Nymphaea L., nom. cons.

Perennial herbs. Rhizomes usually stoloniferous, erect or creeping, sometimes branched, hairy in interfoliar region, with leaves, vegetative buds and flowers arranged in spirals. Leaves polymorphic, long-petiolate; juvenile leaves membranous, at first subulate, hastate, sagittate, deltoid or cordate-ovate and submerged, afterwards elliptic and cleft up to petiole-base and floating; adult leaves coriaceous, prominently venose beneath, broadly elliptic to orbicular and deeply cleft near or up to petiole-base, floating or rarely emersed. Flowers on long peduncles, floating or emersed, showy. Sepals 4, free, hypogynous. Petals numerous, hypogynous to perigynous, a few outermost ones sometimes sepaloid, innermost ones often transitional to stamens. Stamens numerous, inflexed, perigynous, dorsiventrally flattened with or without distal sterile appendages, outer stamens with broad, petaloid filaments and reduced anthers, the inner with narrower filaments and longer anthers; anther-sacs partially sunken. Carpels 5 - 35, partially (septa double) or fully (septa single) coherent, fused peripherally, arranged radially around and adnate below to central core of receptacular tissue to about half their length, with a cup-shaped depression above formed by radiating, curvate, bilobed stigmas with or without an appendage. Ovules numerous, arising all over septa. Berry globose, often crowned with persistent, green filaments, retracted to and ripening under water. Seeds enclosed in bell-shaped aril, indurate.

Tropical and temperate regions inhabiting stagnant freshwater ponds, lakes and swamps; ca 50 species, 6 species in India. Besides, a few exotics are cultivated in ponds and lakes.

Literature. CONARD, H.S. (1905). The waterlilies: a monograph of the genus Nymphaea. Carnegie Inst Wash. Publ. 4: 1 - 279, tt. 1 - 30.

KEY TO THE SPECIES

1a. Leaves distinctly subpeltate; primary veins prominently raised beneath

2

b. Leaves cleft to petiole-base, non-peltate; primary veins impressed beneath

4

2a. Leaves glabrous; sepals obscurely veined, persistent in fruit; stamens with distal sterile appendage

3. Nymphaea nouchali

b. Leaves velutinous pubescent beneath; sepals conspicously veined, decaying after flowering; stamens without sterile appendages

3

3a. Flowers white or a few sepals and outer petals with a tinge of purple towards apex outside; anthers yellow; filaments of inner stamens without purplish band outside

4. Nymphaea pubescens

b. Flowers crimson red; anthers red; filaments of inner stamens with a purplish band outside

5. Nympbaea rubra

4a. Rhizomes 2.5 - 7 cm long, erect, densely clothed with black hairs; leaves 3 - 7 cm across; petioles ca 1.5 mm across,filiform; sepals accrescent in fruit

6. Nympbaea tetragona

b. Rhizomes much longer than 7 cm, horizontally creeping; interfoliar hairs not black; leaves 10 - 28 cm across; petioles 3 - 10 mm across; sepals not accrescent in fruit

5

5a. Flower buds obtuse at apex; receptacle cylindrical; sepals as long as or shorter than petals; filaments of innermost stamens filiform, narrower than anthers; stigma almost flat

1. Nympbaea alba

b. Flower buds acute at apex; receptacle weakly tetragonous; sepals longer than petals; filaments of innermost stamens lanceolate, never narrower than anthers; stigma strongly concave

2. Nymphaea candida

List of Lower Taxa