Sp. Pl. 1: 177. 1753.
Gen. Pl. ed. 5, 82. 1754.
Herbs, perennial [annual], often suffrutescent, glabrous or pubescent, sometimes viscid; taproots slender and ropelike to swollen and tuberous. Stems erect to decumbent, unarmed, without glutinous bands on internodes. Leaves petiolate or sessile, ± equal in each pair; blade thin to thick and fleshy, base ± symmetric. Inflorescences terminal and axillary, terminating in pedunculate involucres subtending 1–16 flowers, usually cymose, sometimes consisting of single involucre in leaf-axil; bracts persistent, 5, connate or, rarely, distinct, ± ovate, forming weakly to strongly accrescent, herbaceous to papery involucre. Flowers bisexual, chasmogamous and/or cleistogamous; cleistogamous perianth small dome atop basal portion; chasmogamous perianth radially symmetric or slightly bilaterally symmetric, campanulate to funnelform, constricted beyond ovary, tube gradually to abruptly expanded, limb 5-lobed; stamens 3–6, exserted; styles exserted beyond stamens; stigmas capitate. Fruits radially symmetric, with (4–) 5 round or angular ribs separated by usually broad sulci, or ribs not well defined or not evident, obovoid, ellipsoid, or nearly globose, smooth or tuberculate, stiffly coriaceous, glabrous or pubescent, without glands.
Temperate and tropical regions, primarily North America and South America, at least one species indigenous to s Asia, Mirabilis jalapa worldwide
Species ca. 60 (21 in the flora).
Mirabilis is the most speciose genus of the Nyctaginaceae. A. Heimerl (1934c), in part adapting J. D. Hooker’s (1880) treatment, recognized six sections, five of which occur in the flora. P. C. Standley (1918) recognized segregate genera within the alliance, collapsing them into a broadly circumscribed Mirabilis in 1931. Species-level taxonomy is often equivocal because of the lack of distinguishing reproductive characteristics among forms that are, overall, morphologically and ecologically different. Problems are exacerbated in sect. Oxybaphus by autogamy, xenogamy, perennial nature, and rather high chromosome numbers (R. W. Cruden 1973; R. Spellenberg 1998). Some species are used widely for dyes, cosmetics, food, and medicine (G. M. Hocking 1997; D. J. Mabberly 1997).
|1||Fruits weakly ribbed, or bluntly 5-angled round in cross section, ovoid or ellipsoid, 2.5-12 mm||> 2|
|1||Fruits prominently 5-ribbed, ± obovoid, sometimes narrowly so and tapering at both ends, 3-6 mm||> 11|
|2||Flowers 6-16 per involucre; perianth 1.2-6 cm [7b. Mirabilis sect. Quamoclidion]||> 3|
|2||Flowers 1-3 per involucre; perianth 0.5-17 cm||> 7|
|3||Perianth usually creamy white; involucres pendant on peduncles; leaves strongly ascending||Mirabilis pudica|
|3||Perianth usually pink or magenta; involucres usually erect; leaves spreading||> 4|
|4||Bracts of involucres distinct or to 50% connate; perianth bell-shaped, 1.5-1.8 cm; fruits rugulose||Mirabilis alipes|
|4||Bracts of involucres at least 50% connate; perianth funnelform, 1.5-6 cm; fruits smooth, tuberculate, or rugulose||> 5|
|5||Perianth 1.5-2.5 cm; involucres 13-23 mm||Mirabilis macfarlanei|
|5||Perianth 2.5-6 cm; involucres 26-40 mm||> 6|
|6||Fruits bluntly 5-angled in cross section||Mirabilis greenei|
|6||Fruits ovoid or globose, not angled in cross section||Mirabilis multiflora|
|7||Fruits round or bluntly 5-angled in cross section; perianth (2-)3.5-17 cm, long- funnelform; flowers 1 per involucre [7a. Mirabilis sect. Mirabilis]||> 8|
|7||Fruits circular in cross section; perianth 0.5-1.8 cm, short funnelform; flowers 1-3 per involucre [7c. Mirabilis sect. Oxybaphoides]||> 9|
|8||Perianth 2-5 cm, usually rose-pink, sometimes yellow or variegated, or white, usually not pubescent; leaf base cordate to obtuse||Mirabilis jalapa|
|8||Perianth 7-17 cm, white, pubescent externally; leaf base usually cordate||Mirabilis longiflora|
|9||Involucres 3-flowered; perianth usually pink or purplish pink, rarely white||Mirabilis oxybaphoides|
|9||Involucres 1(-2)-flowered; perianth white, pink, or purplish pink||> 10|
|10||Lobes of involucres narrowly lance-oblong; involucres 7-16 mm; peri- anth white, rarely pale pink||Mirabilis tenuiloba|
