A revision of the Dulcamaroid Clade of Solanum L. (Solanaceae)

Abstract

The Dulcamaroid clade of Solanum contains 45 species of mostly vining or weakly scandent species, including the common circumboreal weed Solanum dulcamara L. The group comprises members of the previously recognised infrageneric groupings sect. Andropedas Rusby, sect. Californisolanum A. Child, sect. Dulcamara (Moench) Dumort., sect. Holophylla (G.Don) Walp., sect. Jasminosolanum (Bitter) Seithe, sect.Lysiphellos (Bitter) Seithe, subsect. Nitidum A.Child and sect. Subdulcamara Dunal. These infrageneric groups are not monophyletic as traditionally recognised, and the complex history of the classification of the dulcamaroid solanums is reviewed. Many of the species in the clade are quite variable morphologically; plants are shrubs, herbaceous vines or woody canopy lianas, and habits can vary between these states in a single locality. Variation in leaf shape and pubescence density and type is also extreme and has lead to the description of many minor morphological variants as distinct species. The flowers of members of the group are generally very showy, and several species (e.g., Solanum crispum Ruiz & Pav., Solanum laxum Spreng., Solanum seaforthianum Andrews) are popular ornamental plants that have occasionally escaped from cultivation and become naturalised. The clade is here divided into five morphologically and geographically delimited species groups to facilitate further study. One new species from southern Ecuador, Solanum agnoston S.Knapp sp. nov., is described here. Full descriptions and synonymies (including designations of lectotypes or neotypes), preliminary conservation assessments, illustrations, distribution maps, and an extensive list of localities are provided for all species.

Keywords: Asia; Solanum; South America; USA; classification; monograph; new species; taxonomy; vines.

Figure 1.

Habit of members of the Dulcamaroid clade. A Twining petioles that aid in climbing (Solanum laxum, cultivated in London UK) B Solanum angustifidum (Barboza et al. 3489) as a lax shrub on a fence in Argentina C Erect shrub of Solanum nitidum (Nee et al. 51755, Cochabamba, Bolivia).

Figure 2.

Leaf variation in members of the Dulcamaroid clade. A Leaf variation along a single short stem, Solanum salicifolium (Barboza et al. 3467, Catamarca, Argentina) B Thick leathery leaves of Solanum macbridei (Nee & Solomon 30182, La Paz, Bolivia) C Uneven leaf lobing in Solanum dulcamara (Knapp IM-10102, Tuscany, Italy) D Variable membranous leaves of Solanum lyratum (Knapp et al. 10139, Jiangxi, China).

Figure 3.

Trichome types found in members of the Dulcamaroid clade. A Loose dendritic B Simple glandular C Echinoid D Furcate.

Figure 4.

Inflorescences of members of the Dulcamaroid clade. A Open cyme of Solanum dulcamaroides (cultivated in Nijmegen, The Netherlands A44750197) B Grouped flowers on platforms of Solanum aligerum (Knapp et al. 10436, Cusco, Peru) C Pedicel sleeve of Solanum nitidum (Knapp et al. 10222, Huancavelica, Peru) D Contrasting pedicel colour in Solanum valdiviense (cultivated in Royal Botanic Garden, Edinburgh, UK, Knapp IM-10105).

Figure 5.

Flowers of members of the Dulcamaroid clade. A Solanum lyratum (Knapp et al. 10142, Hubei, China) B Solanum nitidum (Knapp et al. 10222, Huancavelica, Peru) C Solanum endoadenium (Barboza et al. 3476, Catamarca, Argentina) D Solanum dulcamara (Kent, UK) E Solanum laxum (cultivated in London, UK) F Solanum uncinellum (cultivated in Nijmegen, The Netherlands 994750113).

Figure 6.

