Solanum nitidibaccatum Bitter, Repert. Spec. Nov. Regni Veg. 11: 208. 1912, nom cons. prop.

Knapp, Sandra, Saerkinen, Tiina & Barboza, Gloria E., 2023, A revision of the South American species of the Morelloid clade (Solanum L., Solanaceae), PhytoKeys 231, pp. 1-342 : 1

34. Solanum nitidibaccatum Bitter, Repert. Spec. Nov. Regni Veg. 11: 208. 1912, nom cons. prop.

Figs 104 , 105

Solanum stylesanum Dunal, Prodr. [A. P. de Candolle] 13(1): 44. 1852, nom rej. prop., as ' styleanum ' Type. Chile. Sin. loc., J. Styles s.n. (holotype: G-DC [G00144016]).

Bosleria nevadensis A.Nelson, Proc. Biol. Soc. Washington 18(30): 175. 1905, nom rej. prop. Type. United States of America. Nevada: Washoe County, Pyramid Lake, 9 Jun 1903, G.H. True s.n. (holotype: RM [RM0004387]).

Solanum patagonicum C.V.Morton, Revis. Argentine Sp. Solanum 146. 1976. Type. Chile. Región XII (Magallanes): Río Paine, 100 m, 15 Jan 1931, A. Donat 415 (holotype: BM [BM000617673]; isotypes: BA, BAF, GH [GH00077732], K, SI [003331, 003332], US [00027733, acc. # 2639758]).

Solanum physalifolium Rusby var. nitidibaccatum (Bitter) Edmonds, Bot. J. Linn. Soc. 92: 27. 1986. Type. Based on Solanum nitidibaccatum Bitter.

Type.

Chile. Sin. loc., 1829, E.F. Poeppig s.n. (lectotype, designated by Edmonds 1986, pg. 27: W [acc. # 0004151]; isolectotype: F [v0073346F, acc. # 875221]) .

Description.

Annual herbs to 0.2 m high, prostrate and spreading to 0.3 m in diameter or more. Stems terete, green, not markedly hollow; new growth densely viscid-pubescent with translucent simple, uniseriate 2-8(10)-celled spreading trichomes 1.5-2 mm long with a glandular apical cell; older stems glabrescent. Sympodial units difoliate, the leaves not geminate. Leaves simple and shallowly toothed, the blades 2-5.5(-9.5) cm long, 1.5-5(-6.5) cm wide, ovate to broadly ovate, rarely elliptic, widest in the lower half to third, membranous, discolorous; adaxial surface sparsely pubescent with spreading 2-4-celled translucent, simple, uniseriate gland-tipped trichomes like those of the stem, these denser along the veins; abaxial surface more evenly densely pubescent on the lamina and veins; major veins 3-6 pairs, not clearly evident abaxially; base attenuate to cuneate, at times asymmetric, decurrent on the petiole; margins entire or sinuate-dentate; apex acute to obtuse; petioles 0.5-2.7(-4.5) cm long, sparsely pubescent with simple uniseriate glandular trichomes like those of the stems and leaves. Inflorescences generally internodal, but in new growth appearing to arise opposite the leaves, unbranched, 1-2 cm long, with 4-8(-10) flowers clustered at the tip (sub-umbelliform) or spread along a short flower-bearing portion of the axis, sparsely pubescent with spreading trichomes like those on stems and leaves; peduncle 0.6-1.3 cm long; pedicels 4-12 mm long, 0.1-0.2 mm in diameter at the base and 0.2-0.4 mm in diameter at the apex, straight and spreading, articulated at the base; pedicel scars spaced 0.3-1 mm apart. Buds subglobose, the corolla only slightly exserted from the calyx tube before anthesis. Flowers 5-merous, cosexual (hermaphroditic). Calyx tube 1-2 mm long, conical, the lobes 1.7-2.5 mm long, less than 1 mm wide, triangular with acute to obtuse apices, sparsely pubescent with 1-4-celled glandular trichomes like those of the pedicels. Corolla 0.4-0.6 cm in diameter, white with a yellow-green central eye with black “V” or “U” shaped edges in the lobe sinuses, rotate-stellate, lobed 1/3 of the way to the base, the lobes 2.3-3.2 mm long, 2.5-3.7 mm wide, spreading at anthesis, sparsely papillate-pubescent abaxially with 1-4-celled simple uniseriate trichomes, especially along tips and midvein. Stamens equal; filament tube minute; free portion of the filaments 1.5-2 mm long, adaxially sparsely pubescent with tangled uniseriate 4-6-celled simple trichomes; anthers 1-1.4 mm long, 0.5-0.8 mm wide, ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age and drying. Ovary globose, glabrous; style 2.5-3 mm long, straight, exserted beyond the anther cone, densely pubescent with 2-3-celled simple uniseriate trichomes in the lower half where included in the anther cone; stigma capitate, minutely papillate, green in live plants. Fruit a globose berry, 0.4-1.3 cm in diameter, brownish green and marbled with white (this not easily visible in herbarium specimens) at maturity, translucent, the pericarp usually shiny, somewhat translucent, glabrous; fruiting pedicels 4-13 mm long, ca. 0.2 mm in diameter at the base, spaced 1-3 mm apart, reflexed and slightly curving, not persistent; fruiting calyx accrescent, becoming papery in mature fruit, the tube ca. 3 mm long, the lobes 2.5-3.5(-4) mm long and 3-4 mm wide, appressed against the berry, but the berry clearly visible. Seeds 13-24 per berry, 2-2.2 mm long, 1.2-1.4 mm wide, flattened and teardrop shaped with a subapical hilum, brown, the surfaces minutely pitted, the testal cells pentagonal in outline. Stone cells usually (1-)2-3 per berry, occasionally absent, ca. 0.5 mm in diameter. Chromosome number: n = 12 ( Moscone 1992, voucher Ambrosetti & Moscone 1478; Moyetta et al. 2013, voucher Chiapella et al. 1840, as S. sarrachoides ).

