Euphorbia ophthalmica |
Euphorbia lasiocarpa |
|
---|---|---|
Florida hammock sandmat |
roadside sandmat |
|
Habit | Herbs, usually annual, rarely short-lived perennial, with slender to slightly thickened taproot. | Herbs, annual or perennial, often robust, with slender to moderately thickened taproot. |
Stems | usually prostrate, rarely ascending, 6–22 cm, usually both strigillose and hirsute. |
erect to ascending, 30–100 cm, pilose to tomentose. |
Leaves | opposite; stipules distinct, subulate-filiform, undivided or divided into 2–4 narrowly triangular to linear-subulate segments, no dark, circular glands at base of stipules, 0.9–1.5 mm, pilose or strigillose; petiole 0.3–1.2 mm, glabrescent, strigillose, or sericeous; blade usually ovate or oblong, rarely subrhombic, 4–13 × 3–7 mm, base asymmetric, one side usually angled and other side rounded, margins coarsely serrulate, apex acute, surfaces often with red spot in center, strigillose or sericeous, or adaxial surface glabrescent; 3-veined from base. |
opposite; stipules distinct when young, connate into deltate scale when older, erose to laciniate, with dark glands at margin or base, 0.5–1.3 mm, pilose; petiole 0.5–2 mm, glabrescent or pilose; blade ovate or oblong, sometimes slightly falcate, 8–46 × 3–21 mm, base asymmetric, obtuse to hemicordate, margins serrulate, apex obtuse or acute, surfaces often with red spot in center, pilose to sericeous; palmately 3–5(–7)-veined from base. |
Involucre | obconic, 0.5–0.7 × 0.4–0.6 mm, strigillose; glands 4, yellow green to pink, circular to slightly oblong, 0.1–0.2 × 0.1–0.2 mm; appendages absent or white to pink, forming thin rim around edge of gland or oblong, 0.1–0.2 × 0.1–0.3 mm, distal margin entire or shallowly lobed. |
obconic, 0.9–1.3 × 0.8–1.2 mm, pilose to sericeous; glands 4, yellow or pink, circular or oblong, 0.1–0.3 mm diam.; appendages white or pink, oblong, flabellate, or suborbiculate, 0.1–0.6 × 0.2–1 mm, entire or crenate. |
Staminate flowers | 2–8. |
15–25. |
Pistillate flowers | ovary strigillose, often canescent when young; styles 0.1–0.3 mm, 2-fid 1/2 to nearly entire length. |
ovary densely pilose to sericeous with yellowish hairs; styles 0.6–0.9 mm, 2-fid 1/2 length, filiform. |
Capsules | ovoid, 1–1.2 × 1–1.3 mm, strigillose; columella 0.7–1.1 mm. |
subglobose to broadly ovoid, 1.7–2 mm diam., pilose to sericeous with yellowish hairs; columella 1.5–1.7 mm. |
Seeds | orange-brown to pinkish, narrowly ovoid, 4-angled in cross section, 0.7–0.9(–1.1) × 0.5 mm, usually rugulose, with 3–6 faint, low, transverse ridges, rarely almost smooth. |
dark reddish brown to almost black, plumply ovoid, 4-angled in cross section, 1.2–1.3 × 0.7–0.8 mm, with 2 inconspicuous rows of 3–5 shallow depressions separated by low ridges. |
Cyathia | in dense, terminal, capitate glomerules, with reduced, bractlike leaves subtending cyathia; peduncles 0–0.8 mm. |
in dense, usually terminal, capitate glomerules, with reduced, bractlike leaves subtending cyathia; peduncle 0.8–2.3 mm. |
Euphorbia ophthalmica |
Euphorbia lasiocarpa |
|
Phenology | Flowering and fruiting year-round. | Flowering and fruiting year-round. |
Habitat | Hammock forests, disturbed areas in lawns, roadsides. | Open disturbed areas, mostly along roadsides and railroad tracks. |
Elevation | 0–200 m. (0–700 ft.) | 0–10 m. (0–0 ft.) |
Distribution |
AR; CA; FL; GA; LA; MO; PA; Mexico; Central America; South America; West Indies [Introduced in Europe] |
FL; Mexico; Central America; South America; West Indies [Introduced in North America] |
Discussion | Euphorbia ophthalmica is a weedy species distributed throughout the Neotropics. It is also adventive in the Old World. Whether it is indeed native to the southeastern United States is questionable; it is introduced in Arkansas, California, Missouri, and Pennsylvania and likely occurs also in other states. Although sometimes treated as E. hirta var. procumbens, E. ophthalmica appears sufficiently distinct to justify recognition at the rank of species, differing primarily by its mostly prostrate growth form, smaller leaves, and strictly terminal clusters of cyathia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia lasiocarpa is similar to E. hypericifolia but is much more hairy on its stems and leaves. Euphorbia lasiocarpa is widespread throughout tropical America, but its precise native range in the New World is not clear. In the flora area, E. lasiocarpa is found in southern Florida, where it is likely introduced. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 280. | FNA vol. 12, p. 275. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce ophthalmica, E. hirta var. procumbens, E. pilulifera var. procumbens | Chamaesyce lasiocarpa |
Name authority | Persoon: Syn. Pl. 2: 13. (1806) | Klotzsch: Nov. Actorum Acad. Caes. Leop.-Carol. Nat. Cur. 19(suppl. 1): 414. (1843) |
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