Fruits of members of the Dulcamaroid clade. A Solanum pittosporifolium (Knapp et al. 10136, Jiangxi, China) B Solanum salicifolium (Barboza et al. 3467, Catamarca, Argentina) C Solanum storkii (Knapp & Monro 10053, Bocas del Toro, Panama) D Solanum angustifidum (Barboza et al. 3489, Argentina) F Solanum nitidum (Knapp et al. 10136, Cusco, Peru).

Figure 7.

Habitats of members of the Dulcamaroid clade. A Gravel shingle at Rye Harbour Nature Reserve, coastal Sussex, UK (with Solanum dulcamara) B Dry forest grassland chaco habitat in Formosa, Argentina (with Solanum amygdalifolium) C Ceja de selva (near timberline) in Andean Peru (Cusco above Ollantaytambu) D High elevation dunes in Catamarca, Argentina (with Solanum endoadenium) E Eastern Andean slopes of Peru, premontane cloud forest F Rocky river course in the Lushan Mountains of Jiangxi, China.

Figure 8.

Solanum agnoston S.Knapp. (A, B drawn from Holm-Nielsen et al. 5115 C drawn from Jaramillo et al. 8832). Illustration by Bobbi Angell.

Figure 9.

Distribution of Solanum agnoston S.Knapp

Figure 10.

Solanum aligerum Schltdl. (A drawn from Martinez S. 4741 B–D drawn from Torres B. 2022 E drawn from Nee 26870). Illustration by Bobbi Angell.

Figure 11.

Distribution of Solanum aligerum Schltdl.

Figure 12.

Solanum alphonsei Dunal. (A–H drawn from Anon. s.n., Mar 1858, BM). Illustration by Bobbi Angell.

Figure 13.

Distribution of Solanum alphonsei Dunal.

Figure 14.

Solanum amygdalifolium Steud. (A, C–E drawn from Nee 52046 B drawn from Mendoza 102). Illustration by Bobbi Angell.

Figure 15.

Distribution of Solanum amygdalifolium Steud.

Figure 16.

Solanum angustifidum Bitter. (A drawn from Tressens et al. 560 B–E drawn from Pedersen 7150 F drawn from Cristóbal et al. 1618). Illustration by Bobbi Angell.

Figure 17.

Distribution of Solanum angustifidum Bitter.

Figure 18.

Solanum aspersum S. Knapp. (A–C drawn from MacDougal et al. 4251 D–E from Zak 1857A). Originally published in Knapp (2010). Illustration by Bobbi Angell.

Figure 19.

Distribution of Solanum aspersum S.Knapp

Figure 20.

Solanum aureum Dunal. (A drawn from Juncosa 2335, NY B drawn from Zak 1845 C–G drawn from Rose 22963 H drawn from Cerón et al. 11842). Illustration by Bobbi Angell.

Figure 21.

Distribution of Solanum aureum Dunal.

Figure 22.

Solanum boldoense Dunal & A.DC. (A–G drawn from Clark 10597 and J. Clark photographs taken in the field H drawn from Wright 381, NY). Illustration by Bobbi Angell.

Figure 23.

Distribution of Solanum boldoense Dunal & A.DC.

Figure 24.

Solanum calileguae Cabrera.(A–D drawn from Nee & Bohs 50809 E drawn from Nee & Bohs 50768). Illustration by Bobbi Angell.

Figure 25.

Distribution of Solanum calileguae Cabrera.

Figure 26.

Solanum coalitum S. Knapp. (A, B drawn from Jorgensen 2188 C D drawn from G. Lewis photographs of Lewis 3179). Illustration by Bobbi Angell.

Figure 27.

Distribution of Solanum coalitum S.Knapp.

Figure 28.

Solanum crispum Ruiz & Pav. (A drawn from Taylor 10235 B drawn from Nee 54654 C drawn from Landrum 8216 D drawn from Biese 78 E–H drawn from Landrum 4459). Illustration by Bobbi Angell.

Figure 29.

Distribution of Solanum crispum Ruiz & Pav.

