The families of flowering plants
Habit and leaf form. Herbs, or lianas (at least, some sublianoid). With a basal aggregation of leaves, or without conspicuous aggregations of leaves; rhizomatous (with sympodial rhizomes). Self supporting, or epiphytic, or climbing (occasionally). Mesophytic. Leaves alternate; distichous, or spiral to distichous; petiolate (the petioles often long, sometimes winged); sheathing. Leaf sheaths with free margins. Leaves simple (often colour-patterned); pulvinate (between blade and petiole). Lamina entire; conspicuously asymmetric (with the inner half-lamina larger); lanceolate, or oblong, or ovate; pinnately veined (or pinnate-parallel); without cross-venules; attenuate at the base, or cuneate at the base, or oblique at the base, or rounded at the base. Leaves eligulate. Lamina margins entire. Vernation convolute.
General anatomy. Plants with silica bodies (these hat-shaped or as druses).
Leaf anatomy. Epidermis without silica bodies. Stomata present; paracytic, or tetracytic. The mesophyll not containing mucilage cells; containing crystals. The crystals druses, or solitary-prismatic (no raphides). Foliar vessels absent. Minor leaf veins without phloem transfer cells (Marantochloa).
Axial (stem, wood) anatomy. Secondary thickening absent.
The vessel end-walls simple (mainly), or scalariform and simple.
Root anatomy. Root xylem with vessels; vessel end-walls scalariform, or simple.
Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the gynoecium (via septal nectaries at the summit of the ovary). Pollination entomophilous; mechanism conspicuously specialized (usually with an explosive pollination mechanism, with the style held under tension by the labellum until the latter is moved).
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences (paired, the pairs aggregated or not); in cymes. The ultimate inflorescence units cymose. Inflorescences scapiflorous, or not scapiflorous; terminal, or axillary; consisting of monochasial cymes or thyrses; pseudanthial (in the sense that in each pair, each asymmetric flower complements the other in mirror-image). Flowers bracteate (each pair subtended by a bract); bracteolate, or ebracteolate; very irregular; asymmetric. The floral irregularity involving the perianth and involving the androecium. Flowers cyclic; tetracyclic, or pentacyclic. Perigone tube present, or absent (the sepals free, the petals more or less joined into a long or short tube).
Perianth with distinct calyx and corolla; 6; free and joined (sepals free, petals joined); 2 whorled; isomerous; different in the two whorls. Calyx 3; 1 whorled; polysepalous. Corolla 3; 1 whorled; gamopetalous (with a basal tube); unequal but not bilabiate (one petal often hoodlike and larger); white, or pink.
Androecium (3–)4–5. Androecial members adnate (to the corolla tube); free of the gynoecium (but one of the inner staminodes forming a labellum over the pistil, the other often a landing stage for insects); coherent (the members of the outer whorl forming a tube longer than the petals, with which they are fused basally); 2 whorled. Androecium including staminodes (only the posterior member of the inner whorl is fertile, this bearing a fertile half-anther and a larger or smaller petaloid staminodal appendage). Staminodes (2–)3, or 4 (petaloid but small, two from the inner whorl, other (1-)2 the lateral(s) of the outer whorl, the median outer member always absent); external to the fertile stamens and in the same series as the fertile stamens; petaloid. Stamens 1; reduced in number relative to the adjacent perianth; petaloid. Anthers adnate (the single fertile stamen with a pollen sac on one edge); non-versatile; dehiscing via longitudinal slits; introrse; unilocular. The endothecial thickenings spiral. Microsporogenesis successive. Pollen grains nonaperturate (without an exine); 2-celled (Maranta).
Gynoecium 3 carpelled. The pistil (1–)3 celled. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; inferior. Ovary 3 locular (but two often empty or obsolete). Styles 1; free; apical. Stigmas wet type; non-papillate; Group IV type. Placentation axile to basal. Ovules 1 per locule; arillate (often), or non-arillate; anatropous (to anacampylotropous); bitegmic; crassinucellate. Outer integument contributing to the micropyle, or not contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; proliferating (sometimes in Calathea), or not proliferating; ephemeral, or persistent. Synergids pear-shaped. Endosperm formation nuclear. Embryogeny chenopodiad.
Fruit fleshy, or non-fleshy; dehiscent (usually), or indehiscent; a capsule (usually), or capsular-indehiscent, or a berry. Capsules loculicidal. Seeds endospermic. Perisperm present. Seeds with starch. Embryo achlorophyllous (1/1); curved, or bent. Testa encrusted with phytomelan; black.
Seedling. Hypocotyl internode absent. Mesocotyl present, or absent. Seedling collar conspicuous. Cotyledon hyperphyll compact; non-assimilatory. Coleoptile present. First leaf dorsiventral. Primary root ephemeral.
Physiology, phytochemistry. Accumulated starch other than exclusively pteridophyte type. Not cyanogenic. Proanthocyanidins present, or absent; when present, cyanidin. Flavonols present (Calathea, Thalea), or absent; when present, kaempferol and quercetin. Ellagic acid absent. Sieve-tube plastids P-type; type II.
Geography, cytology. Sub-tropical to tropical. Pantropical and subtropical. X = 4–14 (or more).
Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Zingiberiflorae; Zingiberales. APG 3 core angiosperms; Superorder Lilianae; commelinid Monocot; Order Zingiberales.
Species 400. Genera 30; Afrocalathea, Ataenidia, Calathea, Cominsia, Ctenanthe, Donax, Halopegia, Haumania, Hylaeanthe, Hypselodelphys, Ischnosiphon, Koernickanthe, Maranta, Marantochloa, Megaphrynium, Monophrynium, Monophyllanthe, Monotagma, Myrosma, Phacelophrynium, Phrynium, Pleiostachya, Sanblasia, Saranthe, Sarcophrynium, Schumannianthus, Stachyphrynium, Stromanthe, Thalia, Thaumatococcus, Trachyphrynium.
Illustrations. • Marantochloa purpurea, as Clinogyne arillata: Thonner. • Le Maout and Decaisne: Stromanthe, Thalia. • Le Maout and Decaisne: Calathea, Maranta. • Calathea grandiflora: Bot. Reg. 932, 1825. • Calathea veitchiana: Bot. Mag. 91 (1865).
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: 24th October 2017. delta-intkey.com/angio’.