Boerhavia diffusa |
Boerhavia triquetra |
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red spiderling, spreading hogweed |
creeping sticky stem, slender spiderling |
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Habit | Herbs, perennial [rarely appearing annual], sometimes slightly woody at base; taproot fusiform, woody. | Herbs, annual; taproot tapered, soft or ± woody. |
Stems | decumbent, ascending, or erect, usually profusely branched throughout, 3–10 dm, glabrous or minutely pubescent basally, glabrous or sparsely pubescent distally. |
erect or ascending, occasionally decumbent, moderately or profusely branched, primarily distally, 1–5 dm, minutely puberulent with bent hairs basally, glabrous or minutely puberulent distally. |
Leaves | mostly in basal 1/2 of plant; larger leaves with petiole 10–30 mm, blade broadly lanceolate, ovate, or broadly ovate, occasionally ± round, 20–60 × 15–50 mm (distal leaves smaller, often proportionally narrower), base truncate, broadly cuneate, round, or shallowly cordate, often oblique, margins sinuate, apex obtuse to round, abaxial surface paler than adaxial, glabrous or minutely puberulent, sometimes glandular, usually with few large multicellular hairs on veins, adaxial surface glabrous, rarely sparsely puberulent, neither surface punctate. |
mostly in basal 1/2 of plant; larger leaves with petiole 4–8[–15] mm, blade broadly ovate or oval to lanceolate, 10–21[–35] × 6–8[–13] mm (distal leaves smaller, proportionately narrower), adaxial surface usually glabrous, rarely minutely puberulent, abaxial surface paler than adaxial, glabrous, neither surface punctate, base round [obtuse], margins shallowly sinuate, apex acute, obtuse, or round. |
Inflorescences | terminal, forked ca. 3–6 times ± equally, diffuse, occasionally with sticky internodal bands; branches divergent, terminating in compact subumbellate or capitate, 2–5-flowered clusters. |
terminal or axillary, forked ca. 3–6 times ± evenly (or clearly unevenly), diffuse, with sticky internodal bands; branches usually terminating in umbels or flowers borne singly, usually well beyond leaves. |
Flowers | pedicel shorter than 0.5 mm; bract at base of perianth quickly deciduous, 1, lanceolate, 0.8–1 mm; perianth purplish red to reddish pink or nearly white, campanulate beyond constriction, 1–1.5 mm; stamens 2–3, included or barely exserted. |
pedicel 0.3–4.5 mm; bracts at base of perianth quickly deciduous, 2, linear-lanceolate to lanceolate [ovate], 0.5–0.6 mm; perianth whitish to pale pink or purplish, campanulate beyond constriction, 1 mm; stamens 2–3, included or barely exserted. |
Fruits | (1–)2–5(–9) per cluster, gray-brown to brown, obpyramidal, (3–)3.5–4.5 × 1–1.2 mm (l/w: 2.8–4.1), apex broadly conic, with sparse or moderately dense stipitate-glandular hairs on ribs, less densely pubescent or glabrous in sulci [rarely entirely glabrous]; ribs 5, round, smooth; sulci ± 2–2.5 times as wide as base of ribs, not rugose, not papillate. |
1–7 per umbel, straw colored or gray-brown, obpyramidal, 2.5–3.1 × 1.3–1.9 mm (l/w: 1.6–2.1), base stipelike, apex round-truncate, glabrous; ribs 3–4(–5), acute or winglike, tapering to pedicel, slightly rugose or undulate near sulci; sulci 0.5–1 times as wide as base of ribs, coarsely transversely rugose, smooth or very faintly papillate. |
2n | = 26, 52, 54, 116. |
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Boerhavia diffusa |
Boerhavia triquetra |
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Phenology | Flowering mid winter–early fall [year-round]. | Flowering summer–late fall. |
Habitat | Disturbed areas, waste places, roadsides, dry pinelands, among scrub on tropical reefs | Sandy or gravelly areas in deserts |
Elevation | 0-50[-1800] m (0-200[-5900] ft) | [0-]100-300 m ([0-]300-1000 ft) |
Distribution |
FL; GA; SC; Mexico; Central America; South America; West Indies; Asia; Africa; Indian Ocean Islands; Pacific Islands; Australia
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AZ; CA; Mexico (Baja California, Baja California Sur, Sonora)
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Discussion | Boerhavia diffusa belongs to a pantropical complex whose distribution, because of differing taxonomic treatments, is not precisely discernable. In North America, the West Indies, and elsewhere, the complex has been treated as having one (e.g., R. W. Long and O. Lakela 1971; R. P. Wunderlin 1998) or two species (E. A. Kellogg 1988; J. K. Small 1913c; P. C. Standley 1918; C. Whitehouse 1996). In the latter situation various binomials have been used. The abrupt bend in the ribs near the fruit apex, making a broadly conic apex, seems to be a useful character for distinguishing most B. diffusa. The shape of the apex, the sparse pubescence of the fruit, the few fruits in individual terminal clusters, and the open, ± leafless inflorescence may have led R. E. Woodson Jr. and H. J. Kidd (1961) to suspect hybridization of this complex with the annual B. erecta. Hybridization is plausible (R. Spellenberg 2000), but clearly intermediate plants are not known. The leaves are sometimes used as a vegetable (C. Whitehouse 1996). Extracts from roots are used to prepare an expectorant, a diuretic, and a laxative, and in treating asthma (S. P. Ambasta 1986). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Boerhavia triquetra, very narrowly defined here by a predominance of 3- and 4-ribbed fruits, is uncommon in the flora, known to occur only on low deserts near the Colorado River and southward around the Sea of Cortez. The species has few- or 1-flowered terminal inflorescences. Its relationship to, and distinctness from, B. intermedia, needs clarification. In the area of the type locality, Bahia de los Angeles, on the east coast of Baja California, some plants have only 3- and 4-winged fruits, whereas most will have 3-, 4-, and some 5-winged fruits. The five-winged fruits do not differ from those of B. intermedia, a species common on the peninsula. Intergradient plants occur on the peninsula and on islands in the gulf. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 4, p. 19. | FNA vol. 4, p. 24. |
Parent taxa | Nyctaginaceae > Boerhavia | Nyctaginaceae > Boerhavia |
Sibling taxa | ||
Name authority | Linnaeus: Sp. Pl. 1: 3. (1753) | S. Watson: Proc. Amer. Acad. Arts 24: 69. (1889) |
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