The families of flowering plants
Excluding Behniaceae, Ripogonaceae.
Habit and leaf form. Scandent shrubs and herbs, or lianas. Normal plants. Perennial; without conspicuous aggregations of leaves; rhizomatous, or tuberous. Climbing; tendril climbers (the tendrils from the petiole bases), or petiole twiners (the tendrils sometimes reduced to points). Mesophytic and xerophytic. Leaves evergreen; alternate (mostly), or opposite; usually leathery; petiolate to subsessile; sheathing (rarely), or non-sheathing. Leaf sheaths when present, with free margins. Leaves foetid, or without marked odour; simple (though the tendrils, sometimes called stipules, have also been interpreted as representing the midveins of lateral leaflets). Lamina entire; lanceolate, or ovate; one-veined, or palmately veined (curved-convergent); cross-venulate; cordate, or hastate, or attenuate at the base. Leaves stipulate (ostensibly, if the tendril bases be so interpreted), or exstipulate. Lamina margins entire.
Leaf anatomy. The leaf lamina dorsiventral. Stomata present; anomocytic. Hairs present, or absent. Foliar vessels present, or absent; with scalariform end-walls. Minor leaf veins without phloem transfer cells (Smilax).
Axial (stem, wood) anatomy. Secretory cavities present. Cork cambium present. Secondary thickening absent.
The vessel end-walls scalariform.
Root anatomy. Root xylem with vessels; vessel end-walls scalariform.
Reproductive type, pollination. Plants dioecious. Pollination entomophilous.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in inflorescences; when aggregated, in cymes, or in racemes, or in spikes, or in umbels, or in verticils. Inflorescences not scapiflorous; terminal, or axillary; often of one or more superimposed verticils appearing as racemes, spikes or umbels. Flowers regular; 3 merous; cyclic. Perigone tube present (short or long), or absent.
Perianth of tepals; 6; free, or joined; 2 whorled; isomerous; petaloid (but fairly inconspicuous); similar in the two whorls to different in the two whorls (the inner members more or less reduced, sometimes fringed).
Androecium 3 (rarely), or 6 (usually), or 9–18 (rarely). Androecial members free of the perianth; free of one another, or coherent; sometimes 1 adelphous (the filaments then fused into a tube or column); (1–)2(–6) whorled. Androecium exclusively of fertile stamens. Stamens 6 (usually), or 3, or 9, or 12, or 15, or 18; isomerous with the perianth to polystemonous; filantherous. Anthers basifixed; dehiscing via longitudinal slits; introrse, or latrorse; unilocular; tetrasporangiate. The endothecial thickenings spiral. Microsporogenesis successive. The initial microspore tetrads isobilateral. Tapetum glandular. Pollen shed as single grains. Pollen grains nonaperturate (or indistinctly so); 2-celled.
Gynoecium 1 carpelled (rarely), or 3 carpelled. Carpels isomerous with the perianth, or reduced in number relative to the perianth (rarely). The pistil 1 celled, or 3 celled. Gynoecium monomerous (rarely), or syncarpous; of one carpel (rarely), or synovarious to synstylovarious; superior. Carpel stylate; apically stigmatic; when monocarpellary 1 ovuled, or 2 ovuled. Ovary when syncarpous 3 locular. Gynoecium stylate, or non-stylate to stylate. Styles 3; free (usually), or partially joined; apical. Stigmas dry type; papillate; Group II type. Placentation axile. Ovules 1 per locule, or 2 per locule; pendulous; non-arillate; orthotropous (usually), or hemianatropous, or campylotropous; bitegmic; crassinucellate. Embryo-sac development Polygonum-type. Endosperm formation nuclear.
Fruit fleshy. The fruiting carpel when monocarpellary, baccate. Fruit when syncarpous (i.e. usually) indehiscent; a berry; usually 3 seeded. Seeds endospermic. Endosperm oily. Embryo well differentiated (mostly small). Embryo straight. Testa without phytomelan.
Seedling. Hypocotyl internode present (not elongated, but a long epicotyl present). Seedling collar not conspicuous. Cotyledon hyperphyll compact; non-assimilatory. Coleoptile absent. Seedling cataphylls present. First leaf dorsiventral. Primary root persistent.
Physiology, phytochemistry. C3. C3 physiology recorded directly in Smilax. Anatomy non-C4 type (Smilax). Saponins/sapogenins present. Proanthocyanidins absent. Flavonols present, or absent; when present, quercetin, or kaempferol and quercetin. Ellagic acid absent.
Geography, cytology. Holarctic, Paleotropical, Neotropical, Cape, and Australian. Temperate (warm), sub-tropical to tropical. Widespread, tropical, subtropical and warm temperate. X = 10, 13–16.
Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Liliiflorae; Dioscoreales. APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Liliales.
Species 370. Genera 3; Heterosmilax, Pseudosmilax, Smilax.
Illustrations. • Technical details: Smilax (Lindley). • Technical details: Smilax.
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: 12th September 2017. delta-intkey.com/angio’.