Solanum chenopodioides Lam., Tabl. Encycl. 2: 18. 1794

Saerkinen, Tiina, Poczai, Peter, Barboza, Gloria E., Weerden, Gerard M. van der, Baden, Maria & Knapp, Sandra, 2018, A revision of the Old World Black Nightshades (Morelloid clade of Solanum L., Solanaceae), PhytoKeys 106, pp. 1-223 : 1

3. Solanum chenopodioides Lam., Tabl. Encycl. 2: 18. 1794 Figures 10 , 11

Solanum sublobatum Willd. ex Roem. & Schult., Syst. Veg., ed. 15 bis [Roemer & Schultes] 4: 664. 1819.

Solanum sublobatum Type. Argentina. Buenos Aires, Anon. s.n. [probably P. Commerson] (Herb. Willdenow 4336) (lectotype, designated by Edmonds 1972, pg. 105 [as type ex photo]: B [B-W04336-01-0]).

Solanum besseri Weinm., Syst. Veg., ed. 15 bis [Roemer & Schultes] 4: 593. 1819.

Solanum sublobatum Type. "In America" [cultivated in Europe?], Anon. s.n. (no specimens cited; no original material located; neotype, designated here: G-DC [G00144198]).

Solanum subspatulatum Sendtn., Fl. Bras. (Martius) 10: 45, tab. 4, fig. 16-18. 1846.

Solanum sublobatum Type. Brazil. Sin. loc., F. Sellow s.n. (holotype: B, destroyed, F neg. 3183; lectotype, designated by D’Arcy 1974a, pg. 735 [as type]: P [P00384051]; isolectotype: F [fragment]).

Witheringia chenopodioides (Lam.) J. Rémy, Fl. Chil. [Gay] 5: 69. 1849.

Solanum sublobatum Type. Based on Solanum chenopodioides Lam.

Solanum isabellei Dunal, Prodr. [A. P. de Candolle] 13(1): 153. 1852.

Solanum sublobatum Type. Uruguay. Montevideo, Lat. aust. 34°45 ’08”, 1838, A. Isabelle s.n. (lectotype, designated here: G-DC (G00145645); isolectotypes: F [V0073298F, acc. # 680251; V0073299F, acc. # 680253)], K [K000585686], P [P00384071], W [1889-115034]).

Solanum chenopodifolium Dunal, Prodr. [A. P. de Candolle] 13(1): 44. 1852.

Solanum sublobatum Type. Argentina/Uruguay. "Buenos Aires et Montevideo", P. Commerson s.n. (lectotype, designated Edmonds 1972, pg. 108 [as holotype], second step designated here: P [P00384081]).

Solanum crenatodentatum Dunal var. ramosissimum Dunal, Prodr. [A. P. de Candolle] 13(1): 54. 1852.

Solanum sublobatum Type. United States of America. Louisiana: "Basse Louisiane", 1839, G.D. Barbe 82 (holotype: P [P00362535]).

Solanum gracile Dunal, Prodr. [A.P. de Candolle] 13(1): 54. 1852, nom. illeg., not Solanum gracile Sendtn. (1846).

Solanum sublobatum Type. Brazil. Rio de Janeiro: "Rio de Janeiro", 1831-1833, C. Gaudichaud 520 (lectotype, designated by Henderson 1974, pg. 46: G-DC [G00144391]; isolectotypes: G [G00343457], P [P00384052, P00384053]).

Solanum gracile Dunal var. microphyllum Dunal, Prodr. [A. P. de Candolle] 13(1): 54. 1852.

Solanum sublobatum Type. Argentina/Uruguay. " Circa Buenos Ayres et Montevideo", P. Commerson s.n. (lectotype, designated by Morton 1976, pg. 151: P [P00384061, Morton neg. 8207]; possible isolectotype: F [V0073283F, acc. # 976485, fragment only]).

Solanum nodiflorum Jacq. var. microphyllum Hassl., Repert. Spec. Nov. Regni Veg. 9: 118. 1911.

Solanum sublobatum Type. Paraguay. Estrella: Mar, É. Hassler 10271 (holotype: G?, Morton photo 8612).

Solanum vile Bitter, Repert. Spec. Nov. Regni Veg. 11: 221. 1912.

Solanum sublobatum Type. Brazil. Rio de Janeiro: Restinga do Harpoador, E. Ule 4310 (lectotype, designated here: CORD [CORD00004277]; isolectotype: HBG [HBG511507]).

Solanum gracilius Herter, Rev. Sudamer. Bot. 7: 266. 1943.

Solanum sublobatum Type. Based on (replacement name for) S. gracile Dunal

Solanum ottonis Hyl., Uppsala Univ. Årsskr. 7: 279. 1945.

