Euphorbia antisyphilitica |
Euphorbia mendezii |
|
---|---|---|
candelilla, wax plant |
Mendez's sandmat |
|
Habit | Shrubs, with much-branched, fleshy rootstock. | Herbs, annual or perennial, with slender taproot. |
Stems | erect, few branched, 25–50(–100) cm, glabrous or puberulent, pencil-like, in age covered with flaky, exfoliating layer of wax. |
prostrate, often mat-forming, 8–35 cm, usually villous along margins, lower surface glabrous, upper surface usually strigillose to puberulent, rarely glabrous or glabrate. |
Leaves | alternate usually caducous, sometimes persisting; stipules 0.4–0.5 mm; petiole absent; blade ovate to deltate-subulate, 2.5–4 × 1 mm, thick, fleshy, base usually rounded and swollen, rarely cuneate, margins entire, apex acute, surfaces puberulent, adaxial sometimes canescent; venation inconspicuous. |
opposite; stipules usually distinct or connate basally, rarely completely connate, deltate, laciniate, glabrous or pilose (lower side), forming narrow deltate scale, sometimes apically 2-fid or laciniate, glabrous (upper side), 0.4–1.9 mm; petiole 0.3–1.2 mm, glabrous, pilose or villous; blade oblong to obovate, 4–12 × 2–7 mm, base asymmetric, one side attenuate, cuneate or rounded, other rounded or cordate, margins serrulate at least distally, apex obtuse, surfaces glabrous or sparsely sericeous, pilose or villous; 3-veined at base. |
Involucre | campanulate, 1.6–2.2 × 1.6–1.9 mm, puberulent to canescent; glands 5, pinkish, narrowly oblong to reniform, 0.3–0.4 × 0.8–1 mm; appendages white to pink, ovate, oblong, or transversely oblong, 1.3–2.5 × 1.4–2.5 mm, usually erose, rarely entire. |
campanulate or obconic, 0.8–1 × 0.7–0.8 mm, usually glabrous, rarely sparsely pilose toward apex; glands 4, pink, reniform, oblong or elliptic, 0.1 × 0.2–0.3 mm; appendages absent or white to pink, oblong, flabellate or forming narrow rim around edge of gland, 0.1–0.3 × 0.3–0.6 mm, distal margin usually entire, sometimes lobed. |
Staminate flowers | 50–70. |
6–15. |
Pistillate flowers | ovary glabrous; styles 0.9–1.1 mm, 2-fid nearly entire length. |
ovary usually pilose or villous with hairs concentrated along keels, rarely glabrous; styles 0.2–0.3 mm, 2-fid 1/2 length. |
Capsules | oblong to ovoid, 3.9–4.2 × 3.6–3.9 mm, glabrous; columella 3.1–3.3 mm. |
ovoid, 1.2–1.6 × 1.2–1.4 mm, usually pilose or villous with hairs concentrated along keels, often glabrous in between, very rarely completely glabrous; columella 1–1.4 mm. |
Seeds | whitish gray, narrowly ovoid, 2.4–3.1 × 1.4–1.6 mm, irregularly rugose-tuberculate; caruncle crescent-shaped, 0.3–0.6 × 0.6–0.8 mm. |
reddish brown to orange or gray-pink, narrowly ovoid, 4-angled in cross section, 0.9–1.2 × 0.5–0.6 mm, almost smooth or with 5–7 faint transverse ridges that do not pass through abaxial keel. |
Cyathia | in axillary congested cymes, near branch tips or solitary at distal nodes; peduncle 0–1 mm, lanulose. |
solitary at nodes or on short, congested axillary branches; peduncle 0.9–2.5 mm. |
Euphorbia antisyphilitica |
Euphorbia mendezii |
|
Phenology | Flowering and fruiting year-round in response to sufficient rainfall. | Flowering and fruiting year-round. |
Habitat | Desert scrub, frequently on limestone substrates. | Disturbed areas. |
Elevation | 100–1200 m. (300–3900 ft.) | 0–10 m. (0–0 ft.) |
Distribution |
NM; TX; Mexico
|
FL; Mexico; Central America; West Indies; n South America [Introduced in North America] |
Discussion | Euphorbia antisyphilitica is the only pencil-stemmed species of Euphorbia occurring in the flora area. The species is characteristic of the Chihuahuan Desert scrub of Mexico from Chihuahua and Coahuila south to Hidalgo and Querétaro, and barely enters into the United States in southern New Mexico (Doña Ana and Lincoln counties) and southwest (Brewster, Hudspeth, Presidio, and Terrell counties) and south (Starr and Webb counties) Texas. The stems are covered in a conspicuous coat of exfoliating wax, and the plants historically have been harvested for this product, although the practice is much less prevalent now. The specific epithet refers to its traditional medicinal use in treating sexually transmitted infections. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia mendezii is a common weed distributed widely throughout Mexico and Central America. Within the flora area the species is known only from southern Florida. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 243. | FNA vol. 12, p. 277. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Alectoroctonum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce mendezii | |
Name authority | Zuccarini: Flora 15(2, Beibl.): 58. (1832) | Boissier: Cent. Euphorb., 15. (1860) |
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