Euphorbia heterophylla |
Euphorbia telephioides |
|
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Mexican fireplant, painted euphorbia |
telephus spurge |
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Habit | Herbs, annual, with taproot. | Herbs, perennial, with thickened rootstock. |
Stems | erect-ascending, 20–100 cm, sparsely pilose to villous; branches ± straight. |
erect or ascending, 20–30 cm. |
Leaves | usually alternate, occasionally opposite proximally; petiole 10–50 mm, pilose; blade narrowly lanceolate to elliptic or broadly obovate (then usually pandurate and 4-lobed), often polymorphic on single plants, 30–200 × 20–140 mm, base acute, margins sparsely glandular-serrulate, hirtellous, flat, apex acute to obtuse, abaxial surface sparsely appressed-pilose, adaxial surface sparsely pilosulous to glabrate; venation pinnate, midvein prominent. |
petiole usually absent or indistinct, occasionally to 5.5 mm, blade elliptic or obovate, 31–60 × 7–32 mm, thick and fleshy, base attenuate or cuneate, apex acute, obtuse, or mucronate; venation pinnate with 8–13 lateral veins, these sometimes obscure and only midvein evident. |
Involucre | usually campanulate, occasionally nearly hemispheric, 1.5–1.9 × 1.2–1.8 mm, glabrous; involucral lobes divided into several linear, smooth lobes; gland 1, yellow-green, stipitate, clavate, 1–1.4 × 1–1.2 mm, opening circular (occasionally flattened from pressing), with annular rim, glabrous; appendages absent. |
campanulate, 1.3–2.3 × 1.6–2.5 mm, lobes ovate to oblong, 0.5–0.7 mm, ciliate; glands purple-red, oblong to trapezoidal, 0.5–0.7 × 0.8–1.2 mm, distal margins entire or crenulate. |
Staminate flowers | 8–15. |
25–30. |
Pistillate flowers | ovary glabrous or puberulent; styles 0.8–1.3 mm, 2-fid 1/2 to nearly entire length. |
gynophore exserted 1.9–3.2 mm, calyxlike lobes triangular, 0.2–0.7 mm; styles connate 1/4 length, 1.3–1.5 mm. |
Capsules | broadly ovoid, 2.8–3.8 × 4–5.3 mm, 3-lobed, usually glabrous, rarely sparsely puberulent; columella 2.1–2.8 mm. |
ovoid-oblate, 5.2–5.6 × 6.6–8.3 mm, 3-lobed; columella 3.9–4.1 mm. |
Seeds | brown-gray to ashy gray, broadly deltoid, 2.4–2.8 × 1.9–2.4 mm, angular in cross section, dorsal face strongly acute-carinate, tuberculate, with broad rounded tubercles in 2 rows; caruncle 0.1 mm. |
blackish to dark brown, ovoid to globose-ovoid, circular in cross section, 3.2–3.5 × 2.6–3.1 mm, smooth, base rounded to flattened, apex rounded, occasionally with low point. |
Cyathial | arrangement: terminal dichasial branches usually 2, occasionally reduced to congested cyme, 1–2-branched (often congested and difficult to discern); pleiochasial bracts 2–4, often whorled, wholly green or paler green at base, similar in shape and size to distal leaves; dichasial bracts highly reduced, rarely absent in highly congested clusters. |
arrangement: terminal pleiochasial branches (2–)3, 5–13 cm, 3–7 times 2-branched; pleiochasial bracts ovate to oblong, 17–31 × 8–15 mm, margins entire, apex acute or obtuse; dichasial bracts ovate, 5–19 × 3–9 mm, margins entire, apex acute or obtuse; axillary cymose branches 1–5. |
Cyathia | peduncle 0.9–1.5 mm. |
peduncle 3–9.2 mm (often exceeding subcyathial leaves). |
2n | = 28. |
|
Euphorbia heterophylla |
Euphorbia telephioides |
|
Phenology | Flowering and fruiting nearly year-round. | Flowering and fruiting spring–fall. |
Habitat | Disturbed areas, roadsides. | Scrubby pine flatwoods, grasslands, disturbed areas, often in sandy soils. |
Elevation | 0–500 m. (0–1600 ft.) | 0–20 m. (0–100 ft.) |
Distribution |
Mexico; Central America; South America [Introduced, Ala., Ariz., Calif., Fla., Ga., La., Miss., N.Mex., Tex.; introduced also in Eurasia, Africa]
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FL |
Discussion | Euphorbia heterophylla occurs from the southern United States, where it is likely naturalized, south through Mexico and Central America to South America. Because of its weediness, the precise native range in tropical and subtropical parts of the New World is not well understood. It has become widely established also in warm areas of the Old World. Leaf shape in this species is highly polymorphic within both populations and individuals. Euphorbia heterophylla can appear superficially similar to E. cyathophora but differs in its stipitate, circular involucral glands and its floral bracts that are at most very pale at the base (never colored as is typical in E. cyathophora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia telephioides, federally listed as threatened, is known only from Bay, Franklin, and Gulf counties in the Apalachicola region of the east-central Florida panhandle. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 323. | FNA vol. 12, p. 316. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Poinsettia | Euphorbiaceae > Euphorbia > sect. Nummulariopsis |
Sibling taxa | ||
Synonyms | E. geniculata, Poinsettia geniculata, P. heterophylla | Galarhoeus telephioides |
Name authority | Linnaeus: Sp. Pl. 1: 453. (1753) | Chapman: Fl. South. U.S., 402. (1860) |
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