Citation:
Sp. Pl. 186. 1753.
Type:
Peru. sin. loc., Jussieu s.n. (lectotype, LINN 248-17 [BH neg. 6804], designated by Knapp & Jarvis 1990).
Written by:
Peralta, I.E., S. Knapp & D.M. Spooner
Habit:
Spreading to erect perennial herbs to small shrubs, woody at the base, to 0.5 m tall, to 1 m in diameter. Stems 3-5 mm in diameter at base, pale grayish green, densely and uniformly velvety pubescent with white, simple, uniseriate eglandular trichomes less than 0.5 mm long with a bent tip, and scattered glandular uniseriate trichomes with 1-celled, 4-celled or 8-celled heads amongst and shorter than the eglandular trichomes, all trichomes with unicellular bases, the young stems more densely pubescent and if present, more glandular.
Sympodial structure:
Sympodial units 2-foliate; internodes 1.5-5 (10) cm long.
Leaves:
Leaves interrupted imparipinnate, 4-10 (-19) cm long, 1.6-7 (-10) cm wide, grayish green above and below, densely velvety pubescent like the stems with simple, uniseriate trichomes to 0.5 mm long, mixed with sparse scattered shorter glandular trichomes with 4-celled heads; primary leaflets 2-4 pairs, elliptic to almost orbicular in some populations (mostly in the southern part of the range), the base truncate, markedly oblique and decurrent basiscopically, the margins entire to crenate to more or less deeply lobed 1/4-1/3 of the way to the leaflet rachis, the apex bluntly acute to rounded; terminal leaflet usually markedly larger than the laterals, 1.5-3.5 (6) cm long, 0.6-1.5 (4) cm wide, the petiolule 0.2-0.8 cm long; lateral leaflets 0.8-3 cm long, 0.5-1.5 cm wide, sessile and the base decurrent or the petiolule to 0.5 cm long; secondary leaflets very occasionally present on the larger lower lateral leaflets, 0.1-0.3 cm long, 0.1-0.3 cm wide, sessile, often appearing as mere lobes at the base of the lateral leaflets; tertiary leaflets absent; interjected leaflets (0-) 2-9, 0.1-0.7 cm long, 0.15-0.9 cm wide, sessile or in extremely large leaves with a petiolule of 0.1-0.5 cm long; petiole 1-3 cm long; pseudostipules present and developed in all nodes, 0.2-1 cm long, 0.3-1.1 cm wide, the margins crenate or entire.
Inflorescences:
Inflorescences (4-) 8-16 cm long, usually once-branched and bifurcate, occasionally more than once-branched, with 8-20 flowers, all nodes bracteate, the bracts 0.1-1 (-1.5) cm long, 0.2-1.5 (-2) cm wide, cordate and surrounding the pedicels, the largest bract at the first inflorescence branch, peduncle (1.5-) 4-10 cm long, densely white velvety pubescent like the stems and leaves. Pedicels 1-1.5 cm long, articulated in the proximal half or at the middle. Buds 0.8-1.2 cm long, 0.3-0.4 cm wide, elongate conical, strongly curved, with the corolla more than halfway exserted from the calyx just before anthesis.
Flowers:
Flowers with the calyx tube minute, the calyx divided essentially to the base, the lobes 0.5-0.7 cm long, 0.15-0.2 cm wide, lanceolate, densely white velvety pubescent like the rest of the inflorescence on both surfaces; corolla 1.7-2.3 cm in diameter, rotate to slightly stellate, bright yellow with the midveins occasionally darker, the tube 0.6-0.8 cm long, the lobes 0.6-0.8 cm long, 0.8-0.9 cm wide, densely white pubescent on the tips and margins, reflexed at anthesis; staminal column 0.8-1.3 cm long, strongly curved, the filaments completely united into a tube ca. 0.5 mm long, the anthers 0.5-0.7 cm long, the upper two usually longer and curved, the sterile apical appendage 0.3-0.4 cm long, often greenish; ovary conical, minutely puberulent at the apex or over entire surface; style 1-1.5 cm long, ca. 0.5 mm in diameter, curved, densely white pubescent in the basal 2/3, exserted 0.5-1 mm from the staminal column; stigma capitate to slightly clavate.
Fruits:
Fruit 1-1.5 cm in diameter, globose, green to greenish white of ten flushed with purple, with a dark green or purple stripe from the apex to base at fruit maturity, 2-locular, pubescent to densely pubescent with soft, weak-walled simple uniseriate trichomes to 0.5 mm long, the surface densely papillate; fruiting pedicels 1.5-2 cm long, often straight or slightly bent at the articulation; calyx lobes in fruit 1-1.4 cm long, 0.2-0.25 cm wide, narrowing just distal to the sinus, loosely investing the berry or spreading.
