Solanaceae

Herbs, annual or perennial, vines, shrubs, or trees, sometimes rhizomatous or tuberous, usually hermaphroditic, sometimes gynodioecious or dioecious in Lycium [andromonoecious or dioecious in some Solanum]. Stems erect or decumbent to prostrate, sympodially branched, glabrous or pubescent, hairs simple, dendritic, or stellate, stalked-vescicular in Quincula, sometimes peltate scales in Solanum, glandular or eglandular, glands sessile or stalked and sometimes multicellular, sometimes prickly or spiny. Leaves alternate and spiral or unequally paired, simple or pinnately compound [trifoliolate], estipulate, petiolate or sessile; blade margins entire, dentate, lobed, or divided. Inflorescences terminal, axillary, extra-axillary, in forks of dichotomous branches in some Datura and Solanum, racemose, paniculate, umbellate, or glomerulate cymes, in fascicles of 2–6, or solitary flowers. Flowers bisexual or rarely unisexual, radially symmetric or, less frequently, bilateral; perianth and androecium hypogynous; sepals (4 or)5, connate for almost full length to only at base, tubular, campanulate, obconic, or cyathiform [urceolate], with 3–10 equal or unequal lobes, lobules, or teeth, 5–10 veins extending into appendages that protrude below a truncate rim in Lycianthes, bases of lobes sagittate to cordate in Nicandra; calyx usually persistent in fruit and often accrescent, circumscissile and leaving a basal remnant that is slightly enlarged in some species of Datura, sometimes spreading, reflexed, or expanded to partially or completely enclose fruit, sometimes becoming membranous, sometimes inflated and bladderlike; petals (4 or)5, connate for almost full length to only at base, stellate, campanulate, campanulate-rotate, rotate, funnelform, salverform, or urceolate [crateriform, cylindric], margins nearly entire or shallowly to deeply 4–10-lobed, lobes sometimes widely flaring or reflexed, corona present between tube and limb in Nectouxia; stamens (2 or 4 plus staminodes or)5, variously adnate to corolla from near base nearly to rim, with appendage at point of fusion in Cestrum, equal or unequal in length, anthers sometimes connivent, basi-, dorsi-, or ventrifixed, with unequal thecae in Bouchetia, Browallia, and Hunzikeria, connective sometimes thickened, with 2 dorsal wings in Nectouxia, dehiscence longitudinal or poricidal; pistil 1, 2–5-carpellate; ovary superior, nectary disc sometimes present at base, [1 or]2–5[or 10]-locular, [1 or]2–many ovules per locule, placentation axile; style 1, stigma rounded-truncate, capitate, or 2–5-lobed. Fruits usually berries or 2–4-valved capsules, dehiscence septicidal, circumscissile, or irregular [septifragal, septicidal-loculicidal], sometimes drupaceous in Lycium [schizocarp of nutlets in Nolana]. Seeds 1–many, whitish to straw-colored to dark brown or black, often flattened and discoidal or reniform, sometimes globose, ovoid, prismatic, or angulate, with hyaline margin in Oryctes, with white caruncle in some species of Datura, intermixed with sclerotic granules in Calliphysalis and some Solanum; embryo straight or curved, endosperm usually abundant.

Distribution

nearly worldwide.

Discussion

Genera ca. 97, species ca. 2500 (27 genera, 151 species, including 2 hybrids, in the flora).

Solanaceae occur on all continents except Antarctica, but their greatest diversity is in the Neotropics. Their closest relative is the Convolvulaceae, from which they can be distinguished by growth form (when herbaceous vines, not with twining stems), the usually 2-locular ovary with numerous ovules, and the absence of laticifers with milky sap. Members of the Solanaceae exhibit a sympodial growth pattern, resulting in unusual placement of leaves, branches, and flowers (A. Child 1979). The foliage of some Solanaceae is fetid or pungent (reminiscent of rotting potatoes or with a sharp, tomato-like smell). The vegetative portions of most members of the family are poisonous due to the presence of tropane and steroidal alkaloids.

Despite the toxicity of its foliage, many Solanaceae species are of worldwide economic importance, such as tomato (Solanum lycopersicum), eggplant (S. melongena), potato (S. tuberosum), chili and bell peppers (Capsicum spp.), tobacco (Nicotiana tabacum), and Petunia. The family also includes many species of small-scale crop, medicinal, or horticultural importance. The most well known of these in the flora area are tomatillo (Physalis philadelphica), belladonna (Atropa belladonna), goji berry (Lycium barbarum and L. chinense), Chinese lantern plant (Alkekengi officinarum), jimsonweed (Datura spp.), jessamine (Cestrum spp.), and Calibrachoa.