Solanum sublobatum Type. Based on (replacement name for) Solanum gracile Dunal

Solanum americanum Mill. var. baylisii D’Arcy, Ann. Missouri Bot. Gard. 61: 837. 1974.

Solanum sublobatum Type. New Zealand. Sin. loc., cultivated, 1953, Momson s.n. (holotype: OTA [OTA-00419]).

Type.

Mauritius. "Ex ins. Mauritiana", Herb. Lamarck s.n. (lectotype, designated by Barboza et al. 2013, pg. 242: P [P00357629]).

Description.

Annual herbs to short-lived, erect to somewhat sprawling perennial herbs to 1.0 m tall, subwoody and branching at base. Stems spreading to decumbent, terete, green-grey to straw colour, older stems with no prickle-like projections, not markedly hollow; new growth pubescent with simple, appressed, uniseriate, eglandular trichomes, these 1-6-celled, 0.1-0.6 mm long; older stems more sparsely pubescent, glabrescent. Sympodial units difoliate, the leaves not geminate. Leaves simple, 1.5-5.5(-7.0) cm long, 0.5-3.0(-3.5) cm wide, lanceolate to narrowly ovate, rarely ovate, discolorous; adaxial surface green, sparsely pubescent with appressed 1-4-celled translucent, simple, uniseriate trichomes like those on stem, these denser along the veins; abaxial surface pale grey, more densely pubescent with trichomes like those of the upper surface evenly across lamina and veins; major veins 3-6 pairs, not clearly evident abaxially; base attenuate, decurrent on the petiole; margins entire or sinuate; apex acute to obtuse; petioles (0.5-)1.0-1.5(-3.5) cm long, sparsely pubescent with simple uniseriate trichomes like those of the stems and leaves. Inflorescences 1.0-2.5(-4.0) cm long, generally internodal but appearing leaf-opposed on young shoots, simple or rarely furcate, sub-umbelliform, with 3-7(-10) flowers, sparsely pubescent with appressed 1-2-celled simple uniseriate trichomes; peduncle 1.0-2.3(-4.0) cm long, straight but becoming strongly deflexed downwards in fruit; pedicels 0.5-1 cm long, ca. 0.5 mm in diameter at the base and 1 mm at apex, straight and spreading, articulated at the base; pedicel scars spaced ca. 0-1 mm apart. Buds elongate-oblong, the corolla only slightly exserted from the calyx tube before anthesis. Flowers 5-merous, all perfect. Calyx tube 0.5-1.0 mm long, conical, the lobes 0.6-1.2 mm long, less than 1 mm wide, broadly deltate to triangular with acute to obtuse apices, sparsely pubescent with 1-4-celled appressed hairs like those on stem but shorter. Corolla 6-12 mm in diameter, white with a black or yellow-green central portion near the base, the black colour usually distal to the yellow-green, deeply stellate, lobed 4/5 of the way to the base, the lobes 3.5-4.0 mm long, 1.5-1.9 mm wide, strongly reflexed at anthesis, later spreading, densely puberulent-papillate abaxially with 1-4-celled simple uniseriate trichomes, these denser on the tips and margins. Stamens equal; filament tube minute; free portion of the filaments 0.6-1.0 mm long, adaxially pubescent with tangled uniseriate 4-6-celled simple trichomes; anthers (2.0-)2.3-2.8 mm long, 0.5-0.8 mm wide, narrowly ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age and drying, the connective becoming darker brown with age in dry plants. Ovary globose, glabrous; style 3.7-4.5 mm long, densely pubescent with 2-3-celled simple uniseriate trichomes in the lower half where included in the anther cone, exserted up to 1.5 mm beyond the anther cone; stigma capitate, minutely papillate, green in live plants. Fruit a globose berry, 4-9 mm in diameter, dull purplish-black at maturity, the pericarp thin and opaque, matte and somewhat glaucous; fruiting pedicels 6-13 mm long, 1.2-1.4 mm in diameter at the base and the apex, reflexed and slightly curving, dropping with mature fruits, not persistent; fruiting calyx not accrescent, the tube less than 1 mm long, the lobes 1-1.5 mm long, appressed against the berry. Seeds (13-)20-35(-50) per berry, 1.2-1.4 mm long, 1.0-1.2 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 absent or occasionally 1-2 diminutive apical stone cells present. Chromosome number: 2n =2x=24 ( Baylis 1958; Soria and Heiser 1961 [as S. gracile ]; Heiser et al. 1965 [as S. gracile ]; Venkateswarlu and Rao 1972; Henderson 1974 [as S. gracilius ]; Randell and Symon 1976; Edmonds 1972, 1977, 1982, 1983; 1984a [as S. sublobatum ]; Moscone 1992; Jacoby and Labuschagne 2006; Moyetta et al. 2013).

