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~ Nymphaeaceae.
Habit and leaf form. Stemless aquatic herbs; laticiferous. Rhizomatous (the rhizomes villous). Hydrophytic; rooted. Leaves (blades) floating (on their long petioles). Leaves alternate; membranous; long petiolate; simple. Lamina entire; lanceolate to orbicular (sometimes violet beneath); cross-venulate; cordate. Leaves exstipulate. Lamina margins entire.
General anatomy. Plants with laticifers (articulated). The laticifers in leaves, in stems, in roots, in flowers, and in the fruits.
Leaf anatomy. The leaf lamina dorsiventral. Stomata mainly confined to one surface (the upper one); anomocytic. Foliar vessels absent.
Axial (stem, wood) anatomy. Primary vascular tissues consisting of scattered bundles (monocotyledon-like). Secondary thickening absent (the bundles closed). The axial xylem without vessels.
The axial xylem with tracheids (with spiral or annular thickenings).
Root anatomy. Root xylem without vessels.
Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers solitary (long-pedunculate but often not reaching the surface of the water, at least sometimes cleistogamous); extra-axillary; ebracteate (under the interpretation of the ‘perianth’ adopted here); ebracteolate; regular; more or less cyclic; polycyclic. Free hypanthium present (if the ‘calyx’ as described here is interpreted as an involucre of bracts, so that the ‘corolla tube’ becomes a hypanthium), or absent (if interpreted otherwise).
Perianth as interpreted here, with distinct calyx and corolla; 8–60 (?—to ‘many’); 4–5 whorled. Calyx 5; 1 whorled; polysepalous (borne beneath the ovary, the oblong sepals long-mucronate); regular. Corolla 12–50 (to ‘many’); lobes more or less distinctly 3–4 whorled (on the tube); gamopetalous; regular; persistent.
Androecium 30–60 (‘many’). Androecial members maturing centripetally; adnate (to the corolla tube); free of one another; (4–)5(–6) whorled (each series with about 10 members). Androecium including staminodes. Staminodes about (15–)20 (constituting the upper (outer) two series); external to the fertile stamens. Stamens about (20–)30; filantherous (with short filaments). Anthers basifixed; non-versatile; dehiscing via longitudinal slits; bilocular; tetrasporangiate. Pollen grains nonaperturate (with a reduced exine).
Gynoecium 8–14 carpelled (not immersed in the torus). The pistil 8–14 celled. Gynoecium syncarpous; eu-syncarpous; inferior (in that the corolla tube arises from around the top of the ovary). Ovary 8–14 locular. Gynoecium very shortly stylate. Styles 1; apical. Stigmas 1; forming an obscurely radiate disk with a central, conical projection. Placentation laminar, the ovules scattered over the partitions. Ovules 30–50 per locule (‘rather numerous’); over the carpel surface; non-arillate; orthotropous; bitegmic; crassinucellate. Endosperm formation cellular.
Fruit fleshy; indehiscent; a berry (globose, crowned by the persistent corolla, with sweet, rose coloured flesh); many seeded. Seeds endospermic. Perisperm present. Seeds densely, rather softly spinulose. Embryo well differentiated (minute). Cotyledons 2.
Physiology, phytochemistry. Not cyanogenic.
Geography, cytology. Paleotropical. Tropical. Indomalayan. N = 17, 18.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Nymphaeiflorae; Nymphaeales. Cronquist’s Subclass Magnoliidae; Nymphaeales. APG III peripheral angiosperms; Superorder Nymphaeanae. APG IV Order Nymphaeales (as a synonym of Nymphaeaceae).
Species 4. Genera 1; only genus Barclaya.
General remarks. If family names are intended to convey information of practical utility additional to supposed phylogeny, Barclaya is inappropriately included in Nymphaeaceae. Differences include the non-peltate leaves; the flowers not or scarcely opening (‘hydrocleistogamous’) and fully cyclic, without sequential morphological transitions from perianth to stamens; gamopetalous corolla, adnate androecium, non-petaloid staminodes, relatively few fertile stamens, basifixed anthers, non-aperturate pollen, fully inferior ovary, etc. The anatomical differences may be under-estimated here, because the Metcalfe and Chalk (1965) account of Nymphaeaceae sensu lato employed here does not permit satisfactory treatment of this sensu stricto family.
Illustrations. • Barclaya longifolia: Hook. Ic. Pl. 9 (1852).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 4th May 2024. delta-intkey.com’.
