The Families of Flowering Plants
The Families of Flowering Plants | |
Alternatively Hippocrateaceae Juss.
Including Chingithamnaceae Hand.-Mazz., Leptolobaceae Dulac, Pottingeriaceae (A. Engler) Takhtajan (doubtfully), Salaciaceae, Tripterygiaceae
Excluding Canotiaceae, Goupiaceae, Lophopyxidaceae, Siphonodontaceae
Habit and leaf form. Trees, shrubs, and lianas; laticiferous, or non-laticiferous and without coloured juice. ‘Normal’ plants (usually), or switch-plants. Leaves well developed (mostly), or much reduced (e.g. Psammomoya, with leaves represented by cataphylls). Self supporting, or climbing; when climbing, stem twiners (e.g. Hippocratea). Leaves alternate, or opposite; ‘herbaceous’, or leathery, or membranous (?); petiolate; non-sheathing; simple. Lamina entire; pinnately veined; cross-venulate. Leaves stipulate (stipules small), or exstipulate. Stipules when present, caducous. Leaves without a persistent basal meristem. Domatia occurring in the family (in one genus); manifested as pits.
General anatomy. Plants with laticifers, or without laticifers. The laticifers when present, in stems, or in leaves and in stems.
Leaf anatomy. Mucilaginous epidermis present, or absent.
Lamina with secretory cavities, or without secretory cavities (?). The mesophyll with sclerencymatous idioblasts, or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Euonymus, Maytenus).
Stem anatomy. Secretory cavities present, or absent (?). Cork cambium present; initially deep-seated, or superficial. The cortex containing cristarque cells, or without cristarque cells. Nodes unilacunar. Internal phloem absent. Secondary thickening developing from a conventional cambial ring, or anomalous; when anomalous, via concentric cambia (e.g. Salacia). ‘Included’ phloem present, or absent. Xylem with tracheids, or without tracheids; with fibre tracheids, or without fibre tracheids; with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls scalariform, or simple (usually). Vessels without vestured pits. Wood parenchyma apotracheal, or paratracheal.
Reproductive type, pollination. Plants hermaphrodite (usually), or monoecious, or dioecious. Pollination entomophilous.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes, or in fascicles. The terminal inflorescence unit cymose (usually), or racemose (rarely). Inflorescences terminal, or axillary, or epiphyllous (Polycardia); mostly cymes or fascicles. Flowers usually small; regular; 4–5 merous; cyclic; nearly always tetracyclic. Hypogynous disk usually present; intrastaminal; annular.
Perianth with distinct calyx and corolla; (4–)8–10; 2 whorled; isomerous. Calyx (2–)4–5; 1 whorled; polysepalous, or gamosepalous (basally); regular; imbricate, or valvate (rarely). Corolla (2–)4–5; 1 whorled; polypetalous; imbricate, or valvate; regular; not fleshy.
Androecium (2–)3, or (4–)5. Androecial members free of the perianth; free of one another, or coherent (sometimes connate at the base); when joined 1 adelphous; 1 whorled (usually), or 2 whorled. Androecium exclusively of fertile stamens (usually), or including staminodes. Staminodes sometimes (2–)3–5 (alternating with the stamens); internal to the fertile stamens; non-petaloid. Stamens (2–)3–5; isomerous with the perianth; oppositisepalous. Anthers dehiscing via longitudinal slits; extrorse, or introrse; unilocular to bilocular; bisporangiate, or tetrasporangiate. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or decussate. Anther wall initially with more than one middle layer. Tapetum glandular. Pollen shed in aggregates (often), or shed as single grains; when in aggregates in tetrads, or in polyads. Pollen grains aperturate; 3 aperturate; colporate; 2-celled, or 3-celled.
Gynoecium 2–5 carpelled (usually with all but one abortive). The pistil 1–5 celled. Gynoecium syncarpous; synovarious to eu-syncarpous; superior, or partly inferior (rarely). Ovary plurilocular; 2–5 locular. Gynoecium stylate, or non-stylate. Styles 1; attenuate from the ovary; apical. Stigmas 2–5 (same number as G); dry type; non-papillate; Group II type. Placentation axile. Ovules (1–)2 per locule (usually), or 3–50 per locule (rarely many); pendulous, or ascending; apotropous; with ventral raphe, or with dorsal raphe (when pendulous); often arillate; anatropous; bitegmic; tenuinucellate, or crassinucellate. Outer integument contributing to the micropyle, or not contributing to the micropyle. Endothelium differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; usually ephemeral. Synergids pear-shaped, or hooked (with filiform apparatus in (e.g.) Hippocratea). Endosperm formation nuclear. Embryogeny caryophyllad, or solanad.
