Euphorbia abramsiana |
Euphorbia garberi |
|
---|---|---|
Abrams' sandmat, Abrams' spurge |
Garber's sandmat |
|
Habit | Herbs, annual, with slender taproot. | Herbs, perennial, with moderately thickened rootstock. |
Stems | prostrate, mat-forming, 10–35(–50) cm, shortly pilose or puberulent at least proximally, often glabrous distally. |
ascending, sometimes slightly woody at base, not wiry, 1–3 mm diam., 15–50 cm, canescent. |
Leaves | opposite; stipules distinct, divided into 5–7 subulate-filiform segments, 0.6–1.1 mm, usually glabrous, rarely pilose; petiole 0.5–1 mm, glabrous; blade ovate, elliptic-oblong, or slightly ovate-cordate, 3–11 × 2–5 mm, base asymmetric, truncate to hemicordate, margins serrulate at least toward apex, often entire toward base, apex acute to obtuse, surfaces sometimes with red spot in center, glabrous; usually only the midvein conspicuous. |
opposite; stipules distinct or connate at base, triangular-subulate, apex divided into 2–5 subulate to subulate-filiform segments, 0.5–0.7 mm, pilose; petiole 0.5–1.1 mm, pilose; blade ovate to oblong-elliptic, 4–9(–15) × 3–6 mm, base asymmetric, obtuse to rounded, margins usually entire, rarely very sparsely serrulate, apex usually obtuse to rounded, occasionally acute to apiculate, surfaces canescent; 3-veined from base, only midvein conspicuous. |
Involucre | obconic, 0.5–0.6 × 0.4–0.5 mm, glabrous; glands 4, yellowish to pink, circular to oblong, 0.1 × 0.1–0.2 mm; appendages absent, or white to pink, semicircular to broadly ovate, to 0.1 × 0.2 mm, distal margin entire or shallowly lobed. |
turbinate to campanulate, 0.6–0.9 × 0.5–0.9 mm, pilose; glands 4, brown, slightly concave, elliptic to subcircular, 0.1–0.3 × 0.2–0.4 mm; appendages white to pink, as narrow rim along gland, (0–)0.1–0.2 × 0.3–0.5 mm, surfaces pilose, distal margin entire or crenulate. |
Staminate flowers | 3–5. |
8–20. |
Pistillate flowers | ovary glabrous; styles 0.1–0.3 mm, 2-fid nearly entire length. |
ovary pilose; styles 0.6–0.7 mm, 2-fid 1/2 length. |
Capsules | ellipsoid to ovoid, 1.3–1.5 × 1.1–1.5 mm, glabrous; columella 1–1.3 mm. |
subglobose to broadly ovoid, 1.1–1.6 × 1.3–2.1 mm, pilose; columella 1.1–1.6 mm. |
Seeds | light gray to light brown, narrowly ovoid to ovoid, 4-angled in cross section, 1–1.2 × 0.6–0.7 mm, with 3–5 prominent transverse ridges that often interrupt abaxial keel. |
gray to reddish brown, oblong-ovoid, 4-angled in cross section, 1–1.2 × 0.6–0.8 mm, flat or obscurely wrinkled. |
Cyathia | solitary at distal nodes of primary stems or at nodes of short congested axillary branchlets; peduncle 0.2–0.5 mm. |
solitary at nodes of short, axillary branches; peduncle 0.2–0.4 mm. |
Euphorbia abramsiana |
Euphorbia garberi |
|
Phenology | Flowering and fruiting summer–fall. | Flowering and fruiting year-round. |
Habitat | Desert scrub and desert grasslands. | Beach dunes, coastal rock barrens, disturbed uplands and pine rocklands. |
Elevation | -40–1400 m. (-100–4600 ft.) | 0–10 m. (0–0 ft.) |
Distribution |
AZ; CA; NM; TX; Mexico (Baja California, Baja California Sur, Sonora)
|
FL |
Discussion | Euphorbia garberi appears to be an interspecific hybrid, but its parentage is not entirely clear (Y. Yang and P. E. Berry 2011). The taxon is closely related to E. blodgettii, E. porteriana, and E. serpens. It is restricted to Collier, Miami-Dade, and Monroe counties in southern Florida and is federally listed as threatened due to impacts from habitat loss, fire suppression, and invasive species. A. Herndon (1993) synonymized E. porteriana var. keyensis under E. garberi because of its uniformly pilose capsules, and that treatment is followed here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 12, p. 259. | FNA vol. 12, p. 268. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce abramsiana | Chamaesyce adicioides, C. brachypoda, C. garberi, C. keyensis, C. mosieri, C. porteriana var. keyensis, E. porteriana var. keyensis |
Name authority | L. C. Wheeler: Bull. S. Calif. Acad. Sci. 33: 109. (1934) | Engelmann ex Chapman: Fl. South. U.S. ed. 2, 646. (1883) |
Web links |