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American black nightshade, American black or common or West Indian nightshade, glossy nightshade, little white nightshade, small-flower nightshade, white nightshade

earleaf nightshade

Habit Herbs to subshrubs, annual to perennial, erect, unarmed, to 1.5 m, glabrate to moderately pubescent, hairs whitish, unbranched, to 1 mm, eglandular. Shrubs or small trees, erect, unarmed, 2–12 m, densely pubescent, hairs white, sessile to long-stalked, stellate to echinoid.
Leaves

petiolate;

petiole 1–4 cm;

blade simple, ovate to ovate-elliptic, 2–10.5 × 1–4.5 cm, margins entire or shallowly sinuate-dentate, base decurrent.

petiolate;

petiole 1–8 cm;

blade simple, elliptic to ovate, 11–31 × 4–14 cm, margins entire, base acute, often with smaller axillary leaves.

Inflorescences

extra-axillary or leaf-opposed, unbranched, usually umbel-like, 3–10-flowered, 0.5–3 cm.

terminal, becoming leaf-opposed, much-branched, 50–100-flowered, 5–24 cm.

Pedicels

erect or spreading, 0.3–1 cm in flower, to 1.5 cm in fruit.

erect and 0.2–0.5 cm in flower and fruit.

Flowers

radially symmetric;

calyx somewhat accrescent, unarmed, 1–3 mm, lobes deltate, strongly reflexed in fruit;

corolla white, sometimes with yellowish central star, stellate, 0.4–0.8 cm diam., without interpetalar tissue;

stamens equal;

anthers ellipsoidal, 0.7–1.5 mm, dehiscent by terminal pores that open into longitudinal slits;

ovary glabrous.

radially symmetric;

calyx slightly accrescent, unarmed, 4–7.5 mm, densely pubescent, lobes deltate;

corolla purple, stellate-pentagonal, 1–1.5 cm diam., with abundant interpetalar tissue;

stamens equal;

anthers oblong, 2–3.5 mm, dehiscent by terminal pores that open into longitudinal slits;

ovary tomentose.

Berries

shiny purplish black, globose, 0.5–1 cm diam., glabrous, with (0–)2–4(–6) sclerotic granules, usually 2–4 larger and 2 smaller.

yellow, globose, 1–1.5 cm diam., tomentose, without sclerotic granules.

Seeds

pale yellow to brown, 1–1.5 × 0.5–1.5 mm, minutely pitted.

yellowish brown, flattened, 1.5–2.5 × 1.5–2 mm, minutely pitted.

2n

= 24.

= 24.

Solanum americanum

Solanum mauritianum

Phenology Flowering May–Nov (year-round in Fla.). Flowering Mar–Jul.
Habitat Weedy habitats, secondary forest, disturbed areas. Disturbed sites.
Elevation 0–1000(–2000) m. (0–3300(–6600) ft.) 0–500 m. (0–1600 ft.)
Distribution
from FNA
AL; AZ; CA; FL; GA; LA; MO; MS; OR; SC; TX; UT; WA; BC; Mexico; Central America; South America; West Indies [Introduced in Europe, Asia, Africa, Pacific Islands, Australia]
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; FL; South America (Brazil, Uruguay) [Introduced also in Asia (India), Africa, Atlantic Islands, Indian Ocean Islands, Pacific Islands, Australia]
[BONAP county map]
Discussion

Solanum americanum is a morphologically variable and globally distributed weedy species. It has often been confused with other species in the black nightshade group such as S. emulans, S. nigrescens, S. nigrum, and S. pseudogracile and has often been referred to as S. nodiflorum in floristic treatments. It is distinguished by its very short anthers and shiny black mature fruits with strongly reflexed calyx lobes and usually two to four (rarely none or as many as six) sclerotic granules per fruit. Leaf shape and pubescence can vary considerably throughout its range, and there are some suspected cases of introgression with other species such as S. nigrescens or S. pseudogracile. The name S. nigrum has been misapplied to S. americanum (for example, A. E. Radford et al. 1968).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

In Florida, Solanum mauritianum has become naturalized and common only at one site in Pasco County. It also occurs frequently in southern California from Santa Barbara south to San Diego with urban waifs in the Bay Area. It appears to be spreading into relatively undisturbed riparian areas in the San Gabriel Mountains and may become a widespread pest.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 14. FNA vol. 14.
Parent taxa Solanaceae > Solanum Solanaceae > Solanum
Sibling taxa
S. aviculare, S. bahamense, S. campechiense, S. capsicoides, S. carolinense, S. chenopodioides, S. citrullifolium, S. cordicitum, S. davisense, S. deflexum, S. dimidiatum, S. diphyllum, S. donianum, S. douglasii, S. dulcamara, S. elaeagnifolium, S. emulans, S. erianthum, S. furcatum, S. hindsianum, S. interius, S. jamaicense, S. jamesii, S. laciniatum, S. lanceolatum, S. lumholtzianum, S. lycopersicum, S. marginatum, S. mauritianum, S. nigrescens, S. nigrum, S. nitidibaccatum, S. novomexicanum, S. perplexum, S. pseudocapsicum, S. pseudogracile, S. pumilum, S. rostratum, S. sarrachoides, S. seaforthianum, S. setigeroides, S. sisymbriifolium, S. stoloniferum, S. tampicense, S. tenuipes, S. torvum, S. triflorum, S. triquetrum, S. umbelliferum, S. viarum, S. wallacei
S. americanum, S. aviculare, S. bahamense, S. campechiense, S. capsicoides, S. carolinense, S. chenopodioides, S. citrullifolium, S. cordicitum, S. davisense, S. deflexum, S. dimidiatum, S. diphyllum, S. donianum, S. douglasii, S. dulcamara, S. elaeagnifolium, S. emulans, S. erianthum, S. furcatum, S. hindsianum, S. interius, S. jamaicense, S. jamesii, S. laciniatum, S. lanceolatum, S. lumholtzianum, S. lycopersicum, S. marginatum, S. nigrescens, S. nigrum, S. nitidibaccatum, S. novomexicanum, S. perplexum, S. pseudocapsicum, S. pseudogracile, S. pumilum, S. rostratum, S. sarrachoides, S. seaforthianum, S. setigeroides, S. sisymbriifolium, S. stoloniferum, S. tampicense, S. tenuipes, S. torvum, S. triflorum, S. triquetrum, S. umbelliferum, S. viarum, S. wallacei
Synonyms S. nigrum var. americanum, S. nigrum var. nodiflorum, S. nodiflorum, S. ptychanthum S. auriculatum
Name authority Miller: Gard. Dict. ed. 8 Solanum no. 5. (1768) Scopoli: Delic. Fl. Faun. Insubr. 3: 16, plate 8. (1788)
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