Euphorbia hypericifolia |
Euphorbia gracillima |
|
---|---|---|
graceful sandmat, graceful spurge |
Mexican sandmat |
|
Habit | Herbs, annual, with taproot. | Herbs, annual, with slender taproot. |
Stems | erect to ascending, 15–50 cm, glabrous. |
erect to ascending, 5–25 cm, glabrous. |
Leaves | 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. |
opposite; stipules distinct, subulate-filiform, entire, 0.3–0.5 mm, glabrous; petiole 0.4–0.9 mm, glabrous; blade narrowly oblong to linear, often slightly falcate, 2–15 × 0.3–0.8 mm, base symmetric to subsymmetric, rounded to attenuate, margins entire, thickened and often revolute, apex acute to obtuse, surfaces glabrous; only midvein conspicuous. |
Involucre | 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. |
turbinate, 0.4–0.5 × 0.4–0.6 mm, glabrous; glands 4, yellow to pink, oblong to slightly reniform, (0–)0.1–1 × 0.1–0.2 mm; appendages white to pink, ovate to oblong, 0.2–0.4 × 0.1–0.3 mm, distal margin usually entire, rarely emarginate. |
Staminate flowers | (0–)2–20. |
5–12. |
Pistillate flowers | ovary glabrous; styles 0.4 mm, 2-fid 1/2 length. |
ovary glabrous; styles 0.1–0.2 mm, 2-fid 1/2 length. |
Capsules | depressed-globoid, 1.3–1.4 × 1.1–1.5 mm, glabrous; columella 1–1.1 mm. |
broadly ovoid, 1.1–1.4 mm diam., glabrous; columella 0.8–1.1 mm. |
Seeds | 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. |
orange to tan or reddish brown, narrowly ovoid, 4-angled in cross section, 0.9–1.1 × 0.5–0.6 mm, smooth. |
Cyathia | in dense, axillary and terminal, capitate glomerules with reduced, bractlike leaves subtending cyathia; peduncle 0.5–1.8 mm. |
solitary at distal nodes; peduncle 0.1–0.9 mm. |
Euphorbia hypericifolia |
Euphorbia gracillima |
|
Phenology | Flowering and fruiting early spring–late fall. | Flowering and fruiting late summer–fall. |
Habitat | Open, disturbed areas, nurseries. | Rocky slopes and dry washes in desert scrub. |
Elevation | 0–200 m. (0–700 ft.) | 600–900 m. (2000–3000 ft.) |
Distribution |
AL; AR; FL; GA; LA; OK; SC; TX; Central America; South America; West Indies [Introduced in Asia, Pacific Islands]
|
AZ; Mexico (Chihuahua, Jalisco, Sinaloa, Sonora) |
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.) |
Euphorbia gracillima occurs from south-central Arizona (Pima and Pinal counties) south through northwestern Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 272. | FNA vol. 12, p. 270. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce glomerifera, C. hypericifolia, E. glomerifera | Chamaesyce gracillima |
Name authority | Linnaeus: Sp. Pl. 1: 454. (1753) | S. Watson: Proc. Amer. Acad. Arts 21: 438. (1886) |
Web links |