|
(Last Modified On 5/10/2013)
|
|
|
|
(Last Modified On 5/10/2013)
|
|
Genus
|
Petrea L.
|
|
PlaceOfPublication
|
Sp. P1. 626. 1753
|
|
Description
|
Shrubs, trees, or woody vines. Leaves decussate-opposite or whorled, decid- uous, exstipulate, pinnately net-veined, often roughened and with prominent venation. Inflorescences axillary or terminal, indeterminate (centripetal), race- mose, mostly elongate, many-flowered, often very handsome; bracts mostly small or absent, the bractlets and prophylls small, numerous, caducous. Flowers perfect, alternate on the rachis, often distant, each subtended by 1 or more prophylls, the receptacle swollen; calyx mostly regular, the tube cylindric or campanulate, mostly ribbed, membranous during anthesis, normally 5-lobed, the lobes mostly equal, blue or violet to purple or white, mostly longer than the tube, alternate with the corolla-lobes, bearing ventrally at the base of the lobes a thin-membranous, cali- cinal crest either in the form of a narrow sinuate or 5-toothed coronet or, if 5-cleft to the base, the divisions alternate with the calyx-lobes, erect during anthesis; corolla hypocrateriform, mostly darker blue or darker purple than the calyx or white, mostly slightly irregular, the tube cylindric, urceolate, or infundibular, the basal portion mostly narrow, the upper portion mostly abruptly and widely ampliate, the limb rotate, 5-lobed, the lobes mostly of 2 sizes, the anterior largest or rarely of 3 sizes with the 2 posterior smallest, mostly much shorter than the calyx-lobes and alternate with them, the posterior outside in prefloration; stamens 4, didynamous, inserted close together near the middle of the corolla-tube, in- cluded by the tube, the filaments short and slender, the anthers oblong or ovate, dorsifixed near the base, 2-thecate, each theca dehiscing by a longitudinal slit, introrse, the connective mostly enlarged, often surpassing the thecae; staminode present or absent; gynoecium compound but 1-carpelled through the abortion of 1 carpel, included in the corolla-tube; ovary subglobose or oblong, borne on a more or less conspicuous disk, more or less completely 2-loculed, the ovules 1 per locule, lateral, ascending, hemi-anatropous or imperfectly anatropous, or pendent and orthotropous; the style terminal, the stigma capitate, mostly oblique, more or less distinctly bilobed. Fruits drupaceous, completely enclosed by the mature calyx, the exocarp leathery or fleshy, the endocarp hard, more or less completely 2-loculed, forming 2 pyrenes, not easily separating, each pyrene 1-seeded, or by abortion the fruit with 1, 1-seeded pyrene; seeds laterally or apically attached, lacking endosperm; fruiting-calyx incrassate, the tube not much accrescent, mostly losing its blue color but becoming hard and tough and mostly plicate-ribbed, the lobes greatly accrescent, stiffened, reticulate-veined, papery, divergent, acting as wings for floating the fruit, the calicinal crest callose, mostly curving inwards and converging, completely closing the mouth of the calyx-tube.
|
|
Habit
|
Shrubs, trees, or woody vines
|
|
Distribution
|
A handsome genus of 41 species and infraspecific entities, widespread in tropical America from Cuba through the West Indies and from northern Mexico through Central America to southern Brazil, some taxa are naturalized in parts of Indonesia. Several species are widely cultivated for ornament. Fossils are known from the Eocene and Miocene of Europe and California.
|
|
Key
|
a. Leaf-blades becoming deeply bullate above when mature, the venation deeply impressed above and sharply prominent beneath. b. Calyx and corolla violet or blue ...... 1. P. rugosa var. rugosa bb. Calyx and corolla white ...... la. P. rugosa var. casta aa. Leaf-blades not conspicuously bullate above when mature, venation not sharply or con- spicuously prominent beneath. c. Calyx-tube glabrescent or nearly so. d. Calyx and corolla blue or lavender to violet or purple ...... 2. P. aspera f. aspera dd.Calyx and corolla white ...... 2a. P. aspera f. albiflora cc. Calyx-tube densely spreading-hirsute or tomentose. e. Leaf-blades glabrous or subglabrous beneath ...... 3. P. volubilis var. volubilis ee. Leaf-blades more or less densely pubescent beneath ...... 3a. P. volubilis var. pubescens
|
|
Tag
|
|
|
|
Project Name
|
|
Tag
|
|
|
|