Euphorbia parryi |
Euphorbia indivisa |
|
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dune spurge, Parry's sandmat, Parry's spurge |
royal sandmat |
|
Habit | Herbs, annual, with taproot. | Herbs, annual or short-lived perennial, with slender taproot to thickened and woody rootstock. |
Stems | usually prostrate, rarely ascending-erect, 5–70(–85) cm, glabrous. |
prostrate, usually mat-forming, terete to slightly flattened, 40 cm, lower surface glabrous, upper surface strigillose, pilose or villous. |
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, entire or divided into 3–4 subulate to filiform segments, 0.8–2 mm, usually pilose, rarely glabrous; petiole 0.5–1 mm, pilose to villous; blade oblong, ovate or narrowly obovate, 3–10(–12) × 2–6 mm, base strongly asymmetric, hemicordate, margins serrulate, apex obtuse to subacute, surfaces glabrous or slightly pilose; 3-veined from base, often 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. |
narrowly turbinate, 1–1.2 × 0.4–0.7 mm, pilose; glands 4, yellow to pink, unequal, proximal pair oblong or linear, 0.1 × 0.3–0.4(–0.6) mm, distal pair oblong or subcircular, 0.1 × 0.1–0.2 mm; appendages pink to reddish, unequal, on proximal glands oblique, 0.4–0.8(–1) × 0.8–1.4(–2) mm, on distal glands symmetric, 0.2–0.5 × 0.2–0.5 mm, slightly undulate to slightly crenate. |
Staminate flowers | 40–55. |
5–15. |
Pistillate flowers | ovary glabrous; styles 0.5–0.7 mm, 2-fid nearly entire length. |
ovary pilose to strigillose in parts, glabrous in other parts; styles 0.8–1.3 mm, usually unbranched, rarely 2-fid at apex, filiform. |
Capsules | ovoid-globose, 2–2.3 × 1.5–2.5 mm, glabrous; columella 1.4–2 mm. |
ovoid-triangular, 1.2–1.5 × 1–1.4 mm, pilose to strigillose in parts, glabrous in other parts; columella 1–1.3 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. |
brown to light gray, ovoid, 4-angled in cross section, 0.8–1 × 0.4–0.5 mm, with 4 or 5 deep transverse sulci alternating with low transverse ridges. |
Cyathia | solitary or in small clusters on short axillary branches at distal nodes; peduncle 1–5 mm. |
usually in small cymose clusters on congested, axillary branches; peduncle rudimentary or to 0.2 mm. |
Euphorbia parryi |
Euphorbia indivisa |
|
Phenology | Flowering and fruiting spring–fall. | Flowering and fruiting summer–fall. |
Habitat | Sand dunes, other sandy habitats. | Grasslands, oak forests, oak-mesquite woodlands, oak-juniper communities, rarely entering desert scrub. |
Elevation | 200–2200 m. (700–7200 ft.) | 1000–2000 m. (3300–6600 ft.) |
Distribution |
AZ; CA; CO; NM; NV; TX; UT; Mexico (Chihuahua)
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AZ; NM; TX; Mexico
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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 indivisa is characteristic of grasslands and oak woodlands from extreme western Texas to southeastern Arizona. The species is often treated as a synonym of E. dioeca Kunth, but the two species are readily separable on the basis of their seeds. The seeds of E. indivisa possess deep transverse sulci, whereas those of E. dioeca are merely rippled or with low transverse ridges. Euphorbia dioeca is a weedy species that occurs widely throughout tropical America but has yet to be encountered within the flora area. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 281. | FNA vol. 12, p. 273. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce longeramosa, C. parryi, E. longeramosa | E. dioeca var. indivisa, Chamaesyce indivisa |
Name authority | Engelmann: Amer. Naturalist 9: 350. (1875) | (Engelmann) Tidestrom: Proc. Biol. Soc. Wash. 48: 40. (1935) |
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