The families of flowering plants
Habit and leaf form. Herbs. Perennial; rhizomatous (the rhizome slender, branched, scaly, with a solitary leaf and flower arising from each bud). Leaves long petiolate; simple. Lamina dissected; palmatifid (with five major, cuneate segments, these variously lobed and toothed); with radiating, dichotomous venation, cf. Circaeaster; without cross-venules (the venation open). Leaves exstipulate (?).
Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the androecium (from the staminodes).
Inflorescence, floral, fruit and seed morphology. Flowers solitary; axillary (on long scapes); small; regular. Free hypanthium absent. Hypogynous disk absent.
Perianth petaline; 4–7; free.
Androecium 11–21. Androecial members free of the perianth; free of one another. Androecium including staminodes. Staminodes 8–13; external to the fertile stamens (representing the outer members). Stamens 3–6. Anthers dehiscing via longitudinal slits; bilocular; tetrasporangiate.
Gynoecium 4–9 carpelled; apocarpous; eu-apocarpous; superior. Carpel stylate (the style short, persistent, deflexed in the fruit); 1 ovuled. Placentation apical to marginal (ventral, subapical). Ovules pendulous; orthotropous.
Fruit non-fleshy; an aggregate. The fruiting carpel indehiscent; an achene. Seeds endospermic.
Geography, cytology. Holarctic. Temperate. North and West China.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Ranunculiflorae; Ranunculales. Cronquists Subclass Magnoliidae; Ranunculales. APG 3 core angiosperms; peripheral eudicot; Superorder Ranunculanae; Order Ranunculales (as a synonym of Circaeasteraceae).
Species 1. Genera 1; only genus, Kingdonia.
General remarks. In view of the peculiar leaf venation recalling that of Circaeaster (Circaeasteraceae, q.v.), to which Kingdonia seems closely related, it would be interesting to have information on the embryology. As this description stands, it differs very conspicuously from that of Circaeasteraceae (q.v.) in numerous characters involving habit, leaf form, inflorescence, perianth, anroecium and gynoecium.
Illustrations. • Kingdonia uniflora, with Adonis and Callianthemum: yun nan zhi wu zhi (2000).
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’.