| | The Families of Angiosperms |
Habit and leaf form. Trees, or ‘arborescent’ (being occasionally palm-like), or shrubs, or lianas (mostly twining shrubs). Self supporting, or climbing (mostly); mostly stem twiners. Leaves alternate; spiral; leathery; petiolate; non-sheathing; not gland-dotted; compound; unifoliolate, or ternate, or pinnate; when pinnate, imparipinnate; exstipulate; leaf development not ‘graminaceous’.
Leaf anatomy. The leaf lamina dorsiventral. Mucilaginous epidermis present, or absent. Stomata mainly confined to one surface (abaxial); paracytic (commonly), or cyclocytic, or diacytic (rarely). Hairs of numerous kinds present (in the family, variously unicellular with one or two arms, sympodially branched, or tufted); mostly eglandular (with glandular forms mostly confined to floral parts). Adaxial hypodermis present, or absent. Lamina with secretory cavities, or without secretory cavities. Secretory cavities when present, containing mucilage, or containing resin. The mesophyll containing crystals, or without crystals. The crystals where recorded, solitary-prismatic.
Axial (stem, wood) anatomy. Secretory cavities present, or absent; with mucilage. Cork cambium present; initially superficial. Nodes tri-lacunar to multilacunar. Primary vascular tissues in a cylinder, without separate bundles; collateral. Internal phloem absent. Cortical bundles absent. Medullary bundles absent. Secondary thickening developing from a conventional cambial ring (usually), or anomalous. The anomalous secondary thickening when present, via concentric cambia (Rourea). Primary medullary rays narrow.
The wood semi-ring porous, or diffuse porous. The vessels medium, or large; in various combinations of solitary, radially paired, in radial multiples, and clustered. The vessel end-walls simple. The axial xylem with tracheids, or without tracheids (?); commonly with vasicentric tracheids; without fibre tracheids; with libriform fibres; at least sometimes including septate fibres, or without septate fibres. The fibres with spiral thickening, or without spiral thickening. The parenchyma scanty paratracheal (typically, or absent). ‘Included’ phloem present (Rourea), or absent. The wood not storied. Tyloses present, or absent.
Reproductive type, pollination. Unisexual flowers present, or absent. Plants hermaphrodite (usually), or dioecious.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in panicles and in racemes. The ultimate inflorescence units cymose, or racemose (?). Inflorescences terminal, or axillary. Flowers small; regular, or somewhat irregular; 5 merous. Free hypanthium absent. Hypogynous disk present (small), or absent.
Perianth with distinct calyx and corolla; (8–)10; 2 whorled; isomerous. Calyx (4–)5; 1 whorled; polysepalous, or gamosepalous; persistent; imbricate, or valvate; with the median member anterior (?). Corolla (4–)5; 1 whorled; polypetalous, or gamopetalous; imbricate (usually), or valvate (rarely); regular.
Androecium 10 (usually), or 5. Androecial members free of the perianth; often markedly unequal (the antesepalous members longer); free of one another, or coherent (below); when coherent 1 adelphous; usually 2 whorled. Androecium exclusively of fertile stamens, or including staminodes. Staminodes when present, 1–5; internal to the fertile stamens, or in the same series as the fertile stamens and internal to the fertile stamens (from the inner whorl). Stamens 5–10; isomerous with the perianth, or diplostemonous. Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 3(–4) aperturate; colpate, or colporate.
Gynoecium 1 carpelled, or 3 carpelled, or 5 carpelled, or 7 carpelled, or 8 carpelled (often 5 with 4 abortive). The pistil when monomerous or semicarpous, 1 celled, or 3 celled, or 5 celled, or 7 celled, or 8 celled. Gynoecium monomerous, or apocarpous; of one carpel, or eu-apocarpous, or semicarpous (carpels sometimes more or less connate basally); superior. Carpel apically stigmatic; 2 ovuled. Placentation marginal to basal (‘marginal’, cf. Leguminosae). Ovules ascending; collateral (but one usually abortive); arillate (often), or non-arillate; orthotropous (always?); 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. Endosperm formation nuclear.
Fruit non-fleshy; an aggregate, or not an aggregate (often a single follicle). The fruiting carpels coalescing into a secondary syncarp to not coalescing. The fruiting carpel dehiscent, or indehiscent; a follicle, or nucular. Seeds endospermic, or non-endospermic. Endosperm when present, oily.
Seedling. Germination cryptocotylar.
Physiology, phytochemistry. Alkaloids absent (one species). Saponins/sapogenins absent. Proanthocyanidins present; cyanidin and delphinidin. Flavonols present; kaempferol, quercetin, and myricetin. Ellagic acid absent (Connarus).
Geography, cytology. Tropical. Pantropical. X = 13 or 14.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Rutiflorae; Rutales, or Sapindales (?). Cronquist’s Subclass Rosidae; Rosales. APG III core angiosperms; core eudicot; Superorder Rosanae; fabid. APG IV Order Oxalidales.
Species 300–350. Genera about 18; Agelaea, Burttia, Cnestidium, Cnestis, Connarus, Ellipanthus, Hemandradenia, Jollydora, Manotes, Pseudoconnarus, Rourea, Roureopsis, Taeniochlaena, Vismianthus.
General remarks. RbcL sequencing (Chase et al, 1993) was in accord with comparative morphology, etc., in requiring removal of Connaraceae from Sapindales/Rutales.
Illustrations. • Connarus smeathmannii: Thonner. • Connarus pinnatus: Lindley. • Connarus pinnatus: R. Wight (1840). • Ellipanthus madagascariensis and Rourea orientalis: Humbert, Flore de Madagascar et Comores 97 (1958). • Roureopsis griffithii, as Taeniochlaena: Hook. Ic. Pl. 24 (1895). • Leaf hairs: Connarus (Solereder, 1908).
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: 25th April 2024. delta-intkey.com’.