Figure 30.

Lectotype of Solanum ligustrum Lodd. (Loddiges 1833: tab. 1963). Reproduced with permission of the Natural History Museum Botany Library.

Figure 31.

Solanum cutervanum Zahlbr. (drawn from Hutchison & von Bismarck 6571). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 32.

Distribution of Solanum cutervanum Zahlbr.

Figure 33.

Solanum dichroandrum Dunal. (A–F drawn from Riina et al. 784 G–I drawn from Killip & Smith 17916). Illustration by Bobbi Angell.

Figure 34.

Distribution of Solanumdichroandrum Dunal.

Figure 35.

Solanum dulcamara L. (All drawn from live plants in Battleboro, Vermont, USA). Illustration by Bobbi Angell.

Figure 36.

Distribution of Solanum dulcamara L.

Figure 37.

“Dulcis amara” from Hortus Eystettensis (Besler 1613). The centre plant is clearly Nigella (Ranunculaceae), but was described as a variety of Solanum dulcamara by David Don. Reproduced with permission of the Natural History Museum Botany Library.

Figure 38.

Solanum dulcamaroides Poir. (A drawn from Saunders 8220 B drawn from Nee 23837 C drawn from Nee 23735 D–F drawn from Cortés 29 G drawn from Lopez 340). Illustration by Bobbi Angell.

Figure 39.

Distribution of Solanum dulcamaroides Poir.

Figure 40.

Lectotype of Solanum dulcamaroides Poir. (Torner Collection plate 6331.1503). Reproduced with permission of the Hunt Institute for Botanical Documentation, Carnegie Mellon University, Pittsburgh, PA. Torner Collection of Sessé and Mociño Biological Illustrations. Rights reserved.

Figure 41.

Solanum endoadenium Bitter. (A, C–G drawn from Hunziker et al. 25550 B Legname & Vervoorst 154). Illustration by Bobbi Angell.

Figure 42.

Distribution of Solanum endoadenium Bitter.

Figure 43.

Solanum flaccidum Vell. (A–D drawn from Nee & Bohs 50809 E drawn from Nee & Bohs 50768). Illustration by Bobbi Angell.

Figure 44.

Distribution of Solanum flaccidum Vell.

Figure 45.

Lectotype of Solanum flaccidum Vell. (Vellozo 1831: tab. 115). Reproduced with permission of the Natural History Museum Botany Library.

Figure 46.

Lectotype of Solanum triphyllum Vell. (Vellozo 1831: tab. 120). Reproduced with permission of the Natural History Museum Botany Library.

Figure 47.

Solanum imbaburense S. Knapp. (A–C drawn from Øllgaard & Balslev 8567). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 48.

Distribution of Solanum imbaburense S.Knapp

Figure 49.

Solanum inodorum Vell. (A–F drawn from Hatschbach 26839 G drawn from Reitz & Klein 5290). Illustration by Bobbi Angell.

Figure 50.

Distribution of Solanum inodorum Vell.

Figure 51.

Lectotype of Solanum inodorum Vell. (Vellozo 1831: tab. 107). Reproduced with permission of the Natural History Museum Botany Library.

Figure 52.

Solanum kulliwaita S.Knapp. (A–E drawn from Valenzuela 3163 F–G drawn from Galiano 6137). Illustration by Bobbi Angell.

Figure 53.

Distribution of Solanum kulliwaita S.Knapp.

Figure 54.

Solanum laxum Spreng. (A drawn from Nee 36730 and M.Nee photographs of plant in the field B drawn from Bohs & Nee 3191 C drawn from Hatschbach 22971 D drawn from Steyermark 53983 E–I drawn from plants cultivated in London). Illustration by Bobbi Angell.

Figure 55.

Distribution of Solanum laxum Spreng.

Figure 56.

Lectotype of Solanum jasminoides Paxt. (Paxton 1841: tab. 5) Reproduced with permission of the Natural History Museum Botany Library.

