Euphorbia florida |
Euphorbia astyla |
|
---|---|---|
Chiricahua Mountain sandmat |
alkali spurge, Pecos spurge |
|
Habit | Herbs, annual, with slender taproot. | Herbs, perennial, with woody or fibrous-fleshy taproot, 5–12 mm thick. |
Stems | erect, 15–60 cm, usually glabrous, rarely puberulent. |
decumbent, ascending, or erect, few to many emerging from woody crown, 5–25(–50) cm, glabrous. |
Leaves | opposite; stipules distinct, divided into 3–4 subulate-filiform divisions, 0.4–1.6 mm, usually glabrous, rarely puberulent; petiole 0.5–2.5 mm, glabrous; blade usually linear, rarely to narrowly elliptic, 10–40(–60) × 0.5–2.5 mm, base symmetric, attenuate, margins serrulate, often revolute, apex acute, surfaces usually glabrous, rarely puberulent; obscurely pinnately veined. |
opposite; stipules connate into deltate scale, 0.2–0.5 mm, minutely lacerate at apex, glabrous; petiole 0–0.2(–0.3) mm, glabrous; blade orbiculate-reniform to acute-cordate, 2–5(–8) × 2–5(–6) mm, base ± asymmetric, cordate to auriculate, sometimes clasping stem, margins entire, apex narrowly acute, surfaces glabrous; 2- or 3-veined from base, but usually only midvein conspicuous. |
Involucre | obconic, 1.7–2.4 × 1.5–2.1 mm, glabrous; glands 4, greenish yellow to slightly pink, circular to oblong, 0.4–0.5 × 0.4–0.6 mm; appendages white to pink, obovoid, circular, flabellate, or oblong, 0.8–2.9 × 1–2.8 mm, distal margin entire. |
broadly campanulate, 0.8–1.4 × 0.9–1.4 mm, glabrous; glands 4, yellow-green to brownish, oblong, 0.2–0.3 × 0.5–0.7 mm; appendages white, flabellate to oblong, 0.1–0.2(–0.5) × 0.4–0.8 mm, distal margin entire or dentate-crenate. |
Staminate flowers | 25–35. |
22–26. |
Pistillate flowers | ovary glabrous; styles 0.8–1.4 mm, 2-fid entire length. |
ovary glabrous; styles 0.3–0.4 mm, unbranched, thickened-clavate. |
Capsules | oblate, 2.2–2.5 × 2.7–3.1 mm, glabrous; columella 1.8–2.1 mm. |
ovoid and broadly triangular, 1.5–1.9(–2.5) × 1.4–1.6(–2.2) mm, glabrous; columella 1.2–1.8 mm. |
Seeds | light gray to light brown, ovoid, slightly 4-angled in cross section, 1.6–2 × 1.3–1.7 mm, with 2 or 3 well-developed transverse ridges. |
white, oblong, 4-angled in cross section, adaxial faces slightly concave, with long raphe between, 1.5–1.8 × 0.7–1 mm, markedly foveolate, with irregular to ± parallel or anastomosing ridges. |
Cyathia | solitary at nodes or in small, cymose clusters at branch tips; peduncle 1.2–8.1 mm. |
solitary at distal nodes; peduncle 0.3–1(–1.5) mm. |
2n | = 28. |
|
Euphorbia florida |
Euphorbia astyla |
|
Phenology | Flowering and fruiting summer–late fall. | Flowering and fruiting late spring–early fall. |
Habitat | Sandy flats, gravelly washes, rocky hillsides, talus slopes, desert scrub, desert grasslands, mesquite woodlands, rarely oak woodlands. | Desert, grasslands, limestone substrates, usually on very saline or alkaline soils. |
Elevation | 600–1300 m. (2000–4300 ft.) | 700–1100 m. (2300–3600 ft.) |
Distribution |
AZ; Mexico (Sinaloa, Sonora)
|
TX; Mexico (Coahuila, Nuevo León) |
Discussion | Euphorbia florida is known in the flora area from Coconino County south to the Mexican border (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia astyla is a specialist on halophytic, alkaline soils and is known in the flora area only in part of Pecos County. The species is closely related to E. jejuna but differs in its sessile or sub-sessile leaves with a cordate-auriculate base and involucral gland appendages that are not deeply lobed or cleft. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 267. | FNA vol. 12, p. 261. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce florida | Chamaesyce astyla |
Name authority | Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 189. (1859) | Engelmann ex Boissier: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 15(2): 40. (1862) |
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