The families of flowering plants
Habit and leaf form. Shrubs, or lianas, or herbs; laticiferous, or non-laticiferous. Normal plants. Perennial; with a basal aggregation of leaves, or without conspicuous aggregations of leaves. Self supporting, or epiphytic (rarely), or climbing; when climbing, root climbers (with short, climbing roots, sometimes also with long, unbranched rope roots). Leaves alternate; spiral (usually), or distichous; herbaceous, or leathery; petiolate; sheathing; simple, or compound; when compound palmate, or bifoliolate (Cyclanthus). Lamina when simple dissected (usually), or entire; when dissected, palmatifid (or bifid, in Cyclanthus); one-veined, or palmately veined (with one to three costae, the central lacking in Cyclanthus). Leaf development not graminaceous.
General anatomy. Plants without silica bodies.
Leaf anatomy. Stomata present; tetracytic. Lamina with secretory cavities, or without secretory cavities (Cyclanthus). Secretory cavities containing mucilage (Carludovicoideae). The mesophyll containing crystals. The crystals raphides, or druses, or solitary-prismatic (including styloids). Foliar vessels present, or absent (then with vessel tracheids); with scalariform end-walls.
Axial (stem, wood) anatomy. Secretory cavities present (usually), or absent (Cyclanthus, which has latex canals confined to the infloresence); when present, with mucilage. Cork cambium present (usually), or absent (Cyclanthus). Secondary thickening absent. The axial xylem without vessels (Wagner 1977).
Root anatomy. Root xylem with vessels, or without vessels (then with vessel tracheids); vessel end-walls scalariform.
Reproductive type, pollination. Fertile flowers functionally male, or functionally female. Plants monoecious. Female flowers with staminodes (with four conspicuous staminodia opposite the tepals, these subulate, vermiform or filiform, (1-)3–5(-10) cm long, white to red or yellow, with or without rudimentary anthers). Gynoecium of male flowers absent. Floral nectaries absent (nectaries absent). Pollination entomophilous; via beetles.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences. Inflorescences terminal, or axillary; pedunculate, unbranched, long-cylindrical to subspherical spadices, with rather few to very numerous flowers; conspicuously spatheate (each spadix subtended by 24(-8) spathes, which vary in size, shape and colour green, white, red or yellow). Flowers small (in most genera arranged in a chess-board mosaic of solitary females each surrounded by four males, the groups in a shallow spiral along the spadix; or in Cyclanthus, the male and female flowers in alternating cycles and fused laterally so as to be indistinguishable individually).
Perianth of tepals, or vestigial, or absent; 4; free, or joined (symmetric or asymmetric, usually a more or less lobed cupule when present in male flowers, free or basally connate in females); 1 whorled (usually), or 2 whorled (seemingly, in Evodianthus); sepaloid; fleshy (often, in female flowers), or non-fleshy; persistent; accrescent (often, in female flowers).
Androecium 4 (in female flowers), or 10–20(–150) (in male flowers of most genera, but in Cyclanthus the male flowers are so reduced as to be represented by cycles with numerous stamens in four rows). Androecial members free of the perianth; free of one another. Stamens 10–20(–150) (when individual flowers distinguishable); triplostemonous to polystemonous; often with basally bulbous filaments. Anthers basifixed; non-versatile; tetrasporangiate; appendaged, or unappendaged. The anther appendages when present, apical (in the form of a glandule). Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis successive. The initial microspore tetrads isobilateral, or decussate. Pollen grains aperturate; 1 aperturate (usually), or 2 aperturate; sulcate (or sulcoidate, mostly), or ulcerate (or ulceroidate, and Carludovicia having a proximal pore and a distal groove), or foraminate (biforaminate, Thoracocarpus); 2-celled.
Gynoecium 4 carpelled. Carpels isomerous with the perianth. The pistil 1 celled. Gynoecium syncarpous; synovarious to synstylovarious; partly inferior, or inferior. Ovary 1 locular (or in Cyclanthus, the female flowers reduced and fused into pistillate cycles, to the extent that the ovaries form a continuous cavity). Epigynous disk absent. Gynoecium non-stylate, or stylate. Styles 1, or 4; free to partially joined. Stigmas 4; laterally compressed, or flat, broad and fleshy; wet type; papillate; Group III type. Placentation parietal (with four placentas, or numerous parietal ovules in the continous cavity of Cyclanthus), or apical (rarely). Ovules in the single cavity 50–150 (many); anatropous; tenuinucellate, or crassinucellate to pseudocrassinucellate (mostly). Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed, or not formed (? contrast Davis 1966, pp. 21, 102); if formed, 3; not proliferating; ephemeral, or persistent. Synergids pear-shaped. Endosperm formation helobial.
Fruit fleshy; indehiscent; a berry (these usually more or less cohering within the spadix, sometimes coming free). Gynoecia of adjoining flowers usually combining to form a multiple fruit. The multiple fruits usually coalescing (to form a fleshy syncarp, the spadix twisting and becoming screwlike in Cyclanthus). Seeds copiously endospermic. Endosperm oily, or not oily (?). Seeds winged (with a long terminal appendage, in Stelestylis), or wingless. Seeds with starch (Cyclanthoideae), or without starch (Carludovicioideae). Embryo well differentiated (small to medium sized). Cotyledons 1. Embryo straight (usually, linear-cylindric), or curved (rarely). Testa without phytomelan.
Seedling. Hypocotyl internode absent. Seedling collar not conspicuous. Cotyledon hyperphyll compact; non-assimilatory. Coleoptile absent (but with pronounced cotyledon sheath lobes). First leaf dorsiventral. Primary root ephemeral.
Physiology, phytochemistry. Accumulated starch exclusively pteridophyte type (Cyclanthoideae), or other than exclusively pteridophyte type (Carludovicioideae). Not cyanogenic. Alkaloids present (one species). Proanthocyanidins absent. Flavonols absent. Ellagic acid absent. Sieve-tube plastids P-type; type II.
Geography, cytology. Neotropical. Sub-tropical to tropical. Central and tropical South America, West Indies.
Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Cyclanthiflorae; Cyclanthales. APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Pandanales.
Species 180. Genera 12; Asplundia, Carludovica, Chorigyne, Cyclanthus, Dianthoveus, Dicranopygium, Evodianthus, Ludovia, Schultesiophytum, Sphaeradenia, Stelestylis, Thoracocarpus.
Economic uses, etc. Carludovica leaves are made into Panama hats.
Illustrations. • Technical details: Carludovica. • Carludovica, Cyclanthus (inflorescences).
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: 19th October 2016. delta-intkey.com’.