Distribution

(Figure 12 ). Thought to be native to southern South America (see Barboza et al. 2013), but introduced globally in temperate and subtropical areas.

Ecology.

Grows in humid, disturbed areas between rocks, along water sources and roads and in cultivated lands, common in areas with human disturbance; between sea level and 1,900 (-2,500) m elevation.

Common names.

Australia: whitetip nightshade ( Symon 1981; Edmonds and Chweya 1997); New Zealand: velvety nightshade ( Webb et al. 1988; Edmonds and Chweya 1997); South Africa: nastergal; United Kingdom: tall nightshade ( Stace 2010).

Uses.

South Africa. leaves used as spinach ( Edmonds and Chweya 1997); berries locally used for making jam ( Viljoen 2011).

Preliminary conservation status

( IUCN 2016). Solanum chenopodioides is an extremely widespread cosmopolitan weed and can be assessed as LC (Least Concern; Table 7 ). When only the putatively native South American distribution is considered, S. chenopodioides still has a very large EOO of 2,279,138 km2 and remains LC.

Discussion.

Solanum chenopodioides can be distinguished from most of the other morelloids occurring in the Old World based on its narrowly lanceolate leaves with grey indumentum, inflorescences with ca. 3-7 flowers tightly congested near the tip of the peduncle, the stellate corollas that are deeply lobed to the base and usually with a dark purple or black central star and anthers that are usually more than 2 mm and up to 2.8 mm long. In fruit, the pedicels and proximal portion of the peduncle are strongly reflexed and the berries are not at all shiny. Solanum retroflexum has similar matte black berries, but has rhomboid leaves, less deeply divided corollas, shorter anthers and the calyx lobes are strongly reflexed in fruit. Solanum chenopodioides could also potentially be confused with the more common S. nigrum , especially in Europe, but differs from that species in its terete stems, matte black fruits on short strongly reflexed pedicels and its smaller seeds (1.2 mm long versus 2 mm long).

Solanum chenopodioides has a scattered distribution in the Old World, but it seems to be spreading, perhaps related to climate change and/or increased habitat alteration ( Martínez Labarga et al. 2017).

This diploid species possibly contributed its genome to the tetraploid S. retroflexum and hexaploid S. opacum . Jacoby and Labuschagne (2006) reported that crosses made between S. chenopodioides and S. retroflexum were much more successful than between S. americanum and S. retroflexum . This relationship was also confirmed by arbitrary-amplified dominant markers ( Jacoby et al. 2003; Poczai and Hyvönen 2011) and by whole genome DArT analysis by van der Walt et al. (2008).

Morton (1976) thought the locality on the type specimen of S. chenopodioides Lam. as “Mauritius” was in error, because the species was a New World taxon in his concept. Morton suggested that the Commerson material on which the name was based was actually from Argentina, but that the localities had been mixed up. This may be true, because there is much material collected by Commerson from Argentina and Uruguay, but S. chenopodioides also occurs on Mauritius as an introduced weed and we are hence reluctant to suggest the locality is an error.

In the protologue ( Roemer and Schultes 1819: 593) of S. besseri , both the name and description are attributed to Johann Anton Weinmann ("Weinm. in litt.") but no specimens or collections are cited. The description is of a plant with subumbellate inflorescences, black fruits and that comes from America, meaning that, in the absence of a type specimen, it is difficult to determine the identity of this species. Later Weinmann (1824) published a list of plants from St. Petersburg in which he lists " S. besserianum " (a nomen nudum with no description) that is probably the same plant, stating it is from “America” and equating it with " S. cestrifolium Jacq.?" (see Doubtful names). Dunal (1852) made a detailed description of S. besseri and put S. americanum in synonymy with it. His description was based on a specimen he saw in "herb. DC" and living plants. In the absence of any original material for this name, we neotypify it here with the specimen in G-DC (G00144198) used by Dunal (1852) and labelled " Solanum besseri " in his hand. The specimen matches his detailed description exactly and it is not in conflict with the original description ( Roemer and Schultes 1819). We do this in order to stabilise the identity of this name so it does not further disrupt names in this group (e.g. see discussions of S. memphiticum and S. villosum ).