The fruit in the Solanaceae is typically a berry or capsule (with circumscissile dehiscence in Hyoscyamus), but may be hardened and drupaceous in some Lycium. The berry-fruited taxa may have a thick, juicy pericarp, or one that is dry and thin, ultimately shattering into irregular pieces. Many genera have an accrescent calyx. The most enlarged of these may become rigid and spinescent (Hyoscyamus), inflated and almost closed around the berry (Alkekengi, Calliphysalis, Physalis, Quincula), loose and enveloping all (Nicandra) or at least the basal half of the berry (Chamaesaracha), or reflexed or flaring (Jaltomata). The brightly colored, juicy berries of many species are animal dispersed. The inflated, bladderlike calyces in several genera also aid in dispersal (short distance by water or ground level by wind).

The showy flowers of Solanaceae are pollinated by bees, flies, butterflies, moths, or humming­birds foraging for nectar and/or pollen. Solanum does not produce nectar, and pollen is gath­ered by vibration (buzz pollination) or manipulation of the anthers. Flowers of Cestrum, Datura, and some Nicotiana emit a strong, sweet fragrance in the evening and are moth-pollinated.

Some Solanaceae grown as ornamentals have escaped and persisted for short periods but have not become established in the flora. Nierembergia hippomanica Miers var. coerulea R. Millan has been collected from disturbed sites in Texas (1958, 1962, 1998), and N. scoparia Sendtner was found along a roadside in Georgia in 1947. Nierembergia Ruiz & Pavon is a South American genus. Brugmansia suaveolens (Humboldt & Bonpland ex Willdenow) Sweet, also native to South America, was found in a ruderal yard (2001) and wooded ravine (1983) in Florida. Brugmansia has been treated as part of Datura, but it can be distinguished from that genus by its woody habit, pendulous flowers, and elongated, spineless fruits.

Since the early 1990s, our understanding of the circumscription of the Solanaceae, as well as phylogenetic relationships within the family, have been clarified using both morphological and molecular characters, particularly chloroplast DNA sequence data (W. G. D’Arcy 1991; A. T. Hunziker 2001; T. R. Martins and T. J. Barkman 2005; R. G. Olmstead and L. Bohs 2007; Olmstead and J. D. Palmer 1991, 1992; Olmstead et al. 1999, 2008; T. Särkinen et al. 2013). Based on molecular data, the family is considered monophyletic with the inclusion of Nolana Linnaeus f., Schizanthus, and Sclerophylax Miers. The subfamilies Solanoideae Burnett and Cestroideae Burnett, traditionally recognized on the basis of morphology alone, have been shown to be nonmonophyletic. Some generic concepts have been revised; changes relevant to the flora area are discussed under the various genera.

Selected References

None.

Lower Taxa

Alkekengi, Atropa, Bouchetia, Browallia, Calibrachoa, Calliphysalis, Capsicum, Cestrum, Chamaesaracha, Datura, Hunzikeria, Hyoscyamus, Jaborosa, Jaltomata, Leucophysalis, Lycianthes, Lycium, Nectouxia, Nicandra, Nicotiana, Oryctes, Petunia, Physalis, Quincula, Salpichroa, Schizanthus, Solanum

