Solanum incanum L.

Seed Collecting Guide. RBG Kew (2013-2016)

Morphology General Habit

erect herb to shurb, 0.4-1.5 m, prickly

Morphology Stem

young stems erect, robust, densely stellate-pubescent and prickly, bark of older stems orange-brown to grey

Morphology Leaves

lobed to almost entire, the blades 6-22 cm long, 4-15 cm wide, ca 1.5 times longer than wide, ovate, densely stellate-pubescent on both surfaces, with 0-5 prickles on both surfaces, petiole 1-9 cm long

Morphology Reproductive morphology Inflorescences

inflorescence 3-8 cm long, not branched, with 5-10 flowers, 1-3 flowers open at any one time, densely stellate­ pubescent, peduncle 1-4 mm long; pedicels 0.8-1.5 cm long in long-styled flowers, 0.5-0.9 cm long in short-styled flowers, 0-30 prickles on long-styled flowers, 0-5 prickles on short-styled flowers

Morphology Reproductive morphology Flowers

flower flowers 5-merous, heterostylous, lowermost flower long-styled and hermaphrodite, the distal flowers short­ styled and staminate

Morphology Reproductive morphology Flowers Corolla

corolla 2.4-3 cm in diameter in long-styled flowers, 1.5-2.3 cm in diameter in short-styled flowers, mauve, stellate, lobed for 1/3-1/2 of its length, broad-deltoid, spreading

Morphology Reproductive morphology Fruits

fruit a spherical berry, 1(-2) per infructescence, 2.5-3.5 cm in diameter, the pericarp smooth, dark green with pale green and cream markings when young, yellow at maturity; fruiting calyx not accrescent, covering ca 1/6 of the mature fruit, reflexed, with 5-60 prickles

Morphology Reproductive morphology Seeds

ca 100-200 per berry, 2.2-2.8 mm long, 1.8-2.3 mm wide, flattened-reniform, dull yellow to orange-brown.

Ecology

thickets, scrubland, and savanna. altitude0 – 1900m

Distribution

predominantly in Ethiopia, Somalia, Arabia, and India, with some populations in n Kenya, Sudan, and extending to Mali.

Conservation

least concerned

Phenology

Flower (january - december), fruit (january - december)

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit

Shrubs up to c. 1.5 m high, usually heavily armed with recurved prickles on the stem and straight prickles on the leaves, but rarely almost unarmed, densely white to pale greyish-white tomentose with floccose-stellate hairs

Morphology Leaves

Leaves alternate, of comparable size throughout the plant; petiole 0.7–5.5 cm long; blade somewhat leathery, ovate, 3–18(–23) x 1–10(–18) cm, base cordate or rounded, often unequal, margin entire to sinuate or lobed, apex bluntly acute, usually densely white tomentose to floccose on both sides, but particularly above

Morphology Reproductive morphology Inflorescences

Inflorescences lateral, sometimes ± leaf-opposed, 5–10-flowered, with one bisexual basal flower near the stem and functionally male flowers along densely tomentose up to 5 cm long rachis; peduncle 0–1.5 cm long; pedicels 1–3 cm long, the lowermost the longest, usually densely armed with small prickles

Morphology Reproductive morphology Flowers Calyx

Calyx 1–1.5 cm long, densely floccose, largest in the often very prickly basal flower, elongating to c. 2 cm in fruit; lobes lanceolate, c. 0.8 mm long

Morphology Reproductive morphology Flowers Corolla

Corolla stellate, pale to dark purple, c. 2.5 cm across; lobes broadly lanceolate to ovate, acute

Morphology Reproductive morphology Flowers Androecium Stamens Anthers

Anthers 3–4 mm long, subsessile

Morphology Reproductive morphology Flowers Gynoecium Style

Style in basal flower exceeding the anthers with 1–2 mm, reduced in upper flowers

Morphology Reproductive morphology Fruits

Fruit a tough or hard yellow berry, c. 2 cm in diam. Seeds pale brown.

Distribution

N1–3; C2; S1–3; widespread in tropical Africa and the Middle East, India.

Ecology

Altitude range 0–1550 m.