In the protologue of S. isabellei , Dunal (1852) cited specimens in G-DC (Isabelle s.n.) and P (Gay s.n., 1828); we have selected the collection Isabelle s.n. (G00145645) as the lectotype because it is well represented by duplicates in other herbaria. He cited various sheets of plants collected by Philibert Commerson in Uruguay and Argentina as material for his new names S. chenopodiifolium , S. gracile and S. gracile var. microphyllum . There are many Commerson collections corresponding to S. chenopodioides in P, none of which we are treating as strict duplicates; although they have similar morphologies, they all have slightly different collecting localities and labels. Conrad V. Morton (1976) lectotypified S. gracile var. microphyllum by citing his photograph (Morton neg. 8207) of specimens in P and we have matched this to the individual sheet and add the barcode here as a second step lectotypification. We have selected another of the Commerson sheets in P that is annotated by Dunal as " S. chenopodiifolium " as the lectotype of that name.

Solanum gracile was incorrectly typified by D’Arcy (1974a) on "Hort. Monsp. 1831 (MPU)", but Dunal did not cite herbarium material from Montpellier, he only cited living material from there ( “v.v.”) along with herbarium material from G-DC and P ("v.s. in h. DC h. Mus Paris. et v.v."). Any herbarium material prepared from such living specimens would be a neotype, but that is inappropriate while syntypes still exist. Henderson (1974) cited as lectotype for S. gracile a sheet in G-DC without citing a collector, but he did cite a microfiche number (IDC 800-61.2063:III.7) that corresponds to Gaudichaud 520, the material cited in the protologue. His lectotypifcation is effective, because he cited a single collection in a single herbarium (G-DC, G003144391); duplicates in G and P are isolectotypes. Morton (1976) later superfluously lectotypified S. gracile with Commerson material at P, citing his photograph (Morton neg. 8206); this specimen (P00384083) is not a type, although it was cited as the lectotype by Barboza et al. (2013).

Selected specimens examined.

Australia. New South Wales: N shore Lake Illawarra, Lake Hts, 5 Sep 2003, Andrew s.n. (WOLL); Nepean River, Douglas Park, 6 mi E of Picton, 11 Oct 1965, Constable 6161 (AD, K, NSW); Bega Valley, Twofold Bay, Nullica Bay Beach 5 km SSW of Eden, 8 Feb 1979, Haegi 1711 (AD, MEL, MO, NSW); Swamp 2 km N of Bodalla on Princes H[igh]w[a]y, just S of Tuross River crossing, 10 Feb 1979, Haegi 1756 (AD, NSW); Bega Valley, Tathra, 20 Mar 1995, Heyligers 95004 (PERTH); Bega Valley, Tathra, 20 Mar 1995, Heyligers 95006 (PERTH); Tamworth Regional, Hanging Rock, 13 Apr 2008, Hosking 3091 (CANB, MEL, NE, NSW); Murrumbidgee River at Cotter Bridge, Cotter Reserve, 1 Mar 1992, Lepschi 740 (AD, CANB, NSW); Hillview (3 mi SW of Liverpool), 11 Dec 1968, Rodd s.n. (NSW); Queensland: Brisbane, 20 Jan 1966, Henderson 128 (BRI, NSW); Brisbane, Clapham Junction, 20 Oct 1967, Henderson 301 (AD, BRI); South Australia: Tea Tree Gully, Gorge Rd, 15 Jan 2010, Brodie 1171 (AD); sin. loc, 1885, Lea s.n. (BM); Region 11, Southern Lofty, Lower Gorge Rd, 13 Feb 1997, Symon 15462 (AD, K, MEL); Victoria: East Gippsland, N of Mallacoota township, 4 Apr 1999, Clarke 2890 (AD, MEL); Melbourne, 70 m SW of Queens Bridge, 18 Feb 1983, Clarke 1544 (AD, CANB, MEL); Wellington, c. 13 km from Licola, 28 Jan 1989, Thompson 159 (AD).

France. Nouvelle Aquitaine: Gironde, Bordeaux , 28 Aug 1931, Bouchon 6703 (BM); Provence-Alpes-Côte d’Azur: Bouches-du-Rhône, La Valentine, banlieue E de Marseille, route vers Saint Menet, 19 Nov 1973, Martin 6848 (BM, H) .

Germany. Baden-Württemberg: Karlsruhe, Carlsruhe , Oct 1834, Braun s.n. (K); Karlsruhe [?], Dec 1834, Braun s.n. (K) .

Greece. Crete: sin. loc, de Tournefort s.n. (BM) ; East Macedonia and Thrace: Island of Thasos , SE of Potamia, 23 Nov 2016, Biel IM-16054 (N/A) .

Italy. Friuli Venezia Giulia: Monfalcone, Friulia , 25 Sep 1953, Neumann s.n. (W) .

