Solanum interandinum Bitter, Repert. Spec. Nov. Regni Veg. 11: 217. 1912.

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

26. Solanum interandinum Bitter, Repert. Spec. Nov. Regni Veg. 11: 217. 1912.

Figs 80 , 81

Solanum onagrifolium Bitter, Repert. Spec. Nov. Regni Veg. 11: 216. 1912. Type. Ecuador. "crescit in tota altiplan. Frequens", A. Sodiro, A. 114/12 (holotype B, destroyed [F neg. 2677]; lectotype, designated here: QPLS).

Solanum egranulatum Bitter, Repert. Spec. Nov. Regni Veg. 11: 217. 1912. Type. Ecuador. "In altiplanitie interandina", A. Sodiro 114/12 pro parte (holotype: B, destroyed [F neg. 2660, of sheet annotated as Solanum egranulosum by Bitter]; lectotype, designated here: QPLS).

Solanum densepilosulum Bitter, Repert. Spec. Nov. Regni Veg. 11: 218. 1912. Type. Ecuador. Sin. loc. "in tota altiplanitie passim una cum S. onagrifolium , S. interandinum , S. egranulatum sub nom. " S. pterocaulon Dunal" a cl. Sodiro lectum herb. Berol.", A. Sodiro (no specific collection cited).

Solanum soriae Heiser, Ci. & Naturaleza [Quito] 6: 57. 1963. Type. Ecuador. Pichincha: Lloa, in fence row by stream, C.B. Heiser 5093 (holotype: IND [IND1000062]; isotype: IND [IND1000061]).

Solanum pentlandii Dunal subsp. interandinum (Bitter) Edmonds, Kew Bull. 27: 110. 1972. Type. Based on Solanum interandinum Bitter.

Solanum melanostictocarpum Gilli, Repert. Spec. Nov. Regni Veg. 94: 321. 1983. Type. Ecuador. Chimborazo: Rain bei Cuatras Esquinas NO von Guaranda, A. Gilli 97 (holotype: W [acc. # 1981-0011277]).

Solanum zahlbruckneri Bitter, Repert. Spec. Nov. Regni Veg. 11: 203. 1912. Type. Peru. Cajamarca. Cutervo, C. de Jelski 46 (holotype: W [acc. # 1891-0004329]; isotypes: F [v0043302F, acc. # 871534, fragment of holotype], MO [MO-3008928, acc. # 1691555], S [acc. # 04-2998]).

Type.

Ecuador. "In tota altiplanitie passim, communissima in altiplanitie interandina", A. Sodiro 114/12 pro parte (holotype: B, destroyed; lectotype, designated here: QPLS) .

Description.

Small shrubs or occasionally woody herbs to 1 m high, the branches erect, always woody at base. Stems terete or angled, if angled the wings to 1 mm wide and with spinescent processes, sparsely pubescent with white eglandular simple uniseriate 2-7-celled trichomes 0.5-0.75 mm long, these usually antrorse; new growth densely to moderately pubescent with the same simple uniseriate trichomes as those of the stems; bark of older stems brown, glabrescent. Sympodial units difoliate to plurifoliate, the leaves usually not geminate, but sometimes appearing paired. Leaves simple, occasionally shallowly lobed, the blades 1.8-7.5(12) cm long, 0.8-4(5.5) cm wide, narrowly elliptic to elliptic, sometimes slightly ovate, widest in the lower third, membranous, discolorous; adaxial surfaces sparsely to moderately pubescent with usually transparent antrorse eglandular simple uniseriate trichomes 0.5-1 mm long; abaxial surfaces densely pubescent with tangled white eglandular simple uniseriate trichomes 0.5-1 mm long; principal veins 5-7 pairs, obscured by pubescence below in dry specimens; base attenuate onto the petiole; margins entire; apex acute; petioles 0.3-2 cm long, narrowly winged from the leaf bases. Inflorescences internodal or opposite the leaves, forked or several times branched, 1.5-5(7) cm long, with 10-20 flowers densely or loosely clustered at the branch tips, pubescent with white eglandular simple uniseriate 2-7-celled trichomes 0.5-0.75 mm long, these usually antrorse; peduncle 1-5 cm long; pedicels 0.4-0.6 cm long, ca. 0.5 mm in diameter at the base, ca. 0.75 mm in diameter at the apex, slightly tapering, spreading at anthesis, pubescent with white eglandular simple uniseriate trichomes like the rest of the inflorescence, articulated at the base; pedicel scars 0-1.5 mm apart in the distal part of the inflorescence branches. Buds ellipsoid, the corolla strongly exserted from the calyx before anthesis, the style often exserted in bud, the buds appearing striped in live plants. Flowers 5-merous, cosexual (hermaphroditic). Calyx tube 0.5-1.2 mm long, conical from the tapered pedicel, the lobes ca. 1 mm long, 0.75-1 mm wide, deltate to broadly triangular with acute apices, pubescent with antrorse white eglandular simple uniseriate 2-7-celled trichomes 0.5-0.75 mm long. Corolla 0.8-1.4(1.8) cm in diameter, pale violet or white and violet striped or violet abaxially, stellate, lobed 2/3 to 1/2 way to the base, the lobes 4-6 mm long, 3-4 mm wide, deltate, spreading or reflexed, adaxially glabrous, abaxially evenly papillate-puberulent with simple trichomes to 0.2 mm long, these denser at the tips and margins. Stamens equal; filament tube minute; free portion of the filaments 0.5-1 mm long, densely pubescent with tangled transparent simple uniseriate trichomes adaxially; anthers 2.5-3 mm long, 1-1.4 mm wide, ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age. Ovary conical, glabrous; style 5.5-7 mm long, straight, often curved in bud, exserted beyond the anther cone, densely puberulent in the lower half or 2/3; stigma small capitate, the surfaces minutely papillose. Fruit a globose berry, 0.6-0.8 cm in diameter, whitish green when immature, ripening to green or green with irregular black-purple blotches, the pericarp thin, matte, opaque, glabrous; fruiting pedicels 0.9-1 cm long, ca. 1 mm in diameter at the base, ca. 1.2 mm in diameter at the apex, woody, strongly deflexed, not persistent, but peduncle and inflorescence branches persistent on older stems; fruiting calyx not markedly enlarged, the lobes 2-2.5 mm long, ca. 1.8 mm wide, strongly appressed to the berry. Seeds 30-60 per berry, ca. 1.5 mm long, 1.1-2 mm wide, flattened and teardrop shaped to reniform, pale reddish brown or cream, the surfaces minutely pitted, the testal cells sinuate in outline. Stone cells 6-10 per berry, ca. 0.5 mm in diameter, cream-coloured, distributed throughout the berry. Chromosome number: n = 12 ( Heiser 1963, vouchers Heiser 4920, 4922, 4973, 5085, 5093, 6037, 6061, 1697, as S. soriae ); n = 24 ( Heiser 1963, vouchers Heiser 4962a, 4978, 5084, 6017, 6020, 6021, 6051, 6068); n = 48 (number written on herbarium vouchers Heiser 4993, 5081, 6081).