Samuels, J. Kew Bull (2012) 67: 401. https://doi.org/10.1007/s12225-012-9373-5

Morphology General Habit

Densely tomentose, armed perennial shrubs; up to 2 m high; with broadly ovate, sub-entire to repand leaves; up to 15 purple or violet flowers in each simple inflorescence, usually only one flower (more rarely up to 3) hermaphrodite; infructescence of up to 3 fruits, up to 3.5 cm diam.

Distribution

Across north-eastern Africa, extending southwards into Somalia and Kenya, westwards to Senegal, across the Middle East, and as far eastwards as northern Pakistan and northern India.

Solanaceae, Jennifer M Edmonds. Oliganthes, Melongena & Monodolichopus, Maria S. Vorontsova & Sandra Knapp. Flora of Tropical East Africa. 2012

Type

Type: ‘Africa’, Herb. J. Burser Vol. 9, no. 20 (UPS, neo., designated by Hepper & Jaeger 1985: 388)

Morphology General Habit

Herb or shrub, 0.4–1.5 m, erect, armed; young stems densely stellate-pubescent, trichomes multangulate, translucent, a mixture of sessile and stalked, stalks up to 1 mm, rays 6–20, 0.1–0.4 mm, midpoints ± same length as rays; prickles straight or curved, 3–9 mm long, 1.5–6 mm wide at base, round or flattened

Morphology Leaves

Leaf blades drying concolorous to weakly discolorous, yellowish, ovate, 6–22 × 4–15 cm, ± 1.5 times longer than wide, base rounded to cordate, often unequal and oblique, margin lobed to almost entire, the broadly rounded lobes (3–)4(–5) on each side, 0.5–2 cm long, apically rounded, extending up to 1/4 of the distance to the midvein; apex rounded to acute; densely stellate-pubescent abaxially, trichomes on abaxial surface porrect, sessile or stalked, stalks to 0.2 mm, rays 8–12, 0.15–0.5 mm, midpoints ± same length as rays or up to 0.6 mm, trichomes of adaxial surface smaller; primary veins ± 5 pairs; petiole 1–9 cm, 1/4–1/3 of the leaf length

Morphology Reproductive morphology Inflorescences

Inflorescences not branched, 3–8 cm long, with 5–10 flowers; peduncle 1–4 mm long; rachis 0.5–5 cm long; peduncle and rachis unarmed; pedicels 0.8–1.5 cm on long-styled flowers, 0.5–0.9 cm long on short-styled flowers, in fruit 1.3–1.8 cm long, with 0–15 prickles

Morphology Reproductive morphology Flowers

Flowers heterostylous, 5-merous, basal one long-styled flower

Morphology Reproductive morphology Flowers Calyx

Calyx 6–10 mm on long-styled flowers, 4.5–8 mm long on short-styled flowers, lobes long-deltate and sometimes foliaceous on long-styled flowers, broadly deltate on short-styled flowers, 2.5–5 mm on long-styled flowers, 1.5–3 mm long on short-styled flowers, acute to obtuse, with 15–60 prickles on long-styled flowers

Morphology Reproductive morphology Flowers Corolla

Corolla mauve, 2.4–3 cm in diameter on longstyled flowers, 1.5–2.3 cm in diameter on short-styled flowers, lobed for 1/3–1/2 of its length, lobes broadly deltate, 7–10 × 7–10 mm on long-styled flowers, 6–9 × 5–7 mm on short-styled flowers

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens equal; anthers 6–7.5 mm on long-styled flowers, 4.2–7 mm on short-styled flowers

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary stellate-pubescent in the upper 1/4; style 10–13 mm long on long-styled flowers

Morphology Reproductive morphology Fruits

Berries 1(–2) per infructescence, striped when young, yellow at maturity, spherical, 2.5–3.5 cm in diameter; fruiting calyx with 5–30 prickles

Morphology Reproductive morphology Seeds

Seeds 2.2–2.8 × 1.8–2.3 mm

Ecology

Thickets, bushland, wooded grassland; 500–800 m

Note

The name “ S. incanum” has been commonly and incorrectly applied to the widespread weedy species S. campylacanthum. Solanum incanum sensu stricto is distinguished by its lobed leaves, yellowish drying colour, adundant long-stalked indumentum, and does not occur any further south than K 1. Herbarium specimens of Solanum incanum bear a striking resemblance to the similarly yellowish and densely tomentose southern African S. lichtensteinii; the two species are not sympatric and geographical location data can greatly simplify the identification process. The ridged stems of S. lichtensteinii differentiate it from S. incanum. The majority of yellow-fruited weeds commonly encountered around East Africa are part of S. campylacanthum. Solanum incanum sensu stricto may be the closest African relative of the cultivated aubergine S. melongena (Weese & Bohs, Taxon 59: 49–56; 2010).

