Euphorbia myrsinites |
Euphorbia perennans |
|
---|---|---|
broad leaf glaucous spurge, donkey tail, myrtle or creeping or blue spurge, myrtle spurge |
perennial sandmat, Terlingua spurge |
|
Habit | Herbs, usually perennial, occasionally biennial, with taproot. | Herbs, perennial, with strongly thickened, woody rootstock. |
Stems | erect or semiprostrate, unbranched or branched, 15–40 cm, succulent, glabrous. |
erect, 7–45 cm, glabrous. |
Leaves | petiole 0–2 mm; blade obovate, obovate-oblong, lanceolate, orbiculate, or suborbiculate, 2–30 × 3–17 mm, fleshy, base truncate or attenuate, margins entire or finely denticulate, apex acute to obtuse, cuspidate or strongly mucronate, surfaces glabrous; venation and midvein inconspicuous. |
opposite; stipules distinct, linear-filiform in (1–)2(–3) segments, 0.3–0.4 mm, glabrous; petiole 0.8–2 mm, glabrous; blade ovate or orbiculate-deltate to reniform-deltate, 5–17 × 4–16 mm midstem leaves largest, base symmetric, cuneate, rounded to cordate, margins entire, apex acute to rounded, surfaces glabrous, often glaucous; 3-veined from base, only midvein conspicuous. |
Involucre | campanulate, 2.4–2.6 × 2.3–2.5 mm, glabrous; glands 4, trapezoidal, 1–1.5 × 1.5–2.5 mm; horns divergent, thick, tips rounded, dilated, 0.5–0.9 mm. |
broadly-campanulate to hemispheric, 1.7–2.2 × 1.5–2.7 mm, glabrous; glands 4, green to yellow-green, elliptic to oblong, folded longitudinally, 0.3–0.5 × 0.7–1.4 mm; appendages absent. |
Staminate flowers | 6–12. |
35–45. |
Pistillate flowers | ovary glabrous; styles 2.5–2.8 mm, usually unbranched. |
ovary glabrous; styles 0.7–0.9 mm, 2-fid nearly entire length. |
Capsules | subglobose, 5–7 × 5–6 mm, unlobed; cocci rounded to subangular, smooth, glabrous; columella 4.5–5 mm. |
subglobose to broadly ovoid, 2.8–3.3 × 2.8–3.4 mm, glabrous; columella 2.2–2.7 mm. |
Seeds | brownish to grayish, oblong, 2.8–4.5 × 2–3.2 mm, vermiculate-rugose; caruncle substipitate, trapezoidal or mushroom-shaped, 1.3–1.5 × 0.6–0.8 mm. |
white to light brown, ovoid, 3–4-angled in cross section, 2–2.4 × 1–1.2 mm, smooth to faintly transverse-wrinkled. |
Cyathial | arrangement: terminal pleiochasial branches 2–12, each 1–2 times 2-branched; pleiochasial bracts similar in shape and size to distal leaves; dichasial bracts distinct, suborbiculate or reniform, base truncate, margins entire or minutely denticulate, apex obtuse, mucronulate; axillary cymose branches 0–4. |
|
Cyathia | peduncle 0.5–1 mm. |
solitary at distal nodes or at nodes of short, axillary branches; peduncle 1.8–3 mm. |
Euphorbia myrsinites |
Euphorbia perennans |
|
Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting spring–fall. |
Habitat | Scrub oak communities, open ground near forests, shrub-steppes. | Desert scrub, on cretaceous and gypseous clay, limestone hills and flats. |
Elevation | 0–2400 m. (0–7900 ft.) | 900–1200 m. (3000–3900 ft.) |
Distribution |
CA; CO; ID; MT; NM; OR; UT; WA; WY; BC; s Europe; w Asia [Introduced in North America]
|
TX; Mexico (Chihuahua) |
Discussion | Euphorbia myrsinites is cultivated in much of the flora area, where it can tolerate cold winters. In some areas, it can locally escape from cultivation. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia perennans is a distinctive species with an erect habit and relatively large, firm, deltate midstem leaves. Phylogenetic data place E. perennans in a clade of primarily Chihuahuan Desert annual and perennial species (for example, E. chaetocalyx, E. fendleri, E. golondrina, E. simulans, E. spurca, and E. theriaca; Y. Yang and P. E. Berry 2011). Euphorbia perennans is known in the flora area only from Brewster County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 305. | FNA vol. 12, p. 282. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Tithymalus myrsinites | Chamaesyce perennans |
Name authority | Linnaeus: Sp. Pl. 1: 461. (1753) | (Shinners) Warnock & M. C. Johnston: SouthW. Naturalist 5: 170. (1960) |
Web links |
|