Passifloraceae Juss.
Including Modeccaceae J.G. Agardh, Paropsiaceae Dum.
Habit and leaf form. Trees and shrubs, or lianas (and herbaceous climbers); non-laticiferous and without coloured juice. Self supporting, or climbing; the climbers tendril climbers (the tendrils axillary, perhaps representing modified inflorescences). Mesophytic, or xerophytic. Leaves alternate; spiral; petiolate; non-sheathing; simple, or compound (e.g. in Deidamia, Passiflora); when compound, palmate. Lamina when simple dissected, or entire; when dissected, palmatifid; pinnately veined, or palmately veined; cross-venulate. Leaves stipulate, or exstipulate. Stipules when present, free of one another; usually small, caducous. Leaves without a persistent basal meristem.
Leaf anatomy. Extra-floral nectaries present (on the petioles). Mucilaginous epidermis present, or absent. Stomata anomocytic.
The mesophyll with sclerencymatous idioblasts, or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Passiflora).
Stem anatomy. Nodes tri-lacunar. Internal phloem absent. Secondary thickening developing from a conventional cambial ring (?), or anomalous; in Adesmia, via concentric cambia. ‘Included’ phloem present, or absent (?). Xylem with fibre tracheids; with libriform fibres, or without libriform fibres. Vessel end-walls simple, or scalariform and simple. Wood parenchyma typically apotracheal. Sieve-tube plastids S-type.
Reproductive type, pollination. Plants hermaphrodite (usually), or dioecious (e.g. in Adenia), or polygamomonoecious (?). Entomophilous.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; in cymes. The terminal inflorescence unit cymose. Inflorescences axillary. Flowers usually three bracteate; large; regular; (3–)5(–8) merous; cyclic. Floral receptacle developing an androphore (often), or with neither androphore nor gynophore; markedly hollowed (often), or not markedly hollowed (the receptacle variously shaped). Free hypanthium present (usually), or absent. Hypogynous disk often present (staminodial), or absent.
Perianth with distinct calyx and corolla, or sepaline (C rarely lacking); 5, or 6–16; usually 2 whorled; isomerous. Calyx (3–)5(–8); 1 whorled; polysepalous, or gamosepalous (basally); regular; persistent; imbricate. Corolla (3–)5(–8); 1 whorled; appendiculate (with a conspicuous staminodal ‘corona’, this consisting of threadlike filaments or scales, or annular); polypetalous, or gamopetalous (the petals sometimes shortly united basally). Corolla lobes markedly longer than the tube. Corolla imbricate; regular.
Androecium 5, or 20–60. Androecial members free of the perianth; united with the gynoecium (at least, often inserted on the gynophore), or free of the gynoecium; free of one another, or coherent; sometimes 1 adelphous (the stamens of Androsiphonia connate around the gynophore); 1 whorled (?—when staminodes absent), or 2 whorled, or 3 whorled. Androecium including staminodes (always?). Staminodes 15–50 (usually ‘many’ atop the hypanthium within the corolla, constituting the conspicuous petaloid ‘corona’, or of filaments, or sometimes represented by a disk around the gynoecium); external to the fertile stamens, or in the same series as the fertile stamens, or internal to the fertile stamens; petaloid, or non-petaloid, or petaloid and non-petaloid. Stamens (4–)5(–10); isomerous with the perianth, or diplostemonous. Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral. Anther wall initially with more than one middle layer. Tapetum glandular. Pollen grains aperturate; 3–12 aperturate; colporate (to colpoidorate); 2-celled.
Gynoecium (2–)3(–5) carpelled. Carpels reduced in number relative to the perianth to isomerous with the perianth. The pistil 1 celled. Gynoecium syncarpous; synovarious to eu-syncarpous; superior. Ovary 1 locular; stipitate. Styles 1, or (2–)3(–5); free to partially joined; apical. Stigmas 1, or (2–)3(–5); dry type; papillate, or non-papillate; Group II type. Placentation parietal. Ovules in the single cavity 7–100 (‘several to many’); arillate; orthotropous to anatropous; bitegmic; crassinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids hooked (sometimes with filiform apparatus). Endosperm formation nuclear. Embryogeny onagrad, or piperad (occasionally).
Fruit dehiscent, or indehiscent; a capsule, or a berry. Seeds endospermic. Endosperm ruminate (P. foetida), or not ruminate; oily. Embryo well differentiated. Cotyledons 2; flat. Embryo achlorophyllous (1/1); straight.
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Often cyanogenic, or not cyanogenic. Cynogenic constituents of the gynocardin group. Alkaloids present (commonly), or absent. Iridoids not detected. Proanthocyanidins absent. Flavonols absent. Ellagic acid absent (3 species of Passiflora). Saponins/sapogenins present, or absent. Aluminium accumulation not found. C3 and CAM. C3 physiology recorded directly in Passiflora. CAM recorded directly in Adenia.
Geography, cytology. Sub-tropical to tropical. Pantropical and subtropical. X = 6, 9–11.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Violiflorae; Violales. Cronquist’s Subclass Dilleniidae; Violales. APG (1998) Eudicot; core Eudicot; Rosid; Eurosid I; Malpighiales. Species 530. Genera about 18; Adenia, Ancistrothyrsus, Androsiphonia, Barteria, Basananthe, Crossostemma, Deidamia, Dilkea, Efulensia, Hollrungia, Mitrostemma, Paropsia, Paropsiopsis, Passiflora, Schlechterina, Smeathmannia, Tetrapathaea, Tryphostemma, Viridivia.
Economic uses, etc. Edible berries (‘passion fruit’) from Passiflora spp., cultivated ornamental climbers.
Illustrations. • Passiflora alata. • Technical details (Passiflora). • Technical details (Adenia).
Quotations
There has fallen a splendid tear
From the
passion-flower at the gate
(Tennyson, ‘Maud’)
Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).