Distribution

Range: Egypt, Arabia, Oman, Israel, Jordan, Iran, Afghanistan, Pakistan, India Range: Senegal, Benin, Burkina Faso, Mali, Niger, Nigeria, Sudan, Eritrea, Ethiopia, Somalia Flora districts: K1

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/19241279/153935717

Conservation

LC - least concern

Flora Zambesiaca. Vol. 8, Part 4. Solanaceae. Gonçalves AE. 2005

Morphology General

Erect or spreading herb or shrub up to 3 m high, occasionally a small tree, usually armed but sometimes quite unarmed; hairs stellate, sessile to stalked, ± regular, some occasionally simple, mostly eglandular; prickles pale yellow to brownish, to 10 mm long, laterally ± flattened, recurved or straight, ± stout or slender, subulate from a broad base, hairy at the base to almost concealed by the tomentum

Morphology Stem

Stems one–many from an often deep taproot, woody rootstocks or rhizomatous structures.

Morphology Branches

Branches with white to greyish, yellowish, brown or purplish tomentum, sometimes scurfy, or occasionally floccose, to sparsely hairy, becoming subglabrous with age, generally with scattered prickles

Morphology Leaves

Leaves usually solitary; petiole 0.2–8.5 cm long; lamina felty or relatively thin, 1. 5–30.5 × 0.5–17 cm, sub-orbicular or broadly ovate to narrowly elliptic or lanceolate, base sub-cordate, truncate or rounded to tapering into the petiole, and ± unequal-sided, apex obtuse or acute, sometimes acuminate or mucronate, entire to pinnately lobed, the lobes broad, ± triangular, obtuse or rounded, the sinuses rounded between the lobes, usually tomentose, the upper surface with ± equal-rayed or occasionally forked hairs, becoming scabrous or subglabrous, paler and more densely hairy beneath, sometimes mealy, or occasionally velvety, both surfaces often with a few short prickles mostly along the midrib and sometimes also on the nerves

Morphology Reproductive morphology Inflorescences

Cymes lateral, often leaf-remote but also leaf-opposed or axillary, simple or forked, sub-umbelliform, racemiform or paniculiform, 2–15(26)-flowered, usually only lowest flower(s) larger and fertile, more rarely all flowers fertile, rarely flowers solitary; peduncle 0–4(5) cm long, often with short, fine prickles

Morphology Reproductive morphology Flowers

Flowers fragrant, nodding or pendulous.

Morphology Reproductive morphology Flowers Pedicel

Pedicels 0.2–3 cm long, slender or ± thickened especially upwards in fertile flowers, densely prickly to quite unarmed in male flowers, in fruit elongated to 4 cm

Morphology Reproductive morphology Flowers Calyx

Calyx tomentose to hairy outside with white, ashy, pale yellowish to brown, golden or violet hairs, often ± prickly in fertile flowers or quite unarmed, 3–22 mm long, 4–21 mm across, broadly campanulate or cupular, (4)5–7(9)-lobed; lobes ± unequal, 1–13 × 1–8 mm, ovate or triangular to lanceolate-subulate, obtuse to long-acuminate, spreading, in fruit ± enlarged to 25 mm, sometimes splitting irregularly

Morphology Reproductive morphology Flowers Corolla

Corolla bluish to pink or purplish to violaceous, occasionally darker, purple or white at the veins, rarely white or almost so, (0.8)1–3 cm long, campanulate to rotate, or broadly stelliform; limb (1)1. 5–4(4.5) cm across; lobes (2.5)5–16 × (2)3–15 mm, ovate or broadly triangular to lanceolate, obtuse to shortly acuminate or apiculate, tomentose to hairy outside on the mid-petaline areas, and similarly along the midveins or glabrous inside, ± spreading or reflexed

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens (4)5–7(8); filaments 0.5–2.5 mm long; anthers (4)5–9 mm long, stout, oblong to linear-lanceolate in outline, straight or slightly curved, obtuse, slightly emarginate at both ends, free or in a narrow cone surrounding the style

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary 2.5–4 mm long, ± globose or ovoid, densely hairy on top, occasionally clothed with a rusty tomentum, 2(4)-locular.

