The families of flowering plants
Habit and leaf form. Small, Olea-like trees; non-laticiferous. Leaves opposite; simple. Lamina entire; lanceolate; pinnately veined. Leaves exstipulate. Lamina margins entire.
Leaf anatomy. Stomata mainly laterocytic. Cystoliths absent.
Axial (stem, wood) anatomy. Nodes unilacunar (with one trace). Internal phloem absent. Secondary thickening developing from a conventional cambial ring. Primary medullary rays mixed wide and narrow.
The vessel end-walls horizontal; simple. The vessels without vestured pits. The axial xylem without tracheids; with libriform fibres. Included phloem absent.
Reproductive type, pollination. Plants dioecious. Pollination anemophilous.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences; in cymes. The ultimate inflorescence units cymose. Inflorescences axillary. Flowers ebracteate; ebracteolate; small; regular. Free hypanthium absent.
Perianth sepaline; 3, or 4; 1 whorled. Calyx 3, or 4 (the sepals of the female flowers pinnately net-veined); 1 whorled; gamosepalous (at the base). Calyx lobes markedly longer than the tube. Calyx regular; persistent; in the female flowers, slightly accrescent; of male flowers, valvate.
Androecium 6–9(–12). Androecial members free of the perianth; free of one another. Androecium exclusively of fertile stamens. Stamens 6–9(–12); diplostemonous to triplostemonous; erect in bud; filantherous (with very short filaments). Anthers basifixed; dehiscing via longitudinal slits; elongate, the connective apiculate. Pollen grains aperturate; 3 aperturate; colporate (colporoidate).
Gynoecium 1–3 carpelled. Carpels reduced in number relative to the perianth to isomerous with the perianth. The pistil 1 celled (when monomerous, i.e. usually), or 2–3 celled (when semicarpous). Gynoecium monomerous (usually), or apocarpous, or syncarpous; of one carpel (usually), or eu-apocarpous, or semicarpous (the carpels sometimes joined basally); superior. Carpel long stylate; apically stigmatic (the stigma decurrent on the long style); 1 ovuled. Placentation apical. Ovary 2 locular, or 3 locular. Styles free; apical. Placentation when semicarpous, apical. Ovules 1 per locule; pendulous; anatropous; apparently unitegmic.
Fruit non-fleshy; an aggregate (when G 2 or 3), or not an aggregate (when monomerous). The fruiting carpel when apocarpous or monomeric, indehiscent; nucular (shortly beaked). Fruit when semicarpous, of 23 basally joined nucules(?). Seeds non-endospermic. Embryo well differentiated. Cotyledons 2. Embryo straight.
Physiology, phytochemistry. Ellagic acid present.
Geography, cytology. Paleotropical. Sub-tropical. North East Africa, Arabia.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Malviflorae; Urticales. Cronquists Subclass Hamamelidae; Urticales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Rosales.
Species 1. Genera 1; Barbeya oleoides the only representative.
Illustrations. • Barbeya oleoides (Hutchinson).
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: 9th January 2018. delta-intkey.com/angio’.