Euphorbia hyssopifolia |
Euphorbia cordifolia |
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hyssopleaf sandmat |
heartleaf sandmat |
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Habit | Herbs, annual, with taproot. | Herbs, annual, with taproot. |
Stems | erect to ascending, 80 cm, sparsely to densely pilose or pilose-crinkled proximally, usually glabrous distally. |
prostrate, occasionally mat-forming, 10–43 cm, glabrous. |
Leaves | opposite; stipules usually connate, irregularly lacerate, 0.5–1 mm, usually glabrous, occasionally with few marginal hairs; petiole 1–2 mm, glabrous; blade lanceolate to oblong or falcate, 8–35 × 7–15 mm, base asymmetric, rounded, margins serrulate, apex broadly acute, abaxial surface glabrous or sparsely pilose toward base, adaxial surface glabrous; palmately veined at base, pinnate distally. |
opposite; stipules usually distinct, occasionally connate at base, filiform, 1–1.2(–2.8) mm, usually glabrous, rarely pilose; petiole 0.4–1 mm, usually glabrous; blade ovate to oblong, 4.4–12 × 2.6–7.6 mm, base asymmetric, cordate to rounded, margins entire, apex rounded to mucronulate, surfaces glabrous; only midvein conspicuous. |
Involucre | obconic, 0.9–1.1 × 0.7–0.9 mm, glabrous; glands 4(–5) (5th gland without appendage), yellow-green to maroon, elliptic to circular, 0.1–0.2 × 0.1–0.3 mm; appendages spreading, usually white or turning reddish with age, short reniform or semilunate, 0.1–0.3 × 0.2–0.6 mm, distal margin entire or slightly undulate to crenate. |
campanulate, 1–1.3 × 1–1.3 mm, glabrous; glands 4, yellowish to pink, elliptic, 0.3–0.5 × 0.5–1 mm; appendages whitish to pink, sometimes drying red, elliptic to ovoid, 1.1–1.5 × 1.2–1.9 mm, distal margin entire, retuse, or erose. |
Staminate flowers | 4–15. |
5–40. |
Pistillate flowers | ovary glabrous; styles 0.5–0.9 mm, 2-fid 1/2 length. |
ovary glabrous; styles 0.5–0.8 mm, 2-fid nearly entire length. |
Capsules | depressed-ovoid, 1.5–1.6 × 1.7–1.8 mm, glabrous; columella 1.5–2 mm. |
ovoid, 2–3 mm diam., glabrous; columella 1.2–2.7 mm. |
Seeds | brown to grayish white, ovoid, slightly 4-angled in cross section, abaxial faces convex, adaxial faces slightly concave to slightly convex, 1–1.4 × 0.7–1.1 mm, with 2–3 prominent transverse ridges that do not interrupt adaxial keel, or coarsely and inconspicuously pitted-reticulate. |
gray or tan with dark brown mottling, ovoid, bluntly 3–4-angled in cross section, 1.8–2.1 × 1.2–1.4 mm, smooth to rugose. |
Cyathia | solitary or in small, cymose clusters occasionally with bractlike leaves at distal nodes or on congested, axillary branches; peduncle 0.5–2.5 mm. |
solitary at distal nodes; peduncle 0.9–3 mm. |
2n | = 12, 14. |
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Euphorbia hyssopifolia |
Euphorbia cordifolia |
|
Phenology | Flowering and fruiting late spring–early fall. | Flowering and fruiting summer–fall. |
Habitat | Disturbed areas, ditches, gardens. | Xeric oak-pine scrub, pine-barrens, sand barrens, sandy stream banks. |
Elevation | 0–1500 m. (0–4900 ft.) | 0–200 m. (0–700 ft.) |
Distribution |
AL; AZ; FL; GA; LA; MS; NM; SC; TX; UT; Mexico; Central America; South America; West Indies [Introduced in tropical Asia, Africa, Australia]
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AL; AR; FL; GA; LA; MS; NC; OK; SC; TX
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Discussion | Euphorbia hyssopifolia is native to the New World tropics and is probably also native to parts of the southern United States. However, at least some of the records from the flora area appear to be from adventive plants. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia cordifolia is easily identified by its cordate to rounded leaf base and distinctive filiform stipules. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 272. | FNA vol. 12, p. 265. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce hyssopifolia, E. jonesii, E. stenomeres | Chamaesyce cordifolia |
Name authority | Linnaeus: Syst. Nat. ed. 10, 2: 1048. (1759) | Elliott: Sketch. Bot. S. Carolina 2: 656. (1824) |
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