Solanum radicans L.f., Dec. Pl. Horti Upsal. 1. Apr-Jul 1762.

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

46. Solanum radicans L.f., Dec. Pl. Horti Upsal. 1. Apr-Jul 1762.

Figs 3D , 140 , 141

Witheringia ruderalis J. Rémy, Fl. Chil. [Gay] 5: 69. 1849. Type. Chile. Región IV (Coquimbo): Coquimbo, C. Gay 297 (neotype, designated here: P [P00370543]; isolectotype: P [P00370544]).

Solanum ruderale (J. Rémy) F.Phil., Cat. Pl. Vasc. Chil. 229. 1881. Type. Based on Witheringia ruderale J. Rémy.

Type.

Cultivated in Uppsala , from Peru, Anon. s.n. (lectotype, designated by Knapp in Jarvis 2007, pg. 861: LINN [LINN 248.9]) .

Description.

Creeping herbs to sprawling subshrubs, 0.2-0.75 m high, branches occasionally rooting at the lower nodes. Stems strongly angled to winged from the decurrent leaf bases, with occasional spinescent process along the angles, sparsely pubescent with white eglandular 2-3-celled uniseriate trichomes ca. 0.5 mm long, glabrescent; new growth glabrous to sparsely pubescent with a few scattered white eglandular trichomes like those of the stems, the new leaves densely papillate. Sympodial units difoliate, the leaves not geminate. Leaves simple and deeply 5-lobed, the blades 2.5-14 cm long, 2.5-6 cm wide, elliptic to ovate in outline, widest at the middle or in the lower half, chartaceous, concolorous; adaxial surfaces glabrous or with a few scattered white eglandular simple uniseriate trichomes to 0.5 mm long along the midrib and principal veins, the midrib raised above; abaxial surfaces glabrous or with a few scattered white eglandular simple uniseriate trichomes to 0.5 mm long along the midrib and principal veins; principal veins 2-3 pairs, the midrib raised above; base attenuate onto the stem; margins deeply (3)5-lobed nearly to the midrib, the lobes 3-5 cm long, ca. 2 cm wide, widest in the distal third, asymmetrically elliptic, narrowed near the base, the terminal lobe the largest, occasionally the lateral lobes with minute secondary lobes, the sinuses 3/4 or more of the distance to the midrib, often sparsely ciliate; petiole 0-1 cm long, winged for most of its length. Inflorescences internodal to almost opposite the leaves, usually unbranched, occasionally forked, 2-7 cm long, with 10-20 flowers, sparsely to moderately pubescent with white simple uniseriate trichomes like those of the stems; peduncle 1-3 cm long; pedicels 0.5-1 cm long, 0.4-0.5 mm in diameter at the base, 0.4-0.6 mm in diameter at the apex, with a few scattered white simple trichomes near the base, distally glabrous, articulated at the base; pedicel scars irregularly spaced 1.5-2.5 mm apart. Buds globose, purple-tinged, the corolla halfway to strongly exserted from the calyx before anthesis. Flowers 5-merous, cosexual (hermaphroditic). Calyx tube 1.5-2 mm long, cup-shaped and abruptly narrowing to the pedicel, the lobes 0.75-2 mm long, 0.5-0.9 mm wide, triangular to long-triangular, slightly fleshy, glabrous. Corolla 1-1.2 cm in diameter, rotate-stellate, pale violet to purple, with a greenish yellow central star, lobed ca. halfway to the base, the lobes 2.5-4 mm long, 3-4 mm wide, spreading at anthesis, glabrous adaxially and abaxially, except for the densely papillate lobe tips. Stamens equal; filament tube minute; free portion of the filaments 0.3-0.4 mm long, pubescent with tangled white simple uniseriate trichomes adaxially; anthers 1.5-2 mm long, ca. 1 mm wide, plumply ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age. Ovary globose, glabrous; style 4-5 mm long, straight, exserted beyond the anther cone, densely papillate in the lower third; stigma large-capitate and strongly bilobed, the surfaces minutely papillate, bright green in live plants. Fruit a globose to occasionally somewhat flattened-globose berry, 0.5-1 cm in diameter, orange-yellow or slightly greenish yellow when mature, the pericarp thin, matte to slightly shiny, translucent, glabrous; fruiting pedicels 0.6-1 cm long, ca. 1 mm in diameter at the base, ca. 1.5 mm in diameter at the apex, somewhat thickened and woody, deflexed and strongly bent at the base, not persistent; fruiting calyx not markedly accrescent, the tube appressed to the berry, the lobes to 3 mm long, spreading or reflexed in the distal half. Seeds 20-50 per berry, ca. 2 mm long, ca. 1.5 mm wide, teardrop shaped, not markedly flattened, reddish tan or pale tan, the surfaces minutely pitted, the testal cells sinuate in outline. Stone cells 5-6, with 2 larger, 1.2-1.5 mm in diameter and apically positioned, 3-4 smaller, 0.4-0.5 mm in diameter and throughout the berry flesh, all cream-coloured. Chromosome number: 2n = 24 ( Chiarini et al. 2017; voucher Särkinen et al. 4008).

