| # The families of flowering plants |

L. Watson and M.J. Dallwitz

### Implicit attributes

Unless indicated otherwise, the following attributes are implicit throughout the descriptions, except where the characters concerned are inapplicable.

Habit and leaf form. Non-laticiferous, without coloured juice. ‘Normal’ plants. Leaves well developed. Plants with roots; non-succulent; autotrophic; green and photosynthesizing. Without conspicuous aggregations of leaves. Young stems not breaking easily at the nodes. Rhizome and root tissues not red-pigmented. Self supporting. Stem growth not conspicuously sympodial. Non-marine. Leaves not connate. Leaf sheaths with free margins. Leaves not gland-dotted; without marked odour; with blades ‘normally orientated’; not peltate; epulvinate. Lamina neither inverted nor twisted through 90 degrees; not conspicuously asymmetric. Leaves eligulate. Stipules not ochreate; without colleters. Axillary scales absent. Vernation not circinnate. Leaves becoming compound from primordial lobes. Domatia never explicitly mentioned for the family.

General anatomy. Plants without laticifers. Plants without ‘crystal sand’. Plants without silica bodies.

Leaf anatomy. The leaf lamina without epidermal salt glands. Leaves without ‘pearl glands’. Epidermis without differentiation into ‘long’ and ‘short’ cells; without silica bodies. Stomata present. Guard-cells not ‘grass type’. Urticating hairs absent. Lamina without secretory cavities. Cystoliths absent. The mesophyll without etherial oil cells; not containing mucilage cells; without sclerenchymatous idioblasts.

Axial (stem, wood) anatomy. The cortex without cristarque cells. Pith without diaphragms. Nodes without split-lateral traces. Internal phloem absent. Cortical bundles absent. Medullary bundles absent. The axial xylem with vessels.

The axial xylem without tracheids; without vasicentric tracheids; without fibre tracheids; without libriform fibres; without septate fibres. The secondary phloem not stratified. Tile cells absent.

Root anatomy. Roots without velamen.

Inflorescence, floral, fruit and seed morphology. The fruiting inflorescences not conelike. Flowers not in ‘spikelets’. Inflorescences not scapiflorous; without involucral bracts; not pseudanthial; espatheate. Bracts not calyptrate. Flowers not calyptrate; not resupinate; not exhibiting the androecium internal to the gynoecium; neither papilionaceous nor pseudo-papilionaceous; cyclic. Floral receptacle with neither androphore nor gynophore.

Perianth without spots. Calyx not represented by bristles; neither appendaged nor spurred; not calyptrate. Epicalyx absent. Corolla alternating with the calyx; not appendiculate. Corolla tube not noticeably adaxially split. Corolla not calyptrate; not spurred; not fleshy.

Androecial members unbranched; free of the gynoecium. Androecium exclusively of fertile stamens. Staminodes non-petaloid. Stamens not didynamous, not tetradynamous; filantherous. Filaments not appendiculate. Anthers separate from one another; not becoming inverted during development; bilocular; unappendaged. Pollen shed as single grains. Pollen grains not dispersed as long filaments. The ulcus without an operculum; without an annulus.

Gynoecium non-petaloid. Carpel fully closed. Styles free. Locules without ‘false septa’; not horizontally divided. Styles without an indusium. Stigmas dorsal to the carpels.

Fruit not an aggregate. The fruiting carpels not coalescing. Fruit without fleshy investment external to the original ovary. Gynoecia of adjoining flowers not forming a multiple fruit. The multiple fruits not coalescing. Endosperm not ruminate. Perisperm absent. Seeds not conspicuously hairy; with a testa; wingless; without amyloid. Embryo well differentiated. Testa without phytomelan. Micropyle not zigzag.

Seedling. Seed germination not 'orchidaceous'. Coleoptile absent. Primary root persistent. Nitrogen-fixing root nodules absent.

Physiology, phytochemistry. Inulin not found. Mustard-oils absent. Polyacetylenes not found. Berberine absent. Betalains absent. Andromedotoxin not recorded.

Special distinguishing feature. Gynoecium and fruit not open as in typical Resedaceae. Lamina tip not abaxially pouched (i.e., not as in Saccifoliaceae). Epicalyx not double and complex as in Triplostegiaceae.

Geography, cytology. Chromosomes with normal centromeres.

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: 8th June 2026. delta-intkey.com’.

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