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Nymphaeaceae is a family of flowering plants. Members of this family are commonly called water lilies and live as rhizomatous aquatic herbs in temperate and tropical climates around the world. The family contains eight large-flowered genera with about 70 species.〔()〕 The genus ''Nymphaea'' contains about 35 species in the Northern Hemisphere.〔 The genus ''Victoria'' contains two species of giant water lilies endemic to South America.〔 Water lilies are rooted in soil in bodies of water, with leaves and flowers floating on the surface. The leaves are round, with a radial notch in ''Nymphaea'' and ''Nuphar'', but fully circular in ''Victoria''. Water lilies are a well studied clade of plants because their large flowers with multiple unspecialized parts were initially considered to represent the floral pattern of the earliest flowering plants, and later genetic studies confirmed their evolutionary position as basal angiosperms. Analyses of floral morphology and molecular characteristics and comparisons with a sister taxon, the family Cabombaceae, indicate, however, that the flowers of extant water lilies with the most floral parts are more derived than the genera with fewer floral parts. Genera with more floral parts, ''Nuphar'', ''Nymphaea'', ''Victoria'', have a beetle pollination syndrome, while genera with fewer parts are pollinated by flies or bees, or are self- or wind-pollinated.〔Phylogeny, Classification and Floral Evolution of Water Lilies (Nymphaeaceae; Nymphaeales): A Synthesis of Non-molecular, rbcL, matK, and 18S rDNA Data, Donald H. Les, Edward L. Schneider, Donald J. Padgett, Pamela S. Soltis, Douglas E. Soltis and Michael Zanis, Systematic Botany, Vol. 24, No. 1, 1999, pp. 28-46〕 Thus, the large number of relatively unspecialized floral organs in the Nymphaeaceae is not an ancestral condition for the clade. Horticulturally water lilies have been hybridized for temperate gardens since the nineteenth century, and the hybrids are divided into three groups: hardy, night-blooming tropical, and day-blooming tropical water lilies. Hardy water lilies are hybrids of ''Nymphaea'' species from the subgenus ''Castalia''; night-blooming tropical water lilies are developed from the subgenus ''Lotos''; and the day-blooming tropical plants arise from hybridization of plants of the subgenus ''Brachyceras''.〔Evolution of garden Nymphaeas, G. V. Subrahmanyam and T. N. Khoshoo, Current Science, 53(7), 360-363, 1984〕〔Nymphaeaceae, Nymphaea belophylla Trickett: New state record, Gisaine de Andrade Amador, Geraldo Alves Damasceno-Júnior,, Rosa Helena da Silva, Arnildo Pott and Vali Joana Pott, Check List 9(2): 440–442, 2013〕 ==Description== The Nymphaeaceae are aquatic, rhizomatous herbs. The family is further characterized by scattered vascular bundles in the stems, and frequent presence of latex, usually with distinct, stellate-branched sclereids projecting into the air canals. Hairs are simple, usually producing mucilage (slime). Leaves are alternate and spiral, opposite or occasionally whorled, simple, peltate or nearly so, entire to toothed or dissected, short to long petiolate), with blade submerged, floating or emergent, with palmate to pinnate venation. Stipules are either present or absent. Flowers are solitary, bisexual, radial, with a long pedicel and usually floating or raised above the surface of the water, with girdling vascular bundles in receptacle. Sepals are 4-12, distinct to connate, imbricate, and often petal-like. Petals lacks or 8 to numerous, inconspicuous to showy, often intergrading with stamens. Stamens are 3 to numerous, the innermost sometimes represented by staminodes. Filaments are distinct, free or adnate to petaloid staminodes, slender and well differentiated from anthers to laminar and poorly differentiated from anthers; pollen grains usually monosulcate or lacking apertures. Carpels are 3 to numerous, distinct or connate. Fruit is an aggregate of nuts, a berry, or an irregularly dehiscent fleshy capsule. Seeds are often arillate, more or less lacking sperm. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nymphaeaceae」の詳細全文を読む スポンサード リンク
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