Euphorbia platyphyllos


Sp. Pl. 1: 460. 1753.

Common names: Broadleaf spurge
Synonyms: Galarhoeus platyphyllos (Linnaeus) Haworth Tithymalus platyphyllos (Linnaeus) Hill
Treatment appears in FNA Volume 12. Treatment on page 307. Mentioned on page 295.

Herbs, annual, with taproot. Stems erect, unbranched or branched, 15–80 cm, usually glabrous, rarely pilose. Leaves: petiole absent; blade oblanceolate or obovate, 20–50 × 5–10 mm, base subcordate or cuneate, margins finely serrulate, apex usually acute, occasionally obtuse, occasionally mucronulate, surfaces usually sparsely pilose, occasionally glabrate; venation pinnate, midvein prominent. Cyathial arrangement: terminal pleiochasial branches (3–)5, proximalmost node 3-branched, more distal ones 1–3 times 2-branched; pleiochasial bracts similar in shape and size to distal leaves; dichasial bracts distinct, ovate-triangular, base obtuse, margins finely serrulate, apex obtuse, mucronulate; axillary cymose branches 0–7(–14). Cyathia: peduncle absent. Involucre cupulate, 0.9–1.2 × 1.3–1.6 mm, sparsely pilose; glands 4, elliptic to ovate, 0.5–0.7 × 0.7–1 mm; horns absent. Staminate flowers 10–12. Pistillate flowers: ovary glabrous, styles 1.6–1.8 mm, 2-fid. Capsules globose or subglobose, 2.5–3 × 2.5–3 mm, slightly 3-lobed; cocci rounded, sparsely verrucose, glabrous; columella 1.9–2.1 mm. Seeds dark brown, ovoid, dorsiventrally compressed, 2–2.2 × 1.5–1.7 mm, smooth; caruncle ± reniform, 0.2–0.5 × 0.2–0.5 mm.

Phenology: Flowering and fruiting summer–fall.
Habitat: Lake shores, roadsides, waste places.
Elevation: 0–500 m.


V12 337-distribution-map.jpg

Introduced; Ont., Mass., Mich., N.Y., N.C., Ohio, Pa., R.I., Tenn., Vt., Wash., s Europe, introduced also in South America (Argentina, Chile, Paraguay).


Selected References


Lower Taxa

... more about "Euphorbia platyphyllos"
Ricarda Riina +, Dmitry V. Geltman +, Jess A. Peirson +  and Paul E. Berry +
Linnaeus +
Broadleaf spurge +
Ont. +, Mass. +, Mich. +, N.Y. +, N.C. +, Ohio +, Pa. +, R.I. +, Tenn. +, Vt. +, Wash. +, s Europe +, introduced also in South America (Argentina +, Chile +  and Paraguay). +
0–500 m. +
Lake shores, roadsides, waste places. +
Flowering and fruiting summer–fall. +
Weedy +  and Introduced +
Galarhoeus platyphyllos +  and Tithymalus platyphyllos +
Euphorbia platyphyllos +
Euphorbia subg. Esula +
species +