex. |
Capsules | ovoid, 3.5–4 × 4–4.5 mm, 3-lobed; cocci rounded, smooth to slightly rugose, glabrous; columella 3.2–3.5 mm. |
globose, 2.3–3.4 × 3.5–4.2 mm, glabrous; columella 3–3.1 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. |
white or brown, ovoid, 2.3–2.5 × 1.5 mm, angular, with 5 longitudinal ridges, shallowly and irregularly pitted; caruncle absent. |
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. |
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Cyathia | peduncle 0.3–0.9 mm. |
usually in terminal dichasia, sometimes pleiochasia; peduncle 10–50(–70) mm, glabrous. |
Euphorbia lurida |
Euphorbia ipecacuanhae |
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Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting early spring–early summer. |
Habitat | Open pine-oak forests, dry slopes and canyons. | Pine and pine-oak savannas, pine-oak sand hills, turkey oak scrub, open sand habitats. |
Elevation | 1300–2800 m. (4300–9200 ft.) | 0–150 m. (0–500 ft.) |
Distribution |
AZ; CA; NM; NV; UT; Mexico (Baja California)
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CT; DC; DE; GA; MD; NC; NJ; NY; PA; SC; VA
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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.) |
The vegetative stems of Euphorbia ipecacuanhae are often quite short in proportion to the dichasial or pleiochasial branches, thus superficially plants often appear to have mostly opposite leaves. However, careful examination of the base of the plant will reveal alternate leaves. The leaves are extremely variable in both shape and coloration, and the variation can be pronounced within a population or even on a single plant. M. J. Huft (1979) did not recognize infraspecific taxa within E. ipecacuanhae, and his treatment is followed here. This species is found on the Atlantic coastal plain. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 305. | FNA vol. 12, p. 247. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Alectoroctonum |
Sibling taxa | ||
Synonyms | E. palmeri, E. palmeri var. subpubens, E. subpubens, Tithymalus luridus, T. palmeri, T. subpubens | E. arundelana, Tithymalopsis ipecacuanhae |
Name authority | Engelmann: in J. C. Ives, Rep. Colorado R. 4: 26. (1861) | Linnaeus: Sp. Pl. 1: 455. (1753) |
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