Distribution

(Fig. 82 ). Solanum interandinum is a common species and is widely distributed in the Andes in Colombia (Antioquia, Boyacá, Cauca, Cundinamarca, Huila, La Guajira, Magdalena, Nariño, Norte de Santander, Putumayo, Santander, Valle de Cauca), Venezuela (States of Mérida, Táchira), Ecuador (Azuay, Bolívar, Cañar, Carchi, Chimborazo, Cotopaxi, Imbabura, Loja, Los Rios, Manabí, Napo, Pastaza, Pichincha, Tungurahua) to central Peru (Depts. Amazonas, Ancash, Arequipa, Apurímac, Ayacucho. Cajamarca, Cusco, Huancavelica, Huánuco, Junín, La Libertad, Lima, Piura, Puno, San Martín), with a southerly collection from Bolivia (Dept. La Paz, Plowman & Davis 5135).

Ecology and habitat.

Solanum interandinum grows in open areas in high elevation cloud forests and forest margins ('ceja de selva’); most collections have been made between 1,000 and 4,000 m elevation, but a few collections from the western slopes of the Andes in both Ecuador and Peru have been made at lower elevations (50 to 600 m).

Common names and uses.

Colombia. Caldas: yerba mora (Grisales 9); Putumayo: yerbamora (Criollo 16); Ecuador. Azuay: hierba mora ( Cerón 16328), moradilla ( Cerón 115617), mortiño ( Cerón 15277, 15323, 16051, 16328, 16351); Bolivar: hierba mora ( Argüello 118, Falconi & Argüello 79); Cañar: hierba mora ( Cerón 14476, 14957, 16076, 16459, 17636), mortiña (Camp & Prieto E-2467, Cerón 14857); Carchi: hierba mora ( Cerón 6974); Chimborazo: hierba (yerba) mora (Caranqui 1244, Cerón 14651, 14716, 15198, 15377, 16478, 17458, Cerón & Gallo 19626); Cotopaxi: yerba (hierba) mora (Barclay & Juajibioy 8038, Cerón 7087, Cerón et al. 11617); Imbabura: hierba mora (Bailey 73, Cerón & Montesdeoca 12527); Manabí: yerba mora, pili muyo ( Prácticas de Recolección s.n.); Napo: huami hierba mora, yerba mora embra (Baez et al. 31); Pichincha: hierba mora (Ugent & Ugent 5579, Cerón 6841, Chiriboga Q. 27, Mantilla 41, Mena et al. 466, Paredes 145, Prácticas de Recolección s.n., 32, Putcher 55, 128, 251, Vargas N. s.n.), pili muyo ( Prácticas de Recolección 32); Tungurahua: hierba (yerba) mora (Delgado et al. 177, Lligado 51, Paredes s.n.), jachafili (Quichua, Lligado 51); Peru. Puno: muña mayo (Hoogte 3836). Venezuela. Mérida: yerba mora (Gehriger 15). No uses recorded.