Distribution

(Fig. 106 ). Solanum nitidibaccatum has an amphitropical distribution in temperate South America and temperate western North America, including northern Baja California (for distribution outside South America and a discussion of its native range see Särkinen et al. 2018, Knapp et al. 2019). In South America it appears to be native in Chile (Regions III [Atacama], V [Valparaiso], VI [ O’Higgins], VIII [ Bío-Bío], XII [Magellanes], XIII [Metropolitana], XIV [Los Ríos]), Argentina (Provs. Buenos Aires, Catamarca, Chubut, Córdoba, Entre Rios, La Rioja, Mendoza, Neuquén, Río Negro, Salta, San Juan, San Luis, Santa Cruz, Santiago del Estero, Tucumán) and coastal southern Peru (Depts. Moquegua, Tacna); it is perhaps adventive in Ecuador (Prov. Tungurahua).

Ecology and habitat.

Solanum nitidibaccatum is a species that inhabits disturbed areas, usually found growing along roadsides in the shade of trees and shrubs, and in rocky and sandy soils between (0-) 1,200 and 2,500 m elevation. It is a common weed of agriculture and is often found growing in sandy soil in seasonal washes (arroyos).

Common names and uses.

No common names or uses have been recorded from South American specimens (for common names in North America, see Knapp et al. 2019). The many uses of S. nitidibaccatum by indigenous peoples of North America are documented in Knapp et al. (2019). In Argentina, the Mapuche people use S. nitidibaccatum medicinally for treatment of gastrointestinal and liver complaints ( Molares and Ladio 2012).

Preliminary conservation status

( IUCN 2022). Least Concern [LC]. EOO = 188,100,484 km2 [LC]; AOO = 1,824 km2 [EN]; calculated on the global range. Solanum nitidibaccatum is widespread and weedy throughout its range. In North America it is considered a noxious weed of agriculture (see Knapp et al. 2019).

Discussion.

Solanum nitidibaccatum is morphologically similar to and has been treated as S. sarrachoides in many previous treatments (e.g., Schilling 1981; Schilling and Heiser 1979); it is also often treated as S. physalifolium . Solanum nitidibaccatum has also sometimes been treated at infraspecific rank within S. physalifolium , an Andean endemic; the species are distinct and not closely related ( Gagnon et al. 2022). Solanum nitidibaccatum is usually thought to be native to Patagonian South America, from which it has been introduced extensively to other parts of the world where it has become a prolific and successful weed of disturbed sites. The species is locally abundant throughout North America and is probably native there west of the Rockies (see Knapp et al. 2019), as evidenced by its extensive use by local people.

Solanum nitidibaccatum can be distinguished from S. sarrachoides in its shorter, plumper anthers, the blackish purple markings in the centre of the corolla on the margins of the central star, and in its fruits that are shiny at maturity, marbled with white (not usually visible on herbarium sheets) and not completely enclosed in the accrescent calyx. In addition, the mature inflorescences of S. nitidibaccatum are always internodal while those of S. sarrachoides are usually opposite the geminate leaves. Edmonds (1986) showed that S. nitidibaccatum and S. sarrachoides were distinct morphologically and phylogenetic results confirm this, showing these two species are not closely related despite their overall similarity ( Särkinen et al. 2015b; Gagnon et al. 2022).

Solanum nitidibaccatum can be distinguished from other glandular-pubescent morelloids by its minute flowers, with anthers 1-1.5 mm long. Solanum marmoratum , with which S. nitidibaccatum is sympatric, has similarly tiny flowers, but lacks glandular pubescence completely and has much larger, more distinctly marbled berries.

Details of typification of the synonyms of S. nitidibaccatum can be found in Barboza et al. (2013) and Särkinen et al. (2018). The name S. nitidibaccatum has been proposed for conservation ( Särkinen and Knapp 2022) due to its widespread usage in the weed literature.

Figures

Figure 104. Solanum nitidibaccatum A habit B fruiting habit C fruiting habit showing leaf variation D detail of adaxial leaf surface E detail of abaxial leaf surface F flower bud G dissected flower H fruit (A, C, F Henning 14 B, D, E, H Blake 186 C Arnow 740). Illustration by R. Wise. Previously published in Saerkinen et al. (2018: 107) and Knapp et al. (2019: 92).

Figure 105. Solanum nitidibaccatum A habit B young inflorescence with flower buds C flowers at anthesis D maturing fruits (A-D Saerkinen et al. 4076). Photos by T. Saerkinen. Previously published in Saerkinen et al. (2018: 108) and Knapp et al. (2019: 93).

Figure 106. Distribution map of Solanum nitidibaccatum in South America. For distribution in North and Central America and the Caribbean, see Knapp et al. (2019: 95) and adventive distribution elsewhere, see Saerkinen et al. (2018: 109).