Solanum salicifolium Phil., Anal. Univ. Chile 36: 195. 1870.

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

50. Solanum salicifolium Phil., Anal. Univ. Chile 36: 195. 1870.

Figs 2H , 3F , 152 , 153

Solanum incisum Griseb., Abh. Königl. Ges. Wiss. Göttingen 24: 251. 1879. Type. Argentina. Córdoba: Sierra de Achala, 24-25 Mar 1874, G. Hieronymus 220 (lectotype, designated by Morton 1976, pg. 99: GOET [GOET003582]; isolectotypes: B, destroyed [F neg. 2779], CORD [CORD00006112]).

Solanum sericeum Ruiz & Pav. var. strigillosum Griseb., Abh. Königl. Ges. Wiss. Göttingen 24: 252. 1879. Type. Argentina. Córdoba: Dpto. Las Minas, Cerro de Orcosu [Achala in protologue], 20 Feb 1876, G. Hieronymus 812 (holotype: GOET [GOET003580]; isotypes: CORD [CORD00006115], US [00027795, acc. # 2678278]).

Solanum tenuisectum Kuntze, Revis. Gen. Pl. 3(2): 227. 1898. Type. Argentina. "western Pampas, 34 degrees", Jan 1892, O. Kuntze s.n. (lectotype, designated by Knapp 2013, pg. 238: NY [00172207]; isolectotype: NY [00172206]).

Solanum incisum Griseb. var. septatopilosum C.V. Morton, Revis. Argentine Sp. Solanum 100. 1976. Type. Argentina. Catamarca: Dpto. Belén, Pozo de Piedra, 1,900 m, 25-31 Jan 1952, H. Sleumer & F. Vervoorst 2375 (holotype: US [01049780, acc. #2173088]; isotype: LIL).

Solanum crebrum C.V.Morton & L.B.Sm., Revis. Argentine Sp. Solanum 80. 1976. Type. Argentina. Catamarca: Dpto. Andalgalá, Alto de las Juntas y alrededores, 1-16 Jan 1952, 2,700-2,830 m, H. Sleumer 2166 (holotype: US [00027530, acc. # 2168362]; isotypes: CORD [CORD00012840], G [G00357861], LIL [LIL-394778]).

Solanum incisum Griseb. var. tenuisectum (Kuntze) C.V. Morton, Revis. Argentine Sp. Solanum 100. 1976. Type. Based on Solanum tenuisectum Kuntze.

Solanum vervoorstii C.V.Morton, Revis. Argentine Sp. Solanum 128. 1976. Type. Argentina. Catamarca: Dpto. Belén, Quebrada de los Potrerillos above El Rodeo, Granadillas, 26 Jan 1952, 2,700-2,830 m, H. Sleumer & F. Vervoorst 2481 (holotype: US [00027846, acc. # 2168145]; isotypes: G, LIL [acc. # 394789]).

Solanum restrictum C.V.Morton, Revis. Argentine Sp. Solanum 128. 1976. Type. Argentina. Córdoba: Dpto. Punilla, Estancia El Rosario, east of La Cumbre, Sierra de Córdoba, 20 Mar 1943, H.H. Bartlett 20171 (holotype: US [00027775, acc. # 2320061]).

Solanum ratum C.V.Morton, Revis. Argentine Sp. Solanum 130. 1976. Type. Argentina. Córdoba: Dpto. Punilla, El Durazno, 18 Mar 1944, C.A. O’Donell & J.M. Rodriguez V. 805 (holotype: A [00077745]; isotype: LIL [acc. # 97232]).

Type.

Argentina. Mendoza: Villavicencio, R.A. Philippi s.n. (lectotype, designated by Knapp 2013, pg. 238: SI [acc. # 26577]; isolectotypes: G [G00070190, F neg. 23156], SGO [SGO acc. # 42739, acc. # 55501], W [acc. # 0001341]) .

Description.

