Euphorbia terracina |
Euphorbia tetrapora |
|
---|---|---|
carnation spurge, Geraldton carnation weed, terracina spurge |
weak spurge |
|
Habit | Herbs, perennial or biennial, with taproot. | Herbs, annual, with taproot. |
Stems | erect, unbranched or branched, 10–100 cm, glabrous. |
erect, unbranched, 7–20 cm, glabrous. |
Leaves | petiole absent; blade linear, linear-lanceolate, oblong-elliptic, or obovate, 4–50 × 2–10 mm, base obtuse or truncate, margins finely serrulate, apex acute, obtuse, or truncate, sometimes mucronulate, surfaces glabrous; venation inconspicuous, only midvein prominent. |
petiole 1–2 mm, reduced distally; blade spatulate-cuneate, 8–10 × 4–5 mm (greatly reduced in size proximally), base cuneate, margins entire, apex rounded to emarginate or obcordate, surfaces glabrous; venation pinnate. |
Involucre | cupulate to slightly turbinate, 1.1–2 × 1.3–1.5 mm, glabrous or puberulent; glands 4, elliptic to trapezoidal, 0.6–0.8 × 1–2 mm; horns slightly convergent to divergent, 1–2 mm. |
campanulate, 0.8–1.1 × 0.7–1 mm, glabrous; glands 4, elliptic to trapezoidal, 0.3–0.6 × 0.6–1.2 mm; horns divergent, 0.5–1 mm. |
Staminate flowers | 15–20. |
10–15. |
Pistillate flowers | ovary glabrous; styles 1–1.8 mm, 2-fid. |
ovary smooth, glabrous; styles 0.6–1 mm, 2-fid. |
Capsules | depressed-globose, 2.5–3 × 3–4.5 mm, deeply 3-lobed; cocci rounded to subangular, smooth, glabrous; columella 1.9–2.3 mm. |
depressed-globose, 1.8–2.2 × 2.2–2.9 mm, slightly lobed; cocci rounded to slightly flattened, smooth, glabrous; columella 1.5–1.8 mm. |
Seeds | pale gray, subovoid, 1.6–2.4 × 1.3–1.8 mm, smooth; caruncle boat-shaped, 0.4–0.6 × 0.4–0.6 mm. |
reddish brown to brown, often glaucous, oblong, 1.3–1.4 × 0.8–0.9 mm, abaxial faces with 15–20 shallow pits or almost smooth, adaxial faces with 4–6 large shallow pits or irregular oblong grooves; caruncle conic, hat-shaped, 0.3–0.4 × 0.4–0.6 mm. |
Cyathial | arrangement: terminal pleiochasial branches 2–5, each 1–5 times 2-branched; pleiochasial bracts lanceolate, elliptic or ovate, similar in size to distal leaves; dichasial bracts distinct, ovate to subreniform, base cuneate to cordate, margins finely serrulate, apex acute, obtuse, or rounded, sometimes mucronulate or cuspidate; axillary cymose branches 0–7. |
arrangement: terminal pleiochasial branches 3, each 1–3(–4) times 2-branched; pleiochasial bracts obovate, similar in size to distal leaves; dichasial bracts distinct or basally subconnate, not imbricate, triangular-ovate, base truncate or cordate, margins entire, apex mucronate; axillary cymose branches 1–4. |
Cyathia | peduncle 1–3 mm. |
peduncle 0.2–0.6 mm. |
Euphorbia terracina |
Euphorbia tetrapora |
|
Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting spring. |
Habitat | Edges of cultivated fields and woodlands, roadsides, waste areas, pastures, coastal bluffs, dunes, riparian areas. | Sandy soils, dry open woods. |
Elevation | 0–300 m. (0–1000 ft.) | 0–300 m. (0–1000 ft.) |
Distribution |
CA; Europe [Introduced in North America; introduced also in Mexico, s Africa, Australia]
|
LA; OK; TX |
Discussion | Euphorbia terracina is native to the Mediterranean region of Europe. This species is invasive and spreading rapidly, displacing native coastal scrub in southern California, and has been listed as a noxious weed by that state. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia tetrapora is endemic to a portion of the western Gulf coastal plain. D. S. Correll and M. C. Johnston (1970) included Alabama and Georgia in the distribution of this species as well, probably due to Engelmann’s citation of a Georgia specimen from the herbarium of Samuel Boykin. Whether the Boykin specimen came from Georgia, where Boykin was based, is unclear. Because no records to support its occurrence in the eastern Gulf coastal plain (Alabama or Georgia) have been found, those states are here excluded from the distribution of E. tetrapora. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 310. | FNA vol. 12, p. 311. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > subg. Esula |
Sibling taxa | ||
Synonyms | Tithymalus terracinus | Tithymalus tetraporus |
Name authority | Linnaeus: Sp. Pl. ed. 2, 1: 654. (1762) | Engelmann: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 191. (1859) |
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