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red spiderling, spreading hogweed

largebract spiderling, Wright's boerhavia, Wright's spiderling

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, unbranched in small plants to ca. 1–5 times branched throughout, 20–60 dm, densely glandular-pubescent throughout.

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;

larger leaves with petiole 5–35 mm, blade ovate-triangular, ovate, or broadly lanceolate, 15–55 × 7–35 mm (distal leaves smaller, proportionately narrower), adaxial surface usually pubescent, often glandular, sometimes glabrate but with hairs along midrib, abaxial surface similar, somewhat paler, both surfaces often finely punctate with groups of brown cells, base usually round to obtuse, occasionally subtruncate, margins ± sinuate, apex acute, occasionally obtuse.

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, branched ca. 1–4 times unequally, without sticky internodal bands;

branches strongly ascending, terminating in spicate or racemose flower clusters, axis 10–35 mm.

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 0.3–0.7 mm;

bracts at base of perianth persistent, 1–2, ovate-acuminate, 1.5–4 mm;

perianth whitish to pale pink (rarely golden yellow), campanulate distal to constriction, 1.2–1.4 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.

4–15 per cluster, well spaced to completely overlapping, straw colored to tan at maturity, broadly obovoid, 2.1–2.5 × 1–2 mm (l/w: 1.3–2.1), apex rounded, glabrous;

ribs 4(–5), broadly acute, never winged, slightly rugose adjacent to sulci;

sulci 0.5–1 times as wide as base of ribs, coarsely transversely rugose, not papillate.

2n

= 26, 52, 54, 116.

= 54.

Boerhavia diffusa

Boerhavia wrightii

Phenology Flowering mid winter–early fall [year-round]. Flowering summer.
Habitat Disturbed areas, waste places, roadsides, dry pinelands, among scrub on tropical reefs Sandy soils, among desert shrubs
Elevation 0-50[-1800] m (0-200[-5900] ft) 400-1200 m (1300-3900 ft)
Distribution
from FNA
FL; GA; SC; Mexico; Central America; South America; West Indies; Asia; Africa; Indian Ocean Islands; Pacific Islands; Australia
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; NM; NV; TX; UT; Mexico (Chihuahua, Sonora)
[WildflowerSearch map]
[BONAP county map]
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.)

Source FNA vol. 4, p. 19. FNA vol. 4, p. 25.
Parent taxa Nyctaginaceae > Boerhavia Nyctaginaceae > Boerhavia
Sibling taxa
B. anisophylla, B. ciliata, B. coccinea, B. coulteri, B. erecta, B. gracillima, B. intermedia, B. linearifolia, B. megaptera, B. pterocarpa, B. purpurascens, B. spicata, B. torreyana, B. triquetra, B. wrightii
B. anisophylla, B. ciliata, B. coccinea, B. coulteri, B. diffusa, B. erecta, B. gracillima, B. intermedia, B. linearifolia, B. megaptera, B. pterocarpa, B. purpurascens, B. spicata, B. torreyana, B. triquetra
Name authority Linnaeus: Sp. Pl. 1: 3. (1753) A. Gray: Amer. J. Sci. Arts, ser. 2, 15: 322. (1853)
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