The families of flowering plants.
IncludingHibbertiaceae J.G. Agardh
Habit and leaf form. Trees, shrubs, and lianas, or herbs (a few). ‘Normal’ plants, or switch-plants (occasionally); switch plants with the principal photosynthesizing function transferred to stems. Leaves well developed (usually), or much reduced. With a basal aggregation of leaves (sometimes), or with neither basal nor terminal aggregations of leaves. Self supporting, or climbing; sometimes stem twiners; Hibbertia recorded as reversibly twining clockwise, or twining anticlockwise. Sometimes leptocaul. Mesophytic, or xerophytic. Leaves usually deciduous; alternate (usually), or opposite (rarely); usually spiral; leathery (often), or ‘herbaceous’, or membranous; petiolate; sheathing, or non-sheathing; gland-dotted, or not gland-dotted; simple. Lamina entire (usually), or dissected (occasionally lobed); one-veined, or pinnately veined, or palmately veined. Leaves stipulate (the stipules winglike, adnate to the petiole), or exstipulate. Lamina margins entire, or serrate. Leaves without a persistent basal meristem. Domatia occurring in the family (from two genera); manifested as pockets, or hair tufts.
General anatomy. Plants with ‘crystal sand’, or without ‘crystal sand’.
Leaf anatomy. Stomata anomocytic (usually), or paracytic (Tetracera).
The mesophyll with sclerencymatous idioblasts, or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Dillenia).
Stem anatomy. Cork cambium present; initially deep-seated (usually), or superficial. Nodes unilacunar, or tri-lacunar, or penta-lacunar to multilacunar (?). Internal phloem absent. Secondary thickening developing from a conventional cambial ring, or anomalous (rarely?); when anomalous, via concentric cambia (Doliocarpus). ‘Included’ phloem present (rarely?), or absent. Xylem with tracheids; with vessels. Vessel end-walls scalariform, or scalariform and simple. Vessels without vestured pits. Wood parenchyma predominantly apotracheal, or apotracheal and paratracheal (sometimes with a few cells around the vessels). Sieve-tube plastids S-type. Pith with diaphragms (occasionally), or without diaphragms.
Reproductive type, pollination. Fertile flowershermaphrodite. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’. The ultimate inflorescence unit (when flowers aggregated) cymose, or racemose. Flowers small to medium-sized (usually), or large; regular to somewhat irregular. The floral irregularity when noticeable, involving the androecium. Flowers partially acyclic. The perianth acyclic, or the androecium acyclic, or the perianth acyclic and the androecium acyclic. Floral receptacle not markedly hollowed. Free hypanthium absent. Hypogynous disk absent.
Perianthwith distinct calyx and corolla; (5–)10(–25). Calyx (3–)5(–20); polysepalous; fleshy, or non-fleshy; persistent; spirally imbricate. Corolla (2–)5; polypetalous; imbricate, or crumpled in bud (often); white, or yellow; deciduous (often conspicuously caducous). Petals bilobed, or entire.
Androecium 15–150 (usually), or 1–10 (rarely). Androecial members branched (usually — in that the numerous stamens often arise from 5–15 ‘trunks’), or unbranched; when numerous, maturing centrifugally (as a whole, or those within each cluster); free of the perianth; all equal to markedly unequal; free of one another, or coherent (often united basally); when clustered 1 adelphous, or 5–15 adelphous. Androecium exclusively of fertile stamens, or including staminodes. Stamens 1–10 (rarely), or 15–150 (usually ‘many’); reduced in number relative to the adjacent perianth to diplostemonous to polystemonous. Anthers usually basifixed, or adnate; dehiscing via pores to dehiscing via short slits (apically), or dehiscing via longitudinal slits; introrse, or latrorse; tetrasporangiate. Endothecium developing fibrous thickenings, or not developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or linear. Anther wall initially with more than one middle layer. Tapetum amoeboid, or glandular. Pollen grains aperturate; 2(–4) aperturate; colpate, or colporate, or rugate, or spiraperturate; 2-celled.
Gynoecium (1–)2–7(–20) carpelled. The pistil when syncarpous, (2–)5(–7) celled.Gynoecium apocarpous to syncarpous; eu-apocarpous to semicarpous (usually), or synovarious (rarely); superior. Carpel fully closed, or incompletely closed; stylate; apically stigmatic; 1–100 ovuled (i.e. to ‘many’). Placentation when apocarpous marginal, or basal. Ovary when syncarpous (2–)5(–7) locular. Styles as many as G; when carpels connate, free. Stigmas wet type; non-papillate; Group IV type. Placentation when syncarpous axile, or basal. Ovules when syncarpous, 1–20 per locule; ascending; apotropous; with ventral raphe; usually arillate; anatropous to amphitropous (with zigzag micropyle); 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 pear-shaped, or hooked (Hibbertia). Endosperm formation nuclear. Embryogeny onagrad.
Fruit non-fleshy; an aggregate, or not an aggregate. The fruiting carpel when apocarpous a follicle, or an achene, or baccate (?). Fruit when syncarpous dehiscent, or indehiscent (and then enclosed in the fleshy calyx); a capsule, or capsular-indehiscent; enclosed in the fleshy receptacle, or enclosed in the fleshy hypanthium, or without fleshy investment. Seeds copiously endospermic. Endosperm oily. Embryo well differentiated (very small). Cotyledons 2. Embryo achlorophyllous (1/1); straight.
Physiology, biochemistry. Not cyanogenic. Alkaloids absent (usually), or present (then not benzyl isoquinoline). Iridoids not detected. Proanthocyanidins present; cyanidin and delphinidin. Flavonols present; quercetin, or kaempferol, quercetin, and myricetin. Ellagic acid absent (3 species, 2 genera). Saponins/sapogenins absent. Aluminium accumulation not found. Sugars transported as sucrose, or as oligosaccharides + sucrose (in Dillenia). Anatomy non-C4 type (Dillenia).
Geography, cytology. Temperate (warm), or sub-tropical to tropical. Pantropical and subtropical, and all Australia. X = 4, 5, 8, 10, 12, 13.
Taxonomy.Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Malviflorae; Dilleniales. Cronquist’s Subclass Dilleniidae; Dilleniales. APG 3 core angiosperms; core eudicot; unplaced at Superordinal level; Order Dilleniales.
Species 400. Genera 11; Acrotrema, Curatella, Davilla, Didesmandra,Dillenia, Doliocarpus, Hibbertia, Pachynema, Pinzona,Schumacheria, Tetracera.