Euphorbia polycarpa |
Euphorbia nutans |
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smallseed sandmat |
eyebane, eyebane sandmat, eyebane spurge, nodding or upright spotted spurge, nodding spurge |
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Habit | Herbs, annual, with taproot. | |
Stems | usually ascending, occasionally erect, often arched at tips, 20–80 cm, sparsely to moderately pilose to villous or with short, incurved hairs, hairs often concentrated at nodes and distally, occasionally in 2 bands along opposite sides of stem. |
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Leaves | opposite; stipules usually distinct, sometimes connate basally on one side of stem, small scales, irregularly toothed, fringed, or divided, 1–1.5 mm, sparsely to moderately villous distally; petiole 0.3–1.6 mm, moderately pilose to villous; blade oblong to oblong-lanceolate, 8–40 × 3–12 mm, base asymmetric, one side usually angled or rounded, other side ± truncate to cordate-auriculate, margins serrulate, apex angled with blunt tip, abaxial surface pale green or faintly to strongly reddish tinged, adaxial surface usually reddish-mottled or with conspicuous reddish spot, both surfaces usually sparsely to moderately pilose, especially toward base, sometimes glabrous; 3–5-veined from base, pinnate distally, veins faint. |
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Involucre | narrowly obconic, 0.5–1 × 0.3–0.7 mm, glabrous; glands 4, usually green, sometimes reddish purple, oblong to nearly circular, 0.2–0.4 × 0.3–0.5 mm; appendages white or pinkish, ovate to broadly elliptic, 0.2–1 × 0.2–1.5 mm, distal margin entire. |
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Staminate flowers | 5–28. |
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Pistillate flowers | ovary glabrous; styles 0.6–2.5 mm, 2-fid 1/2 length. |
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Capsules | ovoid, 1.6–2.3 × 1.5–2.4 mm, glabrous; columella 1.4–1.6 mm. |
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Seeds | dark brown, sometimes with thin, white coating (often more persistent along angles than faces), elliptic-ovoid to ovoid, rounded-angular in cross section, 1–1.6 × 0.5–0.8 mm, surface finely and irregularly wrinkled, sometimes faintly so, or with indistinct, shallow, rounded cross ridges. |
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Euphorbia | polycarpa is a highly variable species distributed throughout the Baja California peninsula, eastern Sonora, and the arid southwestern United States from southwestern Arizona to southern Nevada and central California. |
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l | . |
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c | . |
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Wheeler | (1941) divided the species into seven varieties, the majority of which occur in Baja California Sur. |
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He | reported two of these for the United States: var. hirtella and var. polycarpa. |
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Variety | hirtella, as the name suggests, was applied to hairy plants. |
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However | , it is here treated as a synonym of var. polycarpa, because variation in pubescence shows no geographic segregation and ranges along a continuum from glabrous or sparsely to densely hairy, and because glabrous and hairy branches can occur on the same individual. |
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Cyathia | solitary at distal nodes or in small, cymose clusters at branch tips; peduncle 0.5–2.5 mm. |
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2n | = 12, 14, 22. |
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Euphorbia polycarpa |
Euphorbia nutans |
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Phenology | Flowering and fruiting spring–early fall. | |
Habitat | Stream banks, pond edges, disturbed portions of upland prairies, mesic to dry upland forest openings, pastures, fallow fields, railroads, roadsides, gardens, disturbed areas. | |
Elevation | 0–1600 m. (0–5200 ft.) | |
Distribution |
AZ; CA; NV; nw Mexico
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AL; AR; CA; CT; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; MI; MN; MO; MS; NC; ND; NE; NH; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; WY; ON; QC; Mexico; Central America; South America; West Indies [Introduced in Eurasia]
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Discussion | Varieties 5 (1 in the flora). Some of the varieties occurring in Mexico are highly divergent and appear to be sufficiently distinct to merit recognition as species. However, within the flora area, Euphorbia polycarpa is relatively uniform, and the only noteworthy variation involves the size of the involucral gland appendages. In the portion of the California Floristic Province occupied by E. polycarpa (Los Angeles, Orange, western Riverside, western San Diego, and Ventura counties) the appendages are conspicuously larger than those of plants throughout the remainder of its range in the southwestern United States (0.4–1.2 versus 0.1–0.3 mm). Large-appendaged plants are also common in Baja California and correspond well with the type collection. The taxonomic significance of this variation is not clear at this time, and the small-appendaged plants may merit segregation as an infraspecific taxon. However, no formal changes are proposed, awaiting a comprehensive review of the species throughout its range. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia nutans is probably native to at least central and eastern North America, but given its strongly weedy tendencies, it is difficult to know where it may be adventive in parts of the flora area. It is certainly introduced where it occurs in the Old World and probably in South America as well. D. G. Burch (1966) discussed the problems of assigning names to the four main entities in this nomenclatural complex (E. hypericifolia, E. hyssopifolia, E. lasiocarpa, and E. nutans) and determined that the oldest valid name for the relatively robust, temperate North American plants with ascending stems is E. nutans. See the treatment of 56. E. maculata for a discussion of the misapplication of that name to E. nutans. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 283. | FNA vol. 12, p. 278. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Subordinate taxa | ||
Synonyms | Chamaesyce polycarpa | Chamaesyce lansingii, C. nutans, E. lansingii, E. preslii |
Name authority | Bentham: Bot. Voy. Sulphur, 50. (1844) | Lagasca: Gen. Sp. Pl., 17. (1816) |
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