11. Nelumbonaceae Dumortier
John. H. Wiersema
Herbs , perennial, aquatic, rhizomatous; roots adventitious; air chambers conspicuous in vegetative portions of plant. Rhizomes branched, repent, slender, terminal portions becoming tuberous-thickened late in growing season. Leaves arising directly from rhizome, alternate, floating or emersed; petiole long. Leaf blade peltate, orbiculate, margins entire; laticifers present. Inflorescences axillary, solitary flowers. Flowers bisexual, protogynous, diurnal, borne above water surface; peduncle long; involucre absent; perianth not persistent in fruit (outermost tepals of N . lutea normally persistent), hypogynous; tepals numerous, distinct, outermost reduced, inner tepals becoming larger and more petaloid; stamens numerous; filaments slender; anthers dehiscing by longitudinal slits, connective appendage incurved; pistils numerous, 1-carpellate, separately embedded in flattened top of turbinate receptacle; ovary 1-locular; placentation apical; ovule 1; style short; stigma nearly sessile, capitate. Fruits nutlike, indehiscent, loose in cavities of strongly accrescent receptacle. Seed 1, aril absent; endosperm and perisperm absent; embryo completely filling seed; cotyledons 2, fleshy.
Genus 1, species 2 (2 in the flora): temperate and tropical regions.
Nelumbonaceae are pollinated by insects, often by beetles.
Formerly Nelumbonaceae frequently have been included in Nymphaeaceae in the broad sense.
Wood, C. E. Jr. 1959. The genera of the Nymphaeaceae and Ceratophyllaceae in the southeastern United States. J. Arnold Arbor. 40: 94-112.