Including Crescentiaceae Dum.
Habit and leaf form. Trees, or shrubs, or lianas, or herbs (rarely). Self supporting, or climbing; when climbing stem twiners, or tendril climbers (via modified terminal leaflets), or root climbers. Leaves opposite (mostly), or whorled, or alternate (rarely, then spiral); petiolate; non-sheathing; compound (usually), or simple; pinnate, or palmate, or bipinnate, or multiply compound. Lamina when simple dissected, or entire; when dissected pinnatifid, or palmately lobed. Leaves exstipulate; without a persistent basal meristem. Domatia recorded (14 genera); represented by pits (rarely), or pockets, or hair tufts.
Leaf anatomy. Stomata present; anomocytic, or paracytic, or diacytic (Kigelia).
The mesophyll with sclerencymatous idioblasts (spicular cells), or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Catalpa, Jacaranda, Tecomella).
Stem anatomy. Cork cambium present; initially deep-seated, or superficial. Nodes unilacunar (3 to several traces). Cortical bundles absent. Medullary bundles present (inversely orientated, e.g. in Campsis, Tecoma), or absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring, or anomalous; via concentric cambia (e.g. Campsis,Clytostoma, Tecomaria, where a second series of bundles forms internally to the primary cylinder, in the pith), or from a single cambial ring. The secondary phloem stratified into hard (fibrous) and soft (parenchymatous) zones (commonly), or not stratified. `Included' phloem absent. Xylem with libriform fibres; with vessels. Vessel end-walls simple (commonly), or simple (sometimes with numerous bars), or reticulately perforated. Vessels without vestured pits. Wood storied, or partially storied (VP, VPI), or not storied; parenchyma paratracheal.
Reproductive type, pollination. Hermaphrodite. Entomophilous, or ornithophilous, or cheiropterophilous.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in `inflorescences'; in cymes and in racemes. The terminal inflorescence unit cymose, or racemose. Inflorescences terminal, or axillary; usually dichasial, tending to cincinnial. Flowers very irregular. The floral asymmetry involving the perianth and involving the androecium (K irregular, C sometimes more or less regular). Flowers more or less 5 merous; cyclic; tetracyclic. Hypogynous disk usually present.
Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; gamosepalous; entire, or toothed; campanulate; unequal but not bilabiate, or bilabiate; often open in bud. Corolla 5; 1 whorled; gamopetalous; imbricate, or valvate (rarely); usually campanulate, or funnel-shaped; bilabiate (often, the upper lip with two lobes, the lower with three), or regular (rarely).
Androecium (4-)5. Androecial members adnate (to the corolla tube); markedly unequal; free of one another; 1 - whorled. Androecium nearly always including staminodes, or exclusively of fertile stamens (occasionally all five members are fertile, or the usual posterior staminode is absent). Staminodes 1 (the posterior, adaxial member), or 3. Stamens (2-)4(-5); didynamous; reduced in number relative to the adjacent perianth (usually), or isomerous with the perianth; oppositisepalous. Anthers connivent (usually), or separate from one another; dehiscing via longitudinal slits; bisporangiate, or tetrasporangiate. Endothecium developing fibrous thickenings, or not developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral. Tapetum amoeboid. Pollen grains aperturate (usually), or nonaperturate; 2-12 - aperturate; colpate, or colporate; 2-celled.
Gynoecium 2; syncarpous; synovarious to synstylovarious; superior. Ovary 1 locular, or 2 locular, or 4 locular. Gynoecium median; stylate. Styles 1; attenuate from the ovary; apical. Stigmas 1; 2 - lobed; wet type; papillate; Group III type. Placentation when unilocular parietal; when 2 or 4 locular axile. Ovules in the single cavity when unilocular, 6-100 (to `many'); 6-50 per locule (`many'); ascending; orthotropous, or hemianatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral to persistent. Synergids hooked (large). Hypostase usually present (but weak). Endosperm formation cellular. Endosperm haustoria present; chalazal, or chalazal and micropylar.
Fruit non-fleshy (usually), or fleshy (rarely); dehiscent (usually), or indehiscent (rarely); a capsule (usually), or a berry (rarely). Capsules septicidal, or loculicidal. Seeds non-endospermic; winged (usually), or wingless. Cotyledons 2 (enlarged, foliaceous). Embryo achlorophyllous (4/4); straight.
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Not cyanogenic. Alkaloids present, or absent. Iridoids recorded (very commonly); carbocyclic and seco-compounds. Proanthocyanidins absent. Flavonols present, or absent; when present, quercetin. Ellagic acid absent (8 species, 7 genera). Arbutin absent. Ursolic acid present. Saponins/sapogenins present (rarely), or absent. Aluminium accumulation not found. Sugars transported as oligosaccharides + sucrose. C3. C3 recorded in Catalpa, Chilopsis.
Geography, cytology. Temperate (a few), or sub-tropical and tropical (mainly). Widespread, with Catalpa common to the Old and New Worlds. N = 20 (mostly). Supposed basic chromosome number of family 7.
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren's Superorder Lamiiflorae; Scrophulariales. Cronquist's Subclass Asteridae; Scrophulariales. Takhtajan's Subclass Asteridae; Lamianae; Scrophulariales. Species 650. Genera 110; Adenocalymna, Amphilophium, Amphitecna, Anemopaegma, Argylia, Arrabidaea, Astianthus, Barnettia, Bignonia, Callichlamys, Campsidium, Campsis, Catalpa, Catophractes, Ceratophytum, Chilopsis, Clytostoma, Colea, Crescentia, Cuspidaria, Cybistax, Delostoma, Deplanchea, Digomphia, Dinklageodoxa, Distictella, Distictis, Dolichandra, Dolichandrone, Eccremocarpus, Ekmanianthe, Fernandoa, Fridericia, Gardnerodoxa, Gibsoniothamnus (~ Scrophulariaceae), Glaziova, Godmania, Haplolophium, Haplophragma, Heterophragma, Hieris, Incarvillea, Jacaranda, Kigelia, Lamiodendron, Leucocalantha, Lundia, Macfadyena, Macranthisiphon, Manaosella, Mansoa, Markhamia, Martinella, Melloa, Memora, Millingtonia, Mussatia, Neojobertia, Neosepicaea, Newbouldia, Nyctcalos, Ophiocolea, Oroxylum, Pajanelia, Pandorea, Parabiognonia, Paragonia, Paratecoma, Parmentiera, Pauldopia, Perianthomega, Periarrabidaea, Perichlaena, Phryganocydia, Phyllarthron, Phylloctenium, Piriadacus, Pithecoctenium, Pleionotoma, Podranea, Potamoganos, Pseudocatalpa, Pyrostegia, Radermachera, Rhigozum, Rhodocolea, Roentgenia, Romeroa, Saritaea, Schlegelia (~ Scrophulariaceae), Sparattosperma, Spathicalyx, Spathodea, Sphingiphila, Spirotecoma, Stereospermum, Stizophyllum, Synapsis (~ Scrophulariaceae), Tabebuia, Tanaecium, Tecoma, Tecomanthe, Tecomella, Tourrettia, Tynanthus, Urbanolophium, Xylophragma, Zeyheria.
Economic uses, etc. Important timber from Tabebuia (West Indian boxwood), Catalpa.
Illustrations. bigno496.gif bigno601.gif bigno602.gif bigno673.gif
Additional, to be intercalated. The twiners twining anticlockwise (Tecoma).