Distribution

(Fig. 142 ). Solanum radicans occurs from Ecuador (Provs. Carchi, Chimborazo, Cotopaxi, El Oro, Esmeraldas, Imbabura, Pichincha, Tungurahua) and Peru (Depts. Arequipa, Apurímac, Ayacucho, Cajamarca, Cusco, Huancavelica, Huánuco, Ica, Junín, Lima, Moquegua, Piura, Tacna) to Bolivia (Depts. Cochabamba, La Paz) and central Chile (Regions I [ Tarapacá], III [Atacama], IV [Coquimbo], XV [Arica y Parinacota]). Most collections are from the western Andean slopes.

Ecology and habitat.

Solanum radicans is a plant of open places usually at high elevations but can occur to almost sea level in the southern part of its range, from (40-) 1,500 to 3,700 m elevation. It is generally a weedy species and is found in disturbed areas, often associated with human habitation.

Common names and uses.

Peru. Arequipa: uva de sapo ( Gonzáles J. 26); Cusco: cusmayllo (Valenzuela et al. 6189); Huánuco: bapichinga (Woytkowski 738); Lima: hierba mora (Espinoza 39); Moquegua: nucchu (Blanchard et al. s.n.), uva de sapo ( Núñez 5). No uses recorded.

Preliminary conservation status

( IUCN 2022). Least Concern [LC]. EOO = 2,210,753 km2 [LC]; AOO = 484 km2 [EN]. Solanum radicans is widely distributed and is often found in conjunction with people (in villages and along roadsides and streams). It has been collected around protected archaeological sites in Cusco (Peru).

Discussion.

Solanum radicans is a member of a small clade (Radicans clade of Särkinen et al. 2015b) also containing the Andean species S. corymbosum , S. palitans and S. tripartitum . Like them, it is a small herbaceous species that often occurs in disturbed areas. It differs from S. corymbosum in its 5-parted leaves (versus entire) and orange (versus bright red) berries. From S. palitans and S. tripartitum it differs in berry colour (orange versus red or yellow), consistently 5-parted leaves (versus 3-4-parted leaves) and usually violet flowers with a prominent globose green stigma. The buds of S. radicans are often dark purple, but at anthesis the corolla is usually white (Fig. 3D ).

No specimens or herbaria were cited in the protologue of W. ruderalis ( Rémy 1849), but the publication was largely based on the collections of Claudio Gay. We have selected the one of the two specimens of Gay 267 at Paris (P00370543) that has a label corresponding to the protologue text as the neotype of this name and combinations based upon it. The other specimen of Gay 297 at P (P00370544) has no annotations and is clearly a duplicate.

Figures

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 140. Solanum radicans A flowering habit B fruiting habit C detail of adaxial leaf surface D detail of abaxial leaf surface E flower bud F dissected flower G fruit (A, D-F Knapp et al. 10267 B Knapp et al. 10416). Illustration by R. Wise.

Figure 141. Solanum radicans A habit B flowering branch C flowers at full anthesis with flower buds D maturing fruits (A Saerkinen et al. 4065 B Knapp et al. 10417 C Gonzales et al. 2877 D Knapp et al. 10304). Photos by S. Knapp.

Figure 142. Distribution map of Solanum radicans.