Illustrations

Solanaceae Illustrations

Key

1	Corollas campanulate, rotate, stellate, or urceolate; fruits berries (hardened or drupaceous in some Lycium).	> 2
2	Flowers and fruits borne in subumbellate, umbellate, or cymose clusters.	> 3
3	Flowers and fruits borne in umbellate clusters; anthers dehiscing longitudinally; calyces enlarged, with flaring lobes in fruit.	Jaltomata
3	Flowers and fruits borne in subumbellate or cymose clusters; anthers dehiscing by pores (sometimes expanding to longitudinal slits with age); calyces only slightly enlarged in fruit.	> 4
4	Shrubs; calyces 10-veined; leaves simple, margins entire.	Lycianthes (in part)
4	Herbs, vines, subshrubs, shrubs, or trees; calyces 5-veined; leaves simple or pinnately compound, margins entire, dentate, or lobed.	Solanum
2	Flowers and fruits solitary or in fascicles of 2–8.	> 5
5	Stems creeping (rooting at nodes); anthers dehiscing by pores.	Lycianthes (in part)
5	Stems erect, decumbent, prostrate, or scandent; anthers dehiscing by longitudinal slits.	> 6
6	Shrubs or scandent, perennial herbs; calyces not, or only sometimes, enlarged in fruit.	> 7
7	Scandent, perennial herbs; flowers and fruits solitary; corollas urceolate.	Salpichroa
7	Shrubs; flowers and fruits solitary or in fascicles of 2–8; corollas rotate, subrotate, or campanulate.	> 8
8	Plants without spines.	Capsicum
8	Plants spinescent.	Lycium (in part)
6	Herbs erect or decumbent, annual or perennial; calyces enlarged in fruit.	> 9
9	Corollas campanulate; calyx lobes enlarged and flaring in fruit, not enclosing berries.	Atropa
9	Corollas broadly campanulate, campanulate-rotate, rotate, or urceolate; calyx or calyx lobes enlarged in fruit and completely or partly enclosing berries.	> 10
10	Calyx lobes with sagittate to cordate bases, lobes expanded and surrounding berries.	Nicandra
10	Calyx lobes without lobed bases, basal portions expanded and com­pletely or partially enclosing berries.	> 11
11	Plants sparsely to densely covered with stalked, white vesicles.	Quincula
11	Plants glabrous or pubescent with simple or branched hairs.	> 12
12	Stems erect, usually unbranched; corollas white, lobed; fruiting calyces drying orange-red or bright red, inflated and completely enclosing berries.	Alkekengi
12	Stems erect to ascending or decumbent to prostrate, branched; corollas white, cream, yellow, greenish, or deep purple, unlobed or with obscure or shallow lobes or teeth; fruiting calyces drying brown, enlarged or inflated and completely or partially enclosing berries.	> 13
13	Flowers and fruits solitary; fruiting calyces inflated and completely enclosing berries.	Physalis
13	Flowers and fruits borne singly or in fascicles of (1–)2–6; fruiting calyces expanded but not inflated, mostly or completely enclosing berries.	> 14
14	Stems decumbent to ± prostrate; fruiting calyces shorter than berries; berries dry.	Chamaesaracha
14	Stems erect to ascending; fruiting calyces just shorter than or exceeding berries; berries fleshy.	> 15
15	Corollas broadly campanulate; stamens slightly unequal; fruiting calyces enclosing berries; seeds intermixed with sclerotic granules.	Calliphysalis
15	Corollas rotate; stamens equal; fruiting calyces shorter than or just exceeding berries; seeds not intermixed with sclerotic granules.	Leucophysalis
1	Corollas funnelform, salverform, or tubular; fruits capsules or berries (hardened or drupaceous in some Lycium).	> 16
16	Plants woody (subshrubs, shrubs, small trees, or lianas).	> 17
17	Shrubs, spinescent.	Lycium (in part)
17	Subshrubs, shrubs, small trees, or lianas, without spines.	> 18
18	Inflorescences axillary panicles; fruits berries.	Cestrum
18	Inflorescences axillary or terminal cymes, racemes, glomerules, or solitary flowers; fruits capsules.	> 19
19	Shrubs or small trees, 0.2–6(–10) m; stamens 5, inserted near base of corolla.	Nicotiana (in part)
19	Shrubs or subshrubs to 1.5 m; stamens 4 (5th much reduced or absent), inserted in distal half of corolla.	> 20
20	Corollas 5-lobed or sometimes appearing 4-lobed due to fusion of 2 abaxial lobes; capsules 2-valved; seeds prismatic or rounded on back and excavated ventrally.	Browallia (in part)
20	Corollas 5-lobed; capsules 4-valved; seeds reniform and finely wrinkled.	Hunzikeria
16	Plants herbaceous.	> 21
21	Corollas bilaterally symmetric (or slightly bilateral); fruits capsules.	> 22
22	Leaf margins usually deeply pinnately dissected or coarsely toothed or lobed.	> 23
23	Leaf margins coarsely toothed to shallowly lobed; corolla lobes shorter than to as long as tube; capsules circumscissile.	Hyoscyamus
23	Leaf margins pinnate-pinnatifid; corolla lobes longer than tube and often deeply dissected; capsules septicidal.	Schizanthus
22	Leaf margins entire or irregularly crenate or undulate.	> 24
24	Stems erect; stamens 5.	Nicotiana (in part)
24	Stems erect to ascending, decumbent, or procumbent; stamens 4, sometimes with reduced or sterile 5th.	> 25
25	Stems sprawling or procumbent; corollas funnelform; calyces not accrescent; capsules hemispheric, 2-valved.	Calibrachoa
25	Stems erect or ascending to decumbent; corollas funnelform or salver­form; calyces accrescent; capsules ellipsoid or ovoid, 2- or 4-valved.	> 26
26	Corollas funnelform; capsules ellipsoid, 4-valved.	Bouchetia
26	Corollas salverform; capsules ovoid, 2-valved.	Browallia (in part)
21	Corollas radially symmetric; fruits capsules or berries.	> 27
27	Corollas funnelform with 5 long-acuminate lobes; fruits 4-valved or irregularly dehiscing capsules, sometimes with prickles or tubercles.	Datura
27	Corollas funnelform, salverform, or tubular, lobes not long-acuminate; fruits berries or 2–4-valved capsules, not prickly.	> 28
28	Plants glabrous.	> 29
29	Plants prostrate to ascending; inflorescences solitary or fascicled flow­ers; corolla lobes acute to acuminate; fruits berries.	Jaborosa
29	Plants usually erect; inflorescences cymose, forming false racemes or glomerules; corolla lobes rounded to deltate; fruits capsules.	Nicotiana (in part)
28	Plants glandular-pubescent.	> 30
30	Stamens equal or slightly unequal; fruits berries.	> 31
31	Corollas salverform, with corona between tube and limb; berries nar­rowly ovoid, juicy.	Nectouxia
31	Corollas tubular; berries globose, dry.	Oryctes
30	Stamens unequal; fruits capsules.	> 32
32	Flowers and fruits in cymose clusters (appearing as false racemes or glomerules); calyx lobes deltate or triangular.	Nicotiana (in part)
32	Flowers and fruits solitary; calyx lobes linear.	Petunia