|10||Lobes of involucres triangular to triangular-lanceolate; involucres 3-7 mm; perianth white, pink, or purple||Mirabilis laevis|
|11||Involucres not or only slightly accrescent after anthesis, greenish at maturity, opaque, moderately veiny, widely bell-shaped, 4-8 mm in fruit; perianth bright red-purple; leaf blades linear [7d. Mirabilis sect. Mirabilopsis]||Mirabilis coccinea|
|11||Involucres strongly accrescent after anthesis, becoming tan, translucent, prominently net-veined, very widely bell-shaped or rotate, 4-15 mm in fruit; perianth white, pink, or bright purple-pink; leafblades linear, linear-lanceolate or ovate [7e. Mirabilis sect. Oxybaphus]||> 12|
|12||Fruits usually glabrous, sometimes very lightly puberulent||Mirabilis glabra|
|12||Fruits puberulent or pubescent, sometimes sparsely so||> 13|
|13||Leaf blades linear to linear-lanceolate, mostly 0.1-1 cm wide (if slightly wider, then hairs of involucres with purple or black crosswalls); tubercles on fruits only slightly elevated above surface, low-rounded to round-angled, usually ± same color as background; ribs on fruit not bearing prominent tubercles||Mirabilis linearis|
|13||Leaf blades linear-lanceolate to ovate, mostly 1-8 cm wide (if leaf blades lanceolate, then hairs of involucres with pale crosswalls); tubercles on fruits markedly elevated above surface, prominently rounded or ± angular, often paler than background, or only slightly elevated above surface, low-rounded and same color as background; ribs sometimes bearing prominent tubercles||> 14|
|14||Stems hirsute; leaf blades broadly ovate, 3-6 cm wide||Mirabilis rotundifolia|
|14||Stems glabrous, puberulent, or spreading villous (if hirsute, then leaf blades linear-lanceolate or lanceolate); leaf blades linear-lanceolate to ovate, mostly 1-8 cm wide||> 15|
|15||Stems stiffly erect, little branched, 5-20 dm||> 16|
|15||Stems erect to decumbent, usually well branched, 0.8-15 dm||> 17|
|16||Fruits conspicuously pubescent, hairs 0.3-0.5 mm; stems densely puberulent distally with appressed, curved hairs; petioles 0.2-1 cm||Mirabilis gigantea|
|16||Fruits inconspicuously pubescent, hairs 0.1-0.5 mm; stems glabrous, glabrate, or sparsely glandular-pubescent; petioles 0.3- 2 cm.||Mirabilis austrotexana|
|17||Fruits densely glandular-puberulent, hairs 0.1 mm; ribs and sulci prominently tuberculate with tall, shelflike tubercles; bracts of involucres connate 90-100%||Mirabilis texensis|
|17||Fruits sparsely to densely pubescent, hairs 0.1-0.5 mm, hairs often tufted; ribs and sulci inconspicuously tuberculate or with tubercles tall, often shelflike; bracts of mature involucres connate 40-90%||> 18|
|18||Involucres green and blushed with dark violet or black; crosswalls of hairs on involucres and peduncles dark purple or black; leaf blades narrowly triangular-ovate to ovate, usually glabrous; perianth bright purple-pink||Mirabilis melanotricha|
|18||Involucres green or blushed with red; crosswalls of hairs on involucres and peduncles usually pale; leaf blades lanceolate to ovate, glabrous or pubescent; perianth white, pale pink, or bright purple-pink||> 19|
|19||Leaf blades linear-lanceolate to ovate or deltate, glabrous or pubescent; ribs of fruit notched, tuberculate, smooth, or somewhat rugose; sulci prominently or inconspicuously tuberculate; involucres in axils, loosely clustered on branches, or scattered in open, divaricate inflorescences, sparsely to densely pubescent||Mirabilis albida|
|19||Leaf blades lanceolate-triangular to ovate, usually glabrous; ribs of fruits usually irregularly notched, especially toward apex; sulci prominently tuberculate; involucres usually clustered at ends of branches, usually glabrous or glabrate, rarely villous||> 20|
|20||Leaf blades 1-4.5 cm wide; stems often sprawling across other vegetation, sparsely leafy, distally puberulent in 2 lines, puberulent over entire surface, or sometimes spreading viscid-villose||Mirabilis latifolia|
|20||Leaf blades 2-6.5 cm wide; stems usually erect or ascending, leafy, usually distally puberulent in 2 lines or glabrate, rarely spreading viscid-pilose||Mirabilis nyctaginea|
"thin" is not a number.