Euphorbia eriantha |
Euphorbia hypericifolia |
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beetle spurge |
graceful sandmat, graceful spurge |
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Habit | Herbs, annual or perennial, with slender to thick, woody taproot. | Herbs, annual, with taproot. |
Stems | erect to ascending, 10–75 cm, glabrous or with scattered appressed hairs (especially near nodes); branches arcuate. |
erect to ascending, 15–50 cm, glabrous. |
Leaves | alternate; petiole 0.1–0.4 mm, often indistinct, glabrous or sparsely pilose to shortly sericeous; blade linear to linear-elliptic, 20–55 × 1–3 mm, base attenuate, margins entire or with 2–4 inconspicuous teeth near apex, apex acute, abaxial surface pilose to shortly sericeous, adaxial surface usually glabrous, rarely pilose to shortly sericeous; only midvein conspicuous. |
opposite; stipules connate, deltate, usually entire, sometimes laciniate-fringed at tip, 1.5–2.2 mm, glabrous; petiole 1–3 mm, glabrous; blade obliquely oblong-oblanceolate, 10–35 × 7–15 mm, base asymmetric, oblique, margins serrate or serrulate, especially toward apex, apex broadly acute, surfaces glabrous; palmately veined at base, pinnate distally. |
Involucre | obconic, 2.1–2.6 × 1.3–2 mm, canescent; involucral lobes triangular, obscured by hairs; glands (2–)4–5, green to maroon, color often obscured by hairs, sessile and broadly attached, 0.5–0.6 × 0.5–0.6 mm, opening oblong to nearly circular, densely canescent; appendages petaloid, whitish, hoodlike, incurved and covering glands, 0.5–1 × 0.5–0.8 mm, divided into 5–12 fringed, subulate segments, densely canescent. |
obconic, 0.9–1.1 × 0.4–0.9 mm, glabrous; glands 4, yellow-green to brown, stipitate, subcircular, 0.2 × 0.2 mm, occasionally nearly rudimentary; appendages absent on smaller glands or white to pink, shape highly variable, usually round to ± elliptic, 0.3–0.4 × 0.5–0.7 mm, distal margin entire. |
Staminate flowers | 20–25. |
(0–)2–20. |
Pistillate flowers | ovary canescent; styles 0.9–1.5 mm, unbranched. |
ovary glabrous; styles 0.4 mm, 2-fid 1/2 length. |
Capsules | oblong to ovoid, 4.4–4.9 × 3.5–4.1 mm, canescent (often with interspersed glabrescent patches); columella 3.5–3.9 mm. |
depressed-globoid, 1.3–1.4 × 1.1–1.5 mm, glabrous; columella 1–1.1 mm. |
Seeds | mottled black and gray or light brown, oblong or slightly ovoid, dorsiventrally compressed in cross section, 2.8–4.1 × 2–2.4 mm, irregularly pitted and tuberculate; caruncle 0.4–0.8 × 0.6–1.1 mm. |
with very thin whitish mucilaginous coat over light brown testa below, ovoid-triangular, bluntly 4-angled in cross section, 0.9–1.1 × 0.5 mm, with shallow irregular depressions alternating with low, smooth ridges. |
Cyathial | arrangement: terminal cymose branches 1, 1–2-branched; pleiochasial bracts 2–3, opposite or whorled, wholly green, similar in shape and size to distal leaves; dichasial bracts similar in shape to distal leaves or often highly reduced. |
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Cyathia | peduncle 1–1.9 mm. |
in dense, axillary and terminal, capitate glomerules with reduced, bractlike leaves subtending cyathia; peduncle 0.5–1.8 mm. |
Euphorbia eriantha |
Euphorbia hypericifolia |
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Phenology | Flowering and fruiting year-round in response to sufficient rainfall. | Flowering and fruiting early spring–late fall. |
Habitat | Desert scrub on rocky slopes and along washes. | Open, disturbed areas, nurseries. |
Elevation | 60–800 m. (200–2600 ft.) | 0–200 m. (0–700 ft.) |
Distribution |
AZ; CA; NM; TX; Mexico (Baja California, Baja California Sur, Chihuahua, Coahuila, Durango, San Luis Potosí, Sonora)
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AL; AR; FL; GA; LA; OK; SC; TX; Central America; South America; West Indies [Introduced in Asia, Pacific Islands]
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Discussion | Euphorbia hypericifolia is native to the New World tropics, and it is most likely adventive in the flora area (where it is most widely distributed in Florida and Texas). Reports from Arizona, California, and Maryland likely represent waifs or misidentifications. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 321. | FNA vol. 12, p. 272. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Poinsettia | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce glomerifera, C. hypericifolia, E. glomerifera | |
Name authority | Bentham: Bot. Voy. Sulphur, 51. (1844) | Linnaeus: Sp. Pl. 1: 454. (1753) |
Web links |