Seeds:
Seeds 1.8-3.0 mm long, 1.0-1.4 mm wide, 0.5-0.7 mm thick, obovate, dark brown, pubescent with hair-like outgrowths of the lateral testa cell walls, these adpressed to the coat giving a silky appearance to the surface or sometimes shaggy, narrowly winged (0.2 mm) at the apex and acute at the base.
Distribution:
In lomas formations and occasionally in coastal deserts from central Peru to northern Chile, sea level to 600 m; occasionally occurring as a weed at field edges in coastal river valleys.
Phenology:
Solanum peruvianum flowers and fruits throughout the year, but with an extended peak from September through December, during the coastal foggy period.
Phylogeny:
Solanum peruvianum is a member of the Potato clade (sensu Weese & Bohs, 2007); within the tomatoes and wild relatives it is a member of the “Eriopersicon group” and is a member of section Lycopersicon.
References:
Linnaeus, C. 1753. Species Plantarum, 1st ed.
Stockholm: L. Salvius.
Stafleu, F.A. 1971. Linnaeus and the Linnaeans: the spreading of their ideas in systematic botany, 1735-1789.
Utrecht: A. Oosthoek, IAPT
Knapp, S. & C.E. Jarvis 1990. The typification of the names of New World Solanum species described by Linnaeus.
J. Linn. Soc., Bot. 104: 325-367.
Jørgensen, P.M. 1999. History of collecting/Historia de las collections botánicas.
Pp. 25-70 in Catalogue of the vascular plants of Ecuador/Catálogo de las plantas vasculares del Ecuador, ed. P. M. Jørgensen, and S. León Yánez.
Taxonomic name:
Solanum peruvianum is a member of the clade containing S. corneliomulleri, S. chilense and S. huaylasense (+ in some analyses S. habrochaites). It is distinguished from its close relatives by the character combination of uniform, dense, velvety pubescence with only scattered short glandular hairs (in contrast to the longer glandular hairs of S. corneliomulleri), usually strongly bracteate inflorescence and curved anther tube. The peduncle in S. peruvianum usually is equal or shorter than the length of the inflorescence branches, and is consistently shorter than that of S. chilense and S. huaylasense. There is considerable variation in leaf morphology in populations of S. peruvianum along the Peruvian coast. More northerly populations around Lima and the Department of Ancash have leaflets that are crenate to deeply lobed to 1/4 of the way to the rachis and inflorescences that are sometimes almost ebracteate. The other populations of S. peruvianum from the southern part of the species range (e.g. Lomas de Atico, Department of Arequipa) have nearly entire leaflets and very large inflorescence bracts. Solanum peruvianum is a low elevation coastal species, characteristic of the lomas vegetation (see Ecology and Natural History above). The table lists all the TGRC accessions (LA numbers) previously included in Rick’s broad definition of S. peruvianum with their current identification.
Solanum peruvianum was one of the first wild tomatoes to be cultivated in European botanical gardens. Original introductions appear to have come from at least two different parts of the species range. The type specimen of S. peruvianum in the Linnaean herbarium (LINN, see http://www.linnean.org) and plants grown by Philip Miller in the Chelsea Physic Garden in the early 18th century match plants from the area around Lima, Peru, while many continental botanical gardens such as Berlin, Vienna and Hamburg (e.g. Sprengel’s Solanum commutatum) had plants whose morphology is more similar to that of plants collected in more southern Peruvian populations. We have selected the neotype for Sprengel’s name from amongst these specimens (Fig. 40). The neotype we have chosen for Sprengel’s name Solanum commutatum is annotated with a small tag in what is an extremely close match to Sprengel’s handwriting. Heinrich Gustav Reichenbach (Reichenbach filius), the great German orchidologist, had specimens from Sprengel’s herbarium in his own collection which was bequeathed to the Naturhistorisches Museum in Vienna (W). The sheet we have chosen as the neotype for S. commutatum matches the description of Solanum commutatum and is likely to have been from the same material grown in botanic gardens at the time Sprengel named S. commutatum.
It is probable that Linnaeus (1753) received the seeds from which he cultivated his specimen of S. peruvianum in Uppsala from Bernard de Jussieu (Knapp & Jarvis 1990); he indicated in the introduction to Species Plantarum that he had received seeds from “B. Jussieu” and he cited “Jussieu” in the protologue of S. peruvianum. Bernard de Jussieu’s younger brother Joseph was a member of the expedition of Charles-Marie de la Condamine (Stafleu 1971) to equatorial South America from 1735-1743, where he collected plants in Ecuador and afterwards in Peru and Chile (Jørgensen 1999). He certainly sent seeds back to his brother from the region, these may have been the source of the plant cultivated by Linnaeus in Uppsala.