Euphorbia hexagona |
Euphorbia pinetorum |
|
---|---|---|
six-angle spurge |
pineland spurge |
|
Habit | Herbs, annual, with taproot. | Herbs, perennial, with thickened, woody taproot. |
Stems | erect, unbranched or branched, 30–70(–100) cm, sparsely hispid, occasionally densely so at distal nodes. |
erect, 30–100 cm, glabrous; branches ± straight. |
Leaves | opposite; stipules (0–)0.1 mm; petiole 1–4 mm, pilose; blade linear-filiform, linear, or elliptic, 21–40 × 0.9–7.5 mm, base attenuate, margins entire, apex acute, abaxial surface sparsely hispidulous to strigillose, adaxial surface glabrous; venation obscure, only midvein conspicuous. |
usually alternate, occasionally opposite proximally; petiole 0–1.5 mm, glabrous; blade narrowly lanceolate to linear, base long-attenuate, 30–120 × 2.5–5 mm, margins usually entire, occasionally with few inconspicuous teeth, revolute, apex narrowly acute, surfaces glabrous; venation obscurely pinnate, midvein prominent. |
Involucre | campanulate, 1–1.5 × (1–)1.5–1.8 mm, hispid; glands 5, green to deep red, elliptic to reniform, 0.5 × 0.8–1 mm; appendages white to green, tinged red, deltate to ovate, 0.7–1.7 × (0.9–)1.3–1.5 mm, entire. |
campanulate, 1.5–1.9 × 1.4–1.7 mm, glabrous; involucral lobes divided into broad, triangular segments; glands 3(–5), red to purple, sessile and broadly attached, 0.8–1.1 × 1.2–1.6 mm, opening oblong (flattened without pressing), without annular rim, glabrous; appendages absent. |
Staminate flowers | 15–30(–40). |
8–12. |
Pistillate flowers | ovary glabrous; styles 0.7–1.1 mm, 2-fid nearly entire length. |
ovary glabrous; styles 1.5 mm, 2-fid nearly entire length. |
Capsules | subglobose to broadly ovoid, 4.7–6.5 × 4.9–6.5(–7.1) mm, glabrous; columella 3.5–4.5 mm. |
purpurescent, depressed-globose, 2.8–3.2 × 3.6–4 mm, 3-lobed, glabrous; columella 2.6–2.9 mm. |
Seeds | dark brown or dark gray, ovoid, 3.4 × 2.7 mm, rugose, whitish glaucous; caruncle absent. |
dark brown, cylindric-ovoid to ovoid, rounded in cross section, 2.1–2.4 × 2 mm, uniformly low-tuberculate, tubercles in median, transverse ridge; caruncle absent. |
Cyathia | solitary in leaf axils or in terminal cymes or dichasia; peduncle 1–2.1 mm, strigillose. |
peduncle 1.5–3 mm. |
Cyathial | arrangement: terminal monochasial or dichasial branches 1–2, unbranched; pleiochasial bracts 2–3, often whorled, wholly purpurescent green or pink at base, similar in shape and size to distal leaves or slightly narrower; dichasial bracts highly reduced. |
|
Euphorbia hexagona |
Euphorbia pinetorum |
|
Phenology | Flowering and fruiting late summer–fall. | Flowering and fruiting year-round. |
Habitat | Sand prairies, other sandy soil habitats, stream banks, sand bars, damp places. | Sandy soils in pinelands. |
Elevation | 200–1300 m. (700–4300 ft.) | 0–10 m. (0–0 ft.) |
Distribution |
AR; CO; IA; IL; KS; MN; MO; MT; NE; NM; OK; SD; TX; WI; WY
|
FL |
Discussion | Euphorbia hexagona is native to the central United States and is most common from southern South Dakota to Oklahoma and northern Texas. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia pinetorum has a restricted distribution in southern peninsular Florida, primarily in Miami-Dade and Monroe counties. The species is very similar to narrow-leaved forms of the closely related E. cyathophora but differs in its perennial habit, consistently unlobed leaves, and purpurescent involucral glands and cyathia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 247. | FNA vol. 12, p. 323. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Alectoroctonum | Euphorbiaceae > Euphorbia > sect. Poinsettia |
Sibling taxa | ||
Synonyms | Poinsettia pinetorum | |
Name authority | Nuttall ex Sprengel: Syst. Veg. 3: 791. (1826) | (Small) G. L. Webster: J. Arnold Arbor. 48: 403. (1967) |
Web links |