The Families of Flowering Plants

L. Watson and M. J. Dallwitz


Ebenaceae Gurke

Including Diospyraceae Van Tiegh., Guaiacanae (Guaiacanaceae) Juss., Styraceae (Styracaceae) Spreng. (p.p.)

Habit and leaf form. Trees, or shrubs (or rarely ‘subshrubs’). Mesophytic. Leaves alternate (usually), or opposite, or whorled; usually spiral; leathery; petiolate; non-sheathing; simple. Lamina entire; pinnately veined; cross-venulate. Leaves exstipulate.

Leaf anatomy. Lamina dorsiventral (usually), or isobilateral; without secretory cavities. The mesophyll with sclerencymatous idioblasts (especially in Diospyros), or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Diospyros).

Stem anatomy. Cork cambium present; initially deep-seated, or superficial. Nodes unilacunar, or tri-lacunar. Secondary thickening developing from a conventional cambial ring. Xylem with fibre tracheids; with vessels. Vessel end-walls simple. Vessels without vestured pits. Primary medullary rays narrow. Wood storied (some Diospyros), or partially storied (?), or not storied (?); parenchyma apotracheal.

Reproductive type, pollination. Plants dioecious (mostly), or hermaphrodite (rarely). Female flowers with staminodes, or without staminodes (less often). Gynoecium of male flowers pistillodial, or vestigial, or absent.

Inflorescence, floral, fruit and seed morphology. Flowers solitary (especially when female), or aggregated in ‘inflorescences’; in cymes. The terminal inflorescence unit cymose. Inflorescences axillary; small cymes. Flowers bracteolate; small; regular; (2–)3–5(–7) merous; cyclic; tetracyclic, or pentacyclic. Free hypanthium absent.

Perianth with distinct calyx and corolla; 6–14; 2 whorled; isomerous. Calyx 3–7; 1 whorled; gamosepalous; blunt-lobed; regular; persistent; often accrescent (around the fruit), or non-accrescent; imbricate, or valvate. Corolla 3–7; 1 whorled; gamopetalous; lobes contorted; tubular, or campanulate, or urceolate, or vase-shaped; regular; white, or yellow (or cream), or pink.

Androecium 3–28 (or more?). Androecial members branched, or unbranched; free of the perianth, or adnate (epipetalous at the base of the tube), or