Figure 57.

Solanum leiophyllum Benth. (A–C drawn from Hartweg 812). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library.

Figure 58.

Distribution of Solanum leiophyllum Benth.

Figure 59.

Solanum luculentum S.Knapp. (A–B drawn from Nee & Callejas 32546 C–F from Steyermark et al. 127855, G from Steyermark & Dunsterville 100777 H from Killip & Smith 15952). Originally published in Knapp (2010). Illustration by Bobbi Angell.

Figure 60.

Distribution of Solanum luculentum S.Knapp.

Figure 61.

Solanum lyratum Thunb. (A–D drawn from Smith 6432 and Knapp 10142 E–G drawn from Peixing Tan 57179 G drawn from Smith 2265 H drawn from Junsheng Ying 0907). Illustration by Bobbi Angell.

Figure 62.

Distribution of Solanum lyratum Thunb.

Figure 63.

Solanum macbridei Hunz. & Lallana. (A–C drawn from Solomon & Stein 11660). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 64.

Distribution of Solanum macbridei Hunz. & Lallana.

Figure 65.

Solanum muenscheri Standl. & Steyerm. (A–B drawn from Steyermark 35633). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 66.

Distribution of Solanum muenscheri Standl. & Steyerm.

Figure 67.

Solanum nitidum Ruiz & Pav. (A–B drawn from D.N. Smith 1622). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 68.

Distribution of Solanum nitidum Ruiz & Pav.

Figure 69.

Solanum odoriferum Vell. (A–E drawn from Hatschbach 20204 F–G drawn from Reitz & Klein 6343). Illustration by Bobbi Angell.

Figure 70.

Distribution of Solanum odoriferum Vell.

Figure 71.

Lectotype of Solanum odoriferum Vell. (Vellozo 1831: tab. 108) Reproduced with permission of the Natural History Museum Botany Library.

Figure 72.

Solanum pittosporifolium Hemsl. (A drawn from Li 96079 B–C drawn from Wan et al. 1824 D–F drawn from Zhou 060 G drawn from photographs of Knapp 10136). Illustration by Bobbi Angell.

Figure 73.

Distribution of Solanumpittosporifolium Hemsl.

Figure 74.

Solanum pubigerum Dunal. (A–E drawn from Reveal et al. 4230 F–G drawn from de Avila 178). Illustration by Bobbi Angell.

Figure 75.

Distribution of Solanumpubigerum Dunal.

Figure 76.

Lectotype of Solanum pubigerum Dunal (Dunal 1813: tab. 6). Reproduced with permission of the Natural History Museum Botany Library.

Figure 77.

Lectotype of Solanum leptanthum Dunal (Torner Collection plate 6331.0673). Reproduced with permission of the Hunt Institute for Botanical Documentation, Carnegie Mellon University, Pittsburgh, PA. Torner Collection of Sessé and Mociño Biological Illustrations. Rights reserved.

Figure 78.

Solanum pyrifolium Lam. (A–E drawn from Colella 1361 and M. Nee unvouchered photographs from Hispaniola F drawn from Gastony et al. 525). Illustration by Bobbi Angell.

Figure 79.

Distribution of Solanumpyrifolium Lam.

Figure 80.

Solanum ruizii S. Knapp. (A–B drawn from Macbride 4351). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 81.

Distribution of Solanum ruizii S.Knapp.

Figure 82.

Solanum salicifolium Phil. (A–F drawn from Varela 633 G–J drawn from Keisling 7929 K–L drawn from Kuntze s.n., Dec 1891 M drawn from King 151 N drawn from Hieronymus s.n., coll. 1878). Illustration by Bobbi Angell.

Figure 83.

Distribution of Solanum salicifolium Phil.

Figure 84.