Morphology Reproductive morphology Flowers Gynoecium Style

Style 7–17 mm long, in male flowers only 2–5 mm long, straight or slightly incurved distally, tomentose or covered with simple hairs except for the apex, sometimes hairy only at the base, very rarely glabrous, exserted or included

Morphology Reproductive morphology Fruits

Fruit dark to pale green, often basally green and distally paler or white, sometimes mottled, veined or striped cream or white to dark green, on ripening yellowish to orangish or brownish, (1)1. 5–5.5 cm in diameter or 2.5–3.5 × 2–3 cm, globose or depressed-globose, occasionally ovoid-ellipsoid, bitter and said to be poisonous

Morphology Reproductive morphology Seeds

Seeds pale yellow to brownish, numerous, 2.5–3.5 × 2–3 mm, obliquely lenticular or sub-reniform, sub-tuberculate

Ecology

Generally found as a weed of cultivated ground, around old habitations and in overgrazed grassland, but extending into forest, mostly at the edges, riverine vegetation, various types of woodland and savanna-woodland, including miombo, mopane and Acacia woodland, thickets, bushland and littoral scrub, grasslands, floodplains, stream-banks, termitaria; from sea level to 2438 m.

Note

— representing distinct species. From these studies, including chloroplast DNA analyses, they conclude that these groups can be recognized as separate species within the aggregate. Most of the material from the Flora Zambesiaca area falls within group B, with a few specimens from northern Malawi more like Group A, which is predominant further north in E and NE Africa. Group C, S. incanum in a strict sense, does not occur in the Flora Zambesiaca area, but the rather similar group D, S. lichtensteinii, is quite common and also occurs widely in southern Africa. A more hairy element is considered now by Lester (pers. comm.) as a further separate species, S. aureitomentosum Bitter, but it does, however, intergrade with S. lichtensteinii. — group A (possible name: S. campylacanthum Hochst. ex A. Rich.; group B (possible name: S. delagoense Dunal (S. panduriforme in the earlier papers)); group C (possible name: S. incanum L. sensu stricto); and group D (possible name: S. lichtensteinii Willd., among others) Group A (S. campylacanthum Hochst. ex A. Rich.): similar to the more common Group B, but leaves distinctly broader. Common name: “Thorn Apple”. Lester & Hasan, loc. cit. (1990), in Hawkes, Lester, Nee & Estrada, eds., Solanaceae III: 369–387 (1991) and Lester & Daunay in Knüpffer & Ochsmann, (eds.), Rudolf Mansfeld and Plant Generic Resources, Schriften. Genet. Ressourcen 22: 137–152 (2003), consider the distinction between S. melongena and S. incanum. Within S. incanum sens. ampl., they recognize four taxa S. incanum has been treated either as a true species or as a variety of S. melongena L., appearing to comprise several geographically or ecologically localized infraspecific taxa (subspecies or varieties), considered distinct in the form, length-width relation and indumentum of the leaves. Deb, loc. cit. (1989) considers S. melongena (the “eggplant”), originally from Indo-Burma Region (probably first domesticated in India), a cultivated form of the wild S. incanum and often a weed developed in the course of cultivation, suggesting that they are conspecific. The phenotypic variations observed in both taxa, mainly in the pubescence, density of prickles, size, form and location of the leaves, and in the size, form, colour and edibility of the fruits (these ones however larger, mostly pulpy and edible in S. melongena), and the possible hybridization, eliminate their specific distinction.

Distribution

A common and polymorphic species of as yet undefined limits, from unknown origin, widespread throughout the Old World tropics, nowadays widely distributed in equatorial, tropical and subtropical S and N Africa, extending to SW Asia. BOT N, BOT SW, BOT SE, ZAM B, ZAM N, ZAM W, ZAM C, ZAM E, ZAM S, ZIM N, ZIM W, ZIM C, ZIM E, ZIM S, MAL N, MAL C, MAL S, MOZ N, MOZ Z, MOZ T, MOZ MS, MOZ GI, MOZ M, MAL N Zambia Mozambique Malawi Zimbabwe Botswana. Malawi