Fruit fleshy, or non-fleshy; dehiscent, or indehiscent; a capsule, or capsular-indehiscent, or a berry, or a drupe, or a samara, or achene-like. Capsules loculicidal. Seeds endospermic (usually), or non-endospermic. Endosperm when present, ‘more or less’ oily. Seeds with a testa; winged, or wingless. Embryo well differentiated. Cotyledons 2; flat (large, foliaceous). Embryo chlorophyllous (3/19); straight.
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Not cyanogenic. Alkaloids present (commonly), or absent. Iridoids not detected. Proanthocyanidins present (usually), or absent; when present, cyanidin and delphinidin. Flavonols present, or absent (Salacia); kaempferol and quercetin (mostly), or myricetin (Catha). Ellagic acid absent (9 species, 5 genera). Arbutin absent. Saponins/sapogenins present, or absent. Aluminium accumulation demonstrated (rarely). Sugars transported as oligosaccharides + sucrose, or as sugar alcohols + oligosaccharides + sucrose. C3 (?), or CAM. CAM recorded directly in Gymnosporia (non-succulent, and dubious).
Geography, cytology. Sub-tropical and tropical (most), or temperate (fewer). Cosmopolitan.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Santaliflorae; Celastrales. Cronquist’s Subclass Rosidae; Celastrales. APG (1998) Eudicot; core Eudicot; Rosid; Eurosid I; unassigned at ordinal level. Species 850. Genera about 85; Allocassine, Anthodon, Apatophyllum, Apodostigma, Arnicratea, Baequaertia, Bhesa, Brassiantha, Brexiella, Campylostemon, Cassine, Catha, Celastrus, Cheiloclinium, Crossopetalum, Cuervea, Denhamia, Dicarpellum, Elachyptera, Elaeodendron, Empleuridium, Euonymus, Evonymopsis, Fraunhofera, Glyptopetalum, Goniodiscus, Gyminda, Hartogiella, Hartogiopsis, Hedraianthera, Helictonema, Herya, Hexaspora, Hippocratea, Hylenaea, Hypsophila, Kokoona, Loeseneriella, Lophopetalum, Maurocenia, Maytenus, Menepetalum, Microtropis, Monimopetalum, Mortonia, Moya, Myginda, Nicobariodendron, Orthodphenia, Paxistima, Peripterygia, Peritassa, Perottetia, Platypterocarpus, Plenckia, Pleurostylia, Polycardia, (Pottingeria?), Prionostemma, Pristimera, Psammomoya, Pseudosalacia, Ptelidium, Pterocelastrus, Putterlickia, Quetzalia, Reissantia, Rzedowskia, Salacia, Salacighia, Salaciopsis, Salvadoropsis, Sarawakodendron, Schaefferia, Semialarium, Simicratea, Simirestis, Tetrasiphon, Thyrsosalacia, Tontelea, Torralbasia, Tripterygium, Tristemonanthus, Viposia, Wimmeria, Xylonymus, Zinowiewia.
Economic uses, etc. A few genera cultivated as ornamentals (e.g. Catha, Celastrus, Elaeodendron, Euonymus). The toxic alkaloid maytansine (from Maytenus), when delivered by antibodies, may have application in treating colon cancers (New Scientist 31 August 1996).
Illustrations. • Euonymus europaeus. • Technical details (Euonymus). • Technical details, from Thonner (Elaeodendron). • Technical details, from Thonner (Salacia). • Technical details, from Lindley (Hippocratea).
This description is offered for casual browsing only. We strongly advise against extracting comparative information from it. This is much more easily achieved using 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 specified attributes, summaries of attributes within groups of taxa, geographical distribution, genera included in each family, classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG), and notes on the APG classification.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 10th April 2008. http://delta-intkey.com’.
