Brazil. “Brasilia australis”, F. Sellow s.n. (lectotype, designated by Edmonds 1986, pg. 16: P [P00371162]).

Annual herbs to 70 cm tall, usually smaller (but very rarely to 1 m), spreading and decumbent with age. Stems terete, green, generally erect, branching and later spreading, not markedly hollow; new growth densely viscid-pubescent with simple, uniseriate, spreading trichomes with a glandular apical cell, the trichomes of two lengths, 1–4-celled trichomes to 0.5 mm long and 5–14-celled trichomes to 2.0 mm long; older stems glabrescent. Sympodial units difoliate, the leaves not geminate. Leaves simple, 3.0–7.5 cm long, 3.0–6.0 cm wide, broadly ovate; adaxial and abaxial surfaces sparsely to densely pubescent with spreading, simple, uniseriate glandular trichomes like those of the stem, evenly distributed on lamina and veins; major veins 3–4 pairs; base truncate to cordate, sometimes asymmetric; margins entire or regularly sinuate-dentate; apex acute; petioles 0.5–3.2 cm long, sparsely pubescent with trichomes like those of the stem and leaves. Inflorescences 0.7–1.7 cm long, lateral, usually leaf-opposed but occasionally internodal (always very near the node), unbranched, with 2–5(6–7) flowers clustered at the tip (sub-umbelliform), sparsely pubescent with spreading trichomes like those of the stems; peduncle 0.7–1.0 cm long; pedicels 5–7 mm long, 0.1–0.2 mm in diameter at the base, 0.3–0.4 mm in diameter at the apex, straight and spreading, articulated at the base; pedicel scars spaced ca. 0(-1) mm apart. Buds globose, the corolla only slightly exserted from the calyx tube before anthesis, almost completely included within the calyx lobes and only the tip of the corolla showing. Flowers 5-merous, all perfect. Calyx tube 0.5–1.0 mm long, the lobes 1.5–2.0 mm long, 1.3–1.5 mm wide, lanceolate to narrowly ovate with acute apices, sparsely pubescent with 1–4-celled spreading glandular trichomes like those on the pedicels but shorter. Corolla 5–8 mm in diameter, white with a yellow-green central eye, pentagonal-stellate, lobed 1/2–1/3 of the way to the base, the lobes 3.0–4.5 mm long, 5.0–7.0 mm wide, spreading at anthesis, sparsely papillate-pubescent abaxially with glandular 1–4-celled simple uniseriate trichomes and eglandular papillae, these denser along margins, tips and midvein. Stamens equal; filament tube minute; free portion of the filaments 1.0–1.5 mm long, adaxially sparsely pubescent with tangled uniseriate 4–6-celled simple trichomes; anthers 1.2–2.0 mm long, 0.4–0.8 mm wide, ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age and drying. Ovary globose, glabrous; style 3.0–3.5 mm long, densely pubescent with 2–3-celled simple uniseriate trichomes in the lower 1/2–2/3 where included in the anther cone, not usually exserted beyond the anther cone; stigma capitate, minutely papillate, green in live plants. Fruit a globose berry, 6–9 mm in diameter, green-brownish grey at maturity, opaque, the surface of the pericarp usually matte; fruiting pedicels 5–9 mm long, 0.2–0.3 mm in diameter at the base, spaced 0–1 mm apart, reflexed, dropping with mature fruits, not persistent; fruiting calyx accrescent, becoming papery in mature fruit, the tube 3–4 mm long, the lobes 5.5–8.0 mm long and 3.5–4.0 mm wide, the tips slightly reflexed or spreading. Seeds (23-)59–69(-93) per berry, 1.3–1.7 mm long, 1.0–1.5 mm wide, flattened and tear-drop shaped with a subapical hilum, pale yellow, the surfaces minutely pitted, the testal cells pentagonal in outline. Stone cells 4–6 per berry, (0.5) 0.8–1 mm in diameter. Chromosome number: 2n=2×=24 (see Särkinen et al. 2018).

(Figure 47) Solanumsarrachoides is native to southern South America, and is sporadically introduced to North America, where it is much less common than the morphologically similar S.nitidibaccatum.

Sporadically occurs as a weed of cultivation 0–500 m elevation in urban areas, along riversides, and other disturbed areas (agriculture). Solanumsarrachoides is less common than S.nitidibaccatum as a weed of agriculture.

Canada and United States of America. Hairy nightshade (many sources, but unclear if individual accounts are referring to S.sarrachoides or S.nitidibaccatum).

None recorded.

Least Concern (LC). Solanumsarrachoides is introduced and weedy in the United States; it also occurs in southern South America. For EOO see Table 6.

Many accounts of North American black nightshades have treated as Solanumsarrachoides the species whose correct name is S.nitidibaccatum (e.g., Stebbins and Paddock 1949; Schilling and Heiser 1979; Schilling 1981). Records of S.sarrachoides in the North American literature should therefore be dealt with care due to common misidentification of voucher material. The two taxa can be distinguished based using the following suite of characters: S.sarrachoides has generally truncate leaf bases, leaf-opposed mature inflorescences that are umbellate to sub-umbellate with fewer flowers (2–5), shorter calyx lobes 1.0–1.4 mm long, and a corolla with yellow-green central eye. Solanumnitidibaccatum has cuneate leaf bases, usually internodal mature inflorescences that are racemose with more flowers (4–8), longer calyx lobes 1.8–2.5 mm long, and corolla with black-purple edged central eye. The accrescent calyx almost completely encloses the matte-surfaced mature berry in S.sarrachoides, while the shiny, marbled berry of S.nitidibaccatum is always ca. halfway exserted from the calyx lobes. Solanumsarrachoides usually has more stone cells in each berry (4–6) than does S.nitidibaccatum (1–2, or absent). Though morphologically very similar, preliminary data from both nuclear and plastid DNA sequences suggests the two species are not closely related (T. Särkinen, prelim. data).

Typification details of the synonyms of S.sarrachoides can be found in Barboza et al. (2013) and Särkinen et al. (2018).

See Suppl. materials 1 and 3.