Japan. Honshu: Tochigi, Utsunomiya Agricultural College, Japan, 1935, Kagawa s.n. (K) Kyoto, Koyama , Chitose , Chitose-cho , Kameoka-shi , 12 Sep 2010, Tsugaru et al. 7604 (MO) .

Lesotho. Maseru airfield escarpment, Lesotho , 10 Dec 1969, Without collector 348 (K); Maseru Ekp Stn , 3 Mar 1970, Without collector 650 (K).

New Zealand. North Island: Auckland, Tawharanui Regional Park , 14 Jan 2012, Salter & Duff s.n. (AK); Northland, Te Arai Sanctuary, 27 Jan 1995, Wright 12532 (AK) ; South Island: Tasman, Collingwood, 1 km W on Cape Farewell rd, 13 Mar 2006, Brummitt 21567 (K) .

Portugal. Azores: Faial, Horta , 27 Sep 1970, Brooke 11376 (BM); Faial, Capelo, 1 Dec 1971, Goncalves 374 (BM); Faial between Pedro Miguel and Espalhafatos, 15 Sep 2001, Henderson et al. 98 (AZU, BM) ; Centro: Vila Nova de Barquinha, Ribatejo , 16 Jul 1963, Rainha 6177 (W) ; Madeira: Between Monte and Funchal , 11 Sep 1984, Davis 70402 (BM) ; Norte: Amarante, Marcos de Canavezes, Douro Litoral , 6 Jul 1960, Pinto da Silva et al. 6754 (W) .

South Africa. Eastern Cape: Old Town Quarry, Grahamstown , 20 Nov 1972, Bayliss 5292 (A, BH, MO); Belmont Valley , Albany Dist, 1 Sep 1974, Bayliss 6785 (K, MO); Humansdorp, Distr. Humansdorp, Tzitzikama Park, 2 Feb 1966, Liebenberg 7909 (K) ; Gauteng: Germiston District, Dowerglen , 22 Oct 1992, Balkwill 7163 (MO); Pretoria, Johannesburgh, Taamlik volop, 2627BB grid ref, Oct 1976, Liebenberg 8568 (K, MO) ; KwaZulu-Natal: Pretoria, Greytown, Natal , 11 Feb 1939, Galpin 14832 (K); Underberg, 2929 CB Sani Pass, Undeberg Distr. , 17 Feb 1982, Hilliard & Burtt 15537 (K); Nottingham rd, Natal, Mar 1939, McClean 869 (K, MO) ; Mpumalanga: Middelburgh District , just outside Middelburgh, 26 Jan 1995, Balkwill 9130 (MO) ; Western Cape: 3323 Willowmore DC, 28 Dec 1982, Goldblatt 6780 (MO) .

Spain. Cantabria: Santander, rd to Pechon , 31 Jul 1972, Brenan 12271 (BM, K) .

Sweden. Götaland: Västra Götaland, Göteborg, Backa prope Brunnsbo , Aug 1938, Blom s.n. (BM); Västra Götaland, Agnesbergs kvarn, 30 Sep 1938, Blom s.n. (K, W) .

Switzerland. Ticino: Locarno, bank of Maggia river , 17 Sep 2000, Brummit 20476 (K) .

United Kingdom. Channel Isles: Guernsey, nr entrance to Mont Cuet, Nov 2001, Dupree s.n. (BM); Guernsey, 6 Sep 1994, McClintock & Ryan s.n. (BM); Guernsey, St. Sampsons , 23 Jul 1968, Simpson 68010 (BM) ; England: Greater London, Victoria Park , 4 Sep 2008, Atchison 2 (BM); Worcestershire, Charlton, 25 Aug 1959, Pannister 983 (BM); Cornwall, Bude, Aug 1925, Thurston s.n. (K) ; Wales: Vale of Glamorgan, Barry Docks , 12 Sep 1935, Brenan & Sandwith 1449 (BM); Cardiff, Barry Docks, 12 Sep 1935, Sandwith & Brenan s.n. (K) .

Figures

Figure 10. Solanum chenopodioides Lam. A Habit B Detail of adaxial leaf surface C Detail of abaxial leaf surface D Opening bud E Dissected flower F Fruiting branch G Detail of infructescence H Maturing fruit I Fully mature fruit (A-E Fox s. n.; F-I Hieronymus s. n.). Drawing by R. Wise.

Figure 11. Solanum chenopodioides Lam A Habit B Buds C Flowers at full anthesis D Fully mature matte black fruits with appressed calyx lobes (A-D Nijmegen acc. A 14750051). Photos by S. Knapp and G. van der Weerden.

Figure 12. Distribution of Solanum chenopodioides Lam in its non-native range in the Old World.