Solanum sanchez-vegae S. Knapp. (A–F drawn from Smith & Sanchez-Vega 7524 G from Hutchison et al. 5738). Originally published in Knapp (2010). Illustration by Bobbi Angell.

Figure 85.

Distribution of Solanum sanchez-vegae S.Knapp.

Figure 86.

Solanum seaforthianum Andrews. (A drawn from Baker 10374 B H drawn from Thompson 947 C drawn from Hatschbach 60388 D drawn from Renderos 517; E-g drawn from McVaugh 20220). Illustration by Bobbi Angell.

Figure 87.

Distribution of Solanum seaforthianum Andrews.

Figure 88.

Lectotype of Solanum seaforthianum Andrews (Andrews 1808: tab. 504) Reproduced with permission of the Natural History Museum Botany Library.

Figure 89.

Solanum septumlobum Bunge. (A, E–G drawn from Smith 7514 B drawn from Smith 6456 C drawn from Shanxi Team 1627 D [leaf variation] from Li 930033b in addition to those cited). Illustration by Bobbi Angell.

Figure 90.

Distribution of Solanum septumlobum Bunge.

Figure 91.

Solanum sousae S. Knapp. (A–D drawn from Ventura 2212, E from Maya J. 3938). Originally published in Knapp (2010). Illustration by Bobbi Angell.

Figure 92.

Distribution of Solanum sousae S.Knapp.

Figure 93.

Solanum stenophyllum Dunal. (A–B drawn from Pennell 3082). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 94.

Distribution of Solanum stenophyllum Dunal.

Figure 95.

Solanum storkii C.V.Morton & Standl. (A–B drawn from Heiser 3489). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 96.

Distribution of Solanum storkii C.V.Morton & Standl.

Figure 97.

Solanum triquetrum Cav. (A drawn from Lindheimer 1044 B drawn from Chiang 7857 C drawn from Waterfall 6278 D drawn from Pringle 153 E–H drawn from Burr 452). Illustration by Bobbi Angell.

Figure 98.

Distribution of Solanum triquetrum Cav.

Figure 99.

Solanum umbelliferum Eschsch. (A drawn from Joyal & Mehlmar 1272 B drawn from Halse 6149 C drawn from Twisselman 3423 D drawn from Anderson 2886 E drawn from Blakley 3954 F drawn from Chamberlain s.n. G–J drawn from Williams 68-3-10). Illustration by Bobbi Angell.

Figure 100.

Distribution of Solanum umbelliferum Eschsch. and Solanum wallacei (A. Gray) Parish (inset)

Figure 101.

Solanum uncinellum Lindl. (A–F drawn from Hammel et al. 21289 G drawn from Nee 37364 H drawn from Nee 36071 I drawn from L.B.B. 9830). Illustration by Bobbi Angell.

Figure 102.

Distribution of Solanum uncinellum Lindl.

Figure 103.

Plate accompanying the original description of Solanum uncinellum Lindl. clearly showing the unequal anthers and narrow petals typical for this species (Lindley 1840: tab. 15). Reproduced with permission of the Natural History Museum Botany Library.

Figure 104.

Solanum valdiviense Dunal. (A–G drawn from Taylor et al. 10282 H drawn from Taylor & Taylor 10843 I drawn from Werdermann 323). Illustration by Bobbi Angell.

Figure 105.

Distribution of Solanum valdiviense Dunal.

Figure 106.

Solanum viscosissimum Sendtn. (A, G, I drawn from Ratter 3430 B drawn from Ribas et al. 1154 C, H drawn from Irwin et al. 11355 D drawn from Irwin et al. 18165b E, F drawn from Irwin 6221). Illustration by Bobbi Angell.

Figure 107.

Distribution of Solanumviscosissimum Sendtn.

Figure 108.

Solanum wallacei (A. Gray) Parish. (A, C–F drawn from Moran 687 B drawn from Trask s.n., coll. May 1896 G drawn from Walker 1433). Illustration by Bobbi Angell.