Euphorbia parryi |
Euphorbia arizonica |
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dune spurge, Parry's sandmat, Parry's spurge |
Arizona sandmat, Arizona spurge |
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Habit | Herbs, annual, with taproot. | Herbs, annual or short-lived perennial, with slender to slightly thickened taproot. |
Stems | usually prostrate, rarely ascending-erect, 5–70(–85) cm, glabrous. |
erect to ascending, 10–30 cm, uniformly pilose with glistening hairs. |
Leaves | opposite; stipules distinct, linear-subulate, usually lacerate and divided into 2 or more slender segments, rarely entire, 0.6–1.4 mm, glabrous; petiole 1–2.5 mm, glabrous; blade linear to narrowly oblong, (5–)10–25(–30) × 2–5 mm, base usually symmetric, sometimes slightly asymmetric, attenuate, margins entire, occasionally ± revolute, apex acute to obtuse, mucronulate, surfaces glabrous; only midvein conspicuous. |
opposite; stipules distinct, deltate, (0–)0.1 mm, glabrous or with few scattered hairs; petiole 0.4–1.5 mm, pilose with glistening hairs; blade usually ovate, rarely elliptic, 3–11 × 2–7 mm, base asymmetric, one side cuneate to rounded, other side rounded to strongly cordate, margins entire, apex obtuse or acute, surfaces pilose with glistening hairs; 3-veined from base but usually only midvein conspicuous. |
Involucre | broadly cupuliform-campanulate, 1.2–1.7 × 1.4–1.8 mm, glabrous; glands 4, reddish pink to greenish yellow, deeply concave, elliptic to oblong, 0.2–0.3 × 0.3–0.5 mm; appendages white, elliptic to oblong, usually forming narrow margin around gland, sometimes rudimentary, 0.2–0.6 × 0.3–0.7(–1.1) mm, distal margin entire. |
urceolate, 1.1–1.3 × 0.5–0.9 mm, glabrous or pilose with glistening hairs; glands 4, dark maroon, usually oblong to reniform, rarely almost circular, 0.2 × 0.2–0.4 mm; appendages white to pink, oblong, flabellate, oblong, or elliptic, 0.3–0.6 × 0.6–0.9 mm, distal margin entire or crenulate. |
Staminate flowers | 40–55. |
5–12. |
Pistillate flowers | ovary glabrous; styles 0.5–0.7 mm, 2-fid nearly entire length. |
ovary pilose, styles 0.5–0.6 mm, 2-fid 1/2 length. |
Capsules | ovoid-globose, 2–2.3 × 1.5–2.5 mm, glabrous; columella 1.4–2 mm. |
broadly ovoid to subglobose, 1.4–1.8 mm diam., pilose; columella 1.1–1.4 mm. |
Seeds | mottled brown and white because of irregularly loose and tight outer covering, broadly ovoid, rounded-angular in cross section, 1.4–1.8 × 0.8–1 mm, smooth or only inconspicuously roughened. |
gray to light brown, ovoid, 4-angled in cross section, 0.9–1.1 × 0.5–0.6 mm, rugose with 2–5 irregular transverse ridges that sometimes pass through abaxial keel. |
Cyathia | solitary or in small clusters on short axillary branches at distal nodes; peduncle 1–5 mm. |
solitary at distal nodes; peduncle 0.7–3.6 mm. |
Euphorbia parryi |
Euphorbia arizonica |
|
Phenology | Flowering and fruiting spring–fall. | Flowering and fruiting year-round in response to sufficient moisture. |
Habitat | Sand dunes, other sandy habitats. | Washes and rocky slopes, sometimes on limestone, desert scrub communities often with creosote-bush, riparian forests, mesquite woodlands, oak chaparral. |
Elevation | 200–2200 m. (700–7200 ft.) | 100–1400 m. (300–4600 ft.) |
Distribution |
AZ; CA; CO; NM; NV; TX; UT; Mexico (Chihuahua)
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AZ; CA; NM; TX; Mexico (Baja California, Baja California Sur, Chihuahua, Coahuila, Durango, Sonora)
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Discussion | Euphorbia parryi is similar to E. missurica, differing only by the generally narrow involucral gland appendages and prostrate habit in E. parryi as opposed to the conspicuous involucral gland appendages and ascending-erect habit in E. missurica. Euphorbia parryi has sometimes been considered the western race of E. missurica (D. S. Correll and M. C. Johnston 1970). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia arizonica is distinctive and easily recognized by its glistening, translucent hairs that appear somewhat glutinous and are most apparent on the stems. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 281. | FNA vol. 12, p. 260. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce longeramosa, C. parryi, E. longeramosa | Chamaesyce arizonica |
Name authority | Engelmann: Amer. Naturalist 9: 350. (1875) | Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 186. (1859) |
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