Preliminary conservation status

( IUCN 2022). Least Concern [LC]. EOO = 13,454,357 km2 [LC]; AOO = 1,148 km2 [EN]. Solanum interandinum is a common, widely distributed species that occupies disturbed and open habitats. It is found in several protected areas within its range (e.g., common in Parque Nacional Huascarán, Peru).

Discussion.

Solanum interandinum is one of the commonest species of morelloids in the northern Andes and is called hierba mora (black nightshade) throughout its range. It is highly variable, as are most widespread morelloid species (see discussion of synonymy below); plants with the flowers clustered at the tips of the inflorescence branches have been called S. interandinum whereas those with the flowers more spaced along the inflorescence axes have been called S. zahlbruckneri .

Solanum interandinum is a small shrub where the old, forked inflorescences remain on the plant long after the fruits have fallen (along with their pedicels). The leaf margins are usually entire and only rarely with some shallow lobing near the base and leaf size is highly variable within and between individual plants. It is morphologically similar to S. nigrescens in northern Colombia and Venezuela, S. cochabambense in Peru and S. gonocladum in Peru and Bolivia. Solanum nigrescens is a more herbaceous plant, with an unbranched (very occasionally forked) inflorescence that is not woody and persistent after fruit fall. Anthers of S. interandinum are longer (2.5-3 mm long on filaments 0.5-1 mm long versus 2-2.8 mm long on filaments 0.5-2 mm long) relative to the filaments than those of S. nigrescens , and the calyx lobes are more than 1 mm long and long-triangular rather than less than 1 mm long and deltate to broadly deltate in S. nigrescens . Solanum cochabambense is a much larger plant, with more branched (rather than always forked) inflorescences and larger flowers (2-3 cm in diameter with anthers 3.5-4.5 mm long versus 1-1.2 cm in diameter with anthers 2-3 mm long in S. interandinum ). In central Peru it can be very difficult to tell these two species apart with single herbarium specimens, and it is possible they hybridise. In northern Bolivia and southern Peru S. interandinum is somewhat confusable with S. gonocladum , but that species has larger flowers (1.3-2 cm in diameter with anthers 4-4.5 mm long versus 1-1.2 cm in diameter with anthers 2-3 mm long in S. interandinum ) and spathulate (rather than apically pointed) calyx lobes. Both these species have calyx lobes that dry dark in herbarium specimens.

Bitter (1912b) appears to have used different duplicates of Sodiro 114/12 in Berlin to describe S. interandinum , S. egranulatum , S. onagrifolium and (probably) S. densepilosum . The only Macbride photographs of any of these are of sheets annotated by Bitter as S. onagrifolium (F neg. 2677) and S. egranulatum (F. neg. 2660). These clearly correspond to the same species, if not the same gathering. Bitter often used duplicates of the same gathering as the basis for both infraspecific and specific epithets based on minor differences in leaf shape (e.g., S. ruizii S.Knapp, see Knapp 2013; S. gonocladum in this monograph); S. interandinum , however, is the most extreme case we have ever encountered. We have only found a single sheet of Sodiro 114/12 in QPLS, which we have designated as the lectotype of all these names (see above), except S. densepilosum which was characterised as "in tota alta planitie passim una cum S. onagrifolium , S. internadinum, S. egranulatum sub nom. " S. pterocaulon Dun." a cl. Sodiro lectum herb. Berol" ( Bitter 1912b). Solanum densepilosum is distinguished as a species with intermediate sized anthers, and with enlarging fruiting calyces. Based on description alone, it is hard to assign the name to any existing species with certainty, but it fits within the circumscription of S. interandinum here. Because the original description lacks any specific locality, there is little possibility of re-collecting type material. We place it in synonymy here, but without designating a neotype. Of all of these simultaneously published names, S. interandinum is the only one that has been previously used ( Edmonds 1972; Short and Knapp 1999), so we reduce the others to synonymy.

Figures

Figure 80. Solanum interandinum A habit B flowering habit with smaller leaves C detail of adaxial leaf surface D detail of abaxial leaf surface E eglandular multicellular trichome on stem and leaves F flower bud G dissected flower H gynoecium I fruit J seed K seed, cross section L embryo M stone cell (A, C, D, F, G, I Fosberg 20565 B Hitchcock 21006 E, H, J-M Cabrera 13875). Illustration by R. Wise and M. T. Cabrera.

Figure 81. Solanum interandinum A habit B inflorescence with bud C flowers at full anthesis D maturing fruits (A Saerkinen et al. 4693 B-D Knapp et al. 10259). Photos by S. Knapp and T. Saerkinen.

Figure 82. Distribution map of Solanum interandinum.