Suffrutescent herbs to small shrubs, 0.5-1.5 m high, arising from a woody rootstock. Stems slightly angled when young, sparsely to densely pubescent with simple uniseriate trichomes to 0.5 mm long, these strongly antrorse and all appressed to stem, occasionally (collections from Famatina in La Rioja Province, Argentina) more floccose, the trichome base enlarged and slightly bulbous; new growth glabrous or densely pubescent with simple white trichomes like those of the stems. Bark of older stems yellowish grey, glabrescent. Sympodial units difoliate to plurifoliate, if difoliate, the leaves not geminate. Leaves simple to variably pinnatifid, the blades 2.5-10 cm long, 1-7 cm wide, more or less lanceolate to narrowly elliptic in outline, widest at the middle, membranous to chartaceous, concolorous or slightly discolorous; adaxial surfaces glabrous or with scattered simple uniseriate trichomes at the base and along the veins, these all appressed and pointing distally; abaxial surfaces glabrous to uniformly pubescent with appressed and ascending simple uniseriate trichomes <0.2 mm long; principal veins 10-20 pairs, drying yellowish grey; base attenuate, winged along the stem; margins entire to 3-5-lobed, the lobes 0.5-3.5 cm long, 0.2-0.7 cm wide, incised to the midrib or very shallowly, in the basal part of the leaf; apex acute to acuminate; petioles very short to apparently absent, sparsely pubescent with ascending appressed trichomes on all surfaces like those of the stems. Inflorescences internodal, occasionally opposite the leaves, unbranched or forked, 1-2.5 cm long, with 4-10 flowers in a pseudoumbel, glabrous to pubescent with ascending appressed simple uniseriate trichomes like those of the stems and leaves; peduncle 1-2.2 cm long; pedicels 0.7-1.2 cm long, filiform, ca. 0.5 mm in diameter, nodding at anthesis, pubescent like the rest of the inflorescence, articulated at the base in a very small sleeve; pedicel scars tightly packed at the tip of the inflorescence on a small platform. Buds ellipsoid to fusiform and elongate, the corolla strongly exserted from the calyx tube before anthesis. Flowers 5-merous, cosexual (hermaphroditic). Calyx tube 1-1.5 mm long, conical, the lobes 2.5-3 mm long, long-triangular to lanceolate, glabrous to pubescent with appressed white simple trichomes like those of the stems and leaves. Corolla 1-1.6 cm in diameter, violet or white, often with a green or yellowish green eye, stellate, lobed nearly to the base, the lobes 6-8 mm long, 3-4 mm wide, strongly reflexed at anthesis, densely and uniformly pubescent abaxially with minute simple uniseriate trichomes <0.1 mm long, glabrous adaxially. Stamens equal; filament tube ca. 0.5 mm long; free portion of the filaments 0.5-1 mm long, densely pubescent adaxially with tangled simple trichomes 0.5-1 mm long; anthers (3-)5-5.5 mm long, ca. 1 mm wide, ellipsoid, loosely connivent to occasionally somewhat spreading, poricidal at the tips, the pores lengthening to slits with age. Ovary glabrous; style 9-11 mm long, straight, exserted beyond the anther cone, glabrous or pubescent with weak simple trichomes in the basal 2/3; stigma capitate, the surface minutely papillose. Fruit a globose berry, 0.5-0.7 cm in diameter, purple or reddish purple when ripe, the pericarp thin and somewhat shiny, opaque, glabrous; fruiting pedicels 1-1.5 cm long, ca. 1 mm in diameter at base and apex, not particularly woody, pendent from weight of fruit, not persistent. Seeds 20-50 per berry, ca. 1.5 mm long, ca. 1.5 mm wide, flattened reniform, yellowish brown, the surfaces minutely pitted, the testal cells rectangular. Stone cells ca. 10 per berry, 0.7-1 mm in diameter. Chromosome number: n = 12 ( Moscone 1992, vouchers Ambrosetti & Moscone 1477, Del Vitto & Moscone 852; Hunziker et al. 24876, 24882, 25043, Moscone et al. 91, 92 as S. incisum ; Moyetta et al. 2013, vouchers Barboza et al. 3488, 3158, Chiarini et al. 818, 794).

Distribution

(Fig. 154 ). Solanum salicifolium occurs on the eastern slopes and foothills of the Andes in western Argentina (Provs. Catamarca, Córdoba, Entre Ríos, Jujuy, La Pampa, La Rioja, Mendoza, Salta, San Juan, San Luis, Tucumán) and Paraguay (Dept. Presidente Hayes). Nineteenth century collections labelled as being collected in “Chile” are almost certainly from adjacent Argentina near Mendoza (e.g., Cuming s.n., Gillies 32, Née s.n.).

Ecology and habitat.

Solanum salicifolium occupies a wide range of dry forested and open habitats, from Chaco woodlands to puna areas above treeline, often growing amongst rocks in grazed areas or on roadsides, from 600 to 4,100 m elevation.

Common names and uses.

Argentina. Córdoba: yerba mora (Kurtz 8324). No uses recorded.

Preliminary conservation status

( IUCN 2022). Least Concern [LC]. EOO = 1,063,580 km2 [LC]; AOO = 896 km2 [VU]. Solanum salicifolium is common where it occurs, is widely distributed geographically and occurs in a number of different habitats. It is found in protected areas in the Argentine Provinces of Mendoza (e.g., Puente del Inca, Parque Provincial Aconcagua) and Córdoba (e.g., Pampa de Achala).

Discussion.

Knapp (2013) treated S. salicifolium as a member of the Dulcamaroid clade due to its possession of a small pedicel sleeve (swollen insertion point), a characteristic of the dulcamaroids. Molecular sequence data, however, show that S. salicifolium belongs to the Morelloid clade ( Särkinen et al. 2015b; Gagnon et al. 2022). Possession of stone cells in the berries, noted as unusual in the dulcamaroids by Knapp (2013) also points to its morelloid affinities. Solanum salicifolium is extremely (almost incredibly) variable in leaf shape (see Figs 2H , 152D, E , 153 A, B ), ranging from simple and linear (the type of S. salicifolium ) to deeply pinnatifid with very narrow lobes (the type of S. tenuisectum ). This is an extreme of variation in leaf shape and has led to considerable confusion over the identity and synonymy of this species. Morton (1976) suggested that leaves with a single pair of lobes at the base might be a late season growth form, but we have seen all leaf shapes on a single plant.

The pinnatifid leaves of S. salicifolium are somewhat morphologically similar to those of members of the Radicans clade ( S. corymbosum , S. palitans , S. radicans and S. tripartitum ). These taxa have pedicels that are flush with the inflorescence axis, rather than inserted into a small sleeve, and the flowers are spaced along the inflorescence axis rather than being clustered at the tip on a small platform. The flowers of S. salicifolium are much larger than those of members of the Radicans clade, with anthers 3-5.5 mm long versus 1-2 mm long.

For details of typification of the many synonyms of S. salicifolium see Knapp (2013).

Figures

Figure 2. Representative habits and leaves of South American morelloids A prostrate annual herbs (S. weddellii) B large lax shrubs (S. aloysiifolium) C roots forming along a creeping stem (S. juninense) D spinose processes on stems of many species (S. huayavillense) E glandular trichomes found in some members of the clade (S. glandulosipilosum) F dendritic / branched trichomes found in S. pallidum G regularly 3 - lobed leaves in S. palitans H highly variable leaves along a single stem in S. salicifolium (A Saerkinen et al. 4038 B Barboza et al. 3505 C Saerkinen et al. 4754 D Barboza et al. 3536 E Barboza et al. 3520 F Saerkinen et al. 4010 G Atchison & Gagnon 25 H Barboza et al. 3473). Photos by S. Knapp, G. Atchison, and T. Saerkinen.

Figure 3. Representative flowers of South American morelloids A campanulate purple corollas in forked internodal inflorescences in S. fiebrigii B pentagonal white corollas in S. annuum C broadly stellate purple corollas with long-exerted styles in S. pentlandii D broadly stellate white corollas with slightly exerted globose stigmas in S. radicans E deeply stellate pale yellow corollas in S. huayavillense F deeply stellate purple corollas with dark central eye colouration in S. salicifolium G bumblebee visiting and buzzing the anther cone in S. cochabambense H variation in corolla shape, size and colouration within a single individual of S. cochabambense (A Barboza et al. 3548 B Barboza et al. 3495 C Knapp et al. 10248 D Knapp et al. 10277 E Barboza et al. 3531 F Chiarini et al. 819 G Saerkinen et al. 4036 H Knapp et al. 10669). Photos by S. Knapp and T. Saerkinen.

Figure 152. Solanum salicifolium A, B flowering habit C fruiting habit D, E sterile habit showing leaf shape variation F inflorescence in bud G flower bud H, I flower J, K stamens L, M gynoecium N maturing fruit (A, I, K, M Kiesling et al. 7929 B, F-H, J, L Varela 633 C, N Kuntze s. n., Dec 1891 D King 151 E Hieronymus s. n., collected in 1878). Illustration by B. Angell. Previously published in Knapp (2013: 240).

Figure 153. Solanum salicifolium A habit with less divided leaves B habit with more divided leaves C flowers and buds D flowers at anthesis (A Barboza et al. 3465 B, D Barboza et al. 3494 C Barboza et al. 3473). Photos S. Knapp.

Figure 154. Distribution map of Solanum salicifolium.