Euphorbia hyssopifolia |
Euphorbia peplidion |
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hyssopleaf sandmat |
low spurge |
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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. |
erect, unbranched or branched, 5–20 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. |
petiole 0–0.2 mm; blade linear-oblanceolate to cuneate-spatulate, 5–20 × 1–4 mm, base attenuate, margins entire, apex rounded to obtuse, surfaces glabrous; venation inconspicuously pinnate, midvein prominent. |
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. |
broadly campanulate-turbinate, 0.8–1 × 0.6–0.9 mm, glabrous; glands 4, elliptic, 0.2–0.3 × 0.5–0.6 mm; horns divergent, 0.4–0.5 mm. |
Staminate flowers | 4–15. |
5–10. |
Pistillate flowers | ovary glabrous; styles 0.5–0.9 mm, 2-fid 1/2 length. |
ovary glabrous; styles 0.5–0.7 mm, 2-fid. |
Capsules | depressed-ovoid, 1.5–1.6 × 1.7–1.8 mm, glabrous; columella 1.5–2 mm. |
depressed-globose, 1.8–2.3 × 2.6–3 mm, 3-lobed; cocci slightly flattened, without wings, smooth, glabrous; columella 1.3–1.5 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 to brown, oblong, 1.3–1.6 × 0.9–1.1 mm, abaxial faces irregularly large-pitted, adaxial faces longitudinally sulcate; caruncle flat, umbonate, 2-lobed, 0.4 × 0.7 mm. |
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. |
peduncle 0.3–0.5 mm. |
Cyathial | arrangement: terminal pleiochasial branches 3(–5), 1–3 times 2-branched; pleiochasial bracts linear, lanceolate, or spatulate, similar in size to distal leaves; dichasial bracts distinct, rhomboid-lanceolate to ovate, falcate, base rounded to obtuse, margins entire or slightly erose, apex acute; axillary cymose branches 0–3. |
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2n | = 12, 14. |
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Euphorbia hyssopifolia |
Euphorbia peplidion |
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Phenology | Flowering and fruiting late spring–early fall. | Flowering and fruiting late winter–spring. |
Habitat | Disturbed areas, ditches, gardens. | Dry, sandy areas, open areas with poor soils, roadsides, stream banks. |
Elevation | 0–1500 m. (0–4900 ft.) | 100–300 m. (300–1000 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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TX |
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 peplidion is native to central and south-central Texas. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 272. | FNA vol. 12, p. 306. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > subg. Esula |
Sibling taxa | ||
Synonyms | Chamaesyce hyssopifolia, E. jonesii, E. stenomeres | Tithymalus peplidion |
Name authority | Linnaeus: Syst. Nat. ed. 10, 2: 1048. (1759) | Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 191. (1859) |
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