PlantaeSolanalesSolanaceaeKnappSandraBarbozaGloria E.BohsLynnSärkinenTiinaA revision of the Morelloid Clade of Solanum L. (Solanaceae) in North and Central America and the CaribbeanPhytoKeys3052019123114410.3897/phytokeys.123.31738 Solanum nigrum L., Sp. Pl. 1: 186. 1753Figures 30, 31 Solanum peregrinum E.P.Bicknell, Bull. Torrey Bot. Club 42: 332. 1915. Type. United States of America. Massachusetts: Nantucket County, Nantucket street, E.P. Bricknell 7719 (holotype: NY [NY00138955]; isotype: NY [NY00073847]). Type.<sup><xref ref-type="fn" rid="en3">3</xref></sup>

“Habitat in Orbis totius cultis” [sheet marked with Θ, meaning central part of Asia = Middle East], Without collector s.n. (lectotype, designated by Henderson 1974, pg. 19: LINN [LINN 248-18]).

Description.

Annual or short-lived perennial herbs to 1.0 m tall, branching 10–30 cm from the base. Stems terete to sharply angled and ridged, green, the ridges often spinescent, not markedly hollow; new growth sparsely to densely pubescent with simple, spreading, uniseriate 1–6-celled trichomes 0.5–0.6 mm long, these eglandular and/or glandular; older stems glabrescent, the trichome bases persisting as pseudospines. Sympodial units difoliate, the leaves not geminate. Leaves simple, 3.8–7.2(–14.5) cm long, 2.5–5.0(–9.5) cm wide, broadly ovate, green; adaxial surface sparsely pubescent with spreading, simple, uniseriate trichomes like those on stem evenly scattered along veins and lamina; abaxial surface more densely pubescent along veins and sparsely along lamina with eglandular and/or glandular trichomes like those of the stems; major veins 5–7 pairs; base obtuse to truncate, somewhat attenuate; margins sinuate-dentate, especially in the lower 2/3, to occasionally entire or deeply toothed; apex acute; petioles 0.5–3.0 cm long, pubescent with simple uniseriate glandular and eglandular trichomes like those of the stems. Inflorescences 0.8–2.0 cm long, lateral, internodal, unbranched (occasionally forked), with (3-)4–10 flowers spaced along the rhachis, pubescent with spreading simple uniseriate trichomes like those on stem; peduncle 0.5–1.5 cm long, straight; pedicels 3–5 mm long, 0.2–0.3 mm in diameter at the base and 0.2–0.3 mm at the apex, spreading, articulated at the base; pedicel scars spaced 0.3–0.7 mm apart. Buds subglobose, the corolla approximately halfway exserted from the calyx before anthesis. Flowers 5-merous, all perfect. Calyx tube 0.8–1.0 mm long, the lobes 0.5–0.8 mm long, 0.6–0.8 mm wide, triangular with acute or somewhat rounded apices, pubescent with spreading simple uniseriate eglandular and glandular trichomes like those of the pedicels. Corolla 10–12 mm in diameter, white with a yellow-green central portion near the base, stellate, lobed 1/2 to 2/3 of the way to the base, the lobes 4.0–5.0 mm long, 2.0–2.5 mm wide, strongly reflexed at anthesis, later spreading, densely papillate-pubescent abaxially with simple uniseriate eglandular trichomes. Stamens equal; filament tube very short to minute; free portion of the filaments 0.5–0.7 mm long, adaxially pubescent with spreading uniseriate simple trichomes; anthers 1.8–2.5 mm long, 0.8–1.0 mm wide, ellipsoid, very slightly wider at base, yellow, poricidal at the tips, the pores lengthening to slits with age and drying. Ovary globose, glabrous; style 2.5–3.5 mm long, densely pubescent with tangled 2–3-celled simple uniseriate trichomes in the lower half where included in the anther cone, exserted 0–1 mm beyond anther cone; stigma capitate, minutely papillate, green in live plants. Fruit a globose berry, 6–10 mm in diameter, purple-black or green to yellowish green at maturity, opaque, the surface of the pericarp matte or slightly shiny; fruiting pedicels 10–12 mm long, 0.4–0.5 mm in diameter at the base, 1.0–1.1 mm in diameter at the apex, generally spreading to occasionally recurved, spaced 1.0–2.0 mm apart, dropping with mature fruits, usually not persistent but occasionally remaining on the rhachis; fruiting calyx not accrescent, tube 0.7–1.5 mm long, the lobes 1.0–2.0 mm long, spreading to reflexed in fruit. Seeds (15-)20–40 per berry, 1.8–2.0 mm long, 1.5–1.6 mm wide, flattened and tear-drop shaped with a subapical hilum, yellow, the surfaces minutely pitted, the testal cells pentagonal in outline. Stone cells absent (North America and Europe) but usually 2(-8) per berry in other areas (Asia), ca. 0.5 mm in diameter, brown. Chromosome number: 2n=6×=72 (for vouchers and references see Särkinen et al. 2018).

Solanumnigrum L. A Habit B flower (A ,BSymon 5449 [ADW 35964]). Drawing by M.L. Szent-Ivany, first published in Symon (1981), courtesy of the Board of the Botanic Gardens and State Herbarium (Adelaide, South Australia), reproduced with permission (previously also published in “PhytoKeys 106”).

Solanumnigrum L. A Habit B inflorescence (dense indumentum) C inflorescence (sparse indumentum) D fully mature full-black berries, calyx lobes remaining appressed or slightly spreading (A Nijmegen acc. 824750016 B Nijmegen acc. A34750479 C Nijmegen accession 824750029A D Nijmegen accession A44750150). Photos by S. Knapp (previously published in “PhytoKeys 106”).

Distribution.

(Figure 32) Solanumnigrum is native to Eurasia and has been sporadically introduced and locally naturalised in temperate North America. It is possible that populations from eastern and western areas have different origins (see below).

Distribution of Solanumnigrum L.

Ecology.

The species is found in disturbed areas between 0–2,200 m elevation in its native range, but around cities and cultivated fields from sea level to 700 m in North America.

Common names.

Canada. Black nightshade, morelle noire (Alex et al. 1980; Bassett and Munro 1985). United States of America. Black nightshade (many sources).

Uses.

None recorded for the region (see Särkinen et al. 2018 for uses in its native range).

Preliminary conservation status (<xref ref-type="bibr" rid="B115">IUCN 2017</xref>).

Least Concern (LC). See Särkinen et al. 2018.

Discussion.

Solanumnigrum is probably introduced in temperate North America; populations on the eastern seaboard best match European populations in overall morphology. Populations from the western coast (e.g., British Colombia) are morphologically more similar to Eurasian plants and it is possible that they are the result either of introductions from that region over the Pacific or are relictual native plants that came across the Bering Straits during warm periods in the Quaternary (e.g., DeChaine 2008; Ickert-Bond et al. 2009). Molecular population genetic analysis of these populations has not been done but should shed some light on the status of S.nigrum in North America.

Solanumnigrum can be distinguished from other North American species (e.g., S.americanum, S.douglasii, S.emulans, S.interius, S.nigrescens) in the character combination of thicker peduncles and pedicels, larger seeds and fruits lacking stone cells. It has longer anthers (2.5–3 mm) than S.emulans and S.americanum, both of which have tiny anthers ca. 1.5 mm long. Like S.nigrescens, it has inflorescences with the flowers spaced along the rhachis, but S.nigrescens has prominent stone cells in the berries and smaller seeds. Solanuminterius has similarly large seeds but has fewer flowers per inflorescence and distinctive basal flower pedicel position (articulation above the join with the rhachis).

Michael Nee (pers. comm.) has observed its spread and increase in the New York City area over the last decade; it is possible that more collections will be made throughout North America in the coming years.

For typification details of the many synonyms of S.nigrum see Särkinen et al. (2018).

Specimens examined.

See Suppl. materials 1 and 3.

Specimens cited in pdf format (traditional format; only specimens from the region cited)

Data type: PDF file

This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited.Sandra Knapp, Gloria E. Barboza, Lynn Bohs, Tiina Särkinen

Searchable CSV file of all specimens examined for this treatment, including Old World and South America

Data type: CSV file

This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited.Sandra Knapp, Gloria E. Barboza, Lynn Bohs, Tiina Särkinen

Types based on American specimens only, for full synonymy see Särkinen et al. (2018: 92–96)

SymonDE (1981) A revision of the genus Solanum in Australia.Journal of the Adelaide Botanic Gardens4: 1367.HendersonRJF (1974) Solanumnigrum L. (Solanaceae) and related species in Australia.Contributions from the Queensland Herbarium16: 178.SärkinenTPoczaiPBarbozaGEvan der WeerdenGMBadenMKnappS (2018) A revision of the Old World black nightshades (Morelloid clade of Solanum L., Solanaceae).PhytoKeys106: 1223. https://doi.org/10.3897/phytokeys.106.21991AlexJFCayoutteRMulliganGA (1980) Common and botanical names of weeds in Canada/Noms populaire et scientifiques des plantes nuisables du Canada. Ontario Publication 1397. Canadian Department of Agriculture, Ottawa.BassettIJMunroDB (1985) The biology of Canadian weeds 67. Solanumptycanthum Dun., S.nigrum L. and S.sarrachoides Sendt.Canadian Journal of Plant Science65(2): 401414. https://doi.org/10.4141/cjps85-055IUCN (2017) Guidelines for Using the IUCN Red List Categories and Criteria. Version 13. Prepared by the Standards and Petitions Subcommittee. http://www.iucnredlist.org/documents/RedListGuidelines.pdfDeChaineE (2008) A bridge or a barrier? Beringia’s influence on the distribution and diversity of tundra plants.Plant Ecology & Diversity1(2): 197207. https://doi.org/10.1080/17550870802328660Ickert-BondSMMurrayDFDeChaineE (2009) Contrasting patterns of plant distribution in Beringia.Alaska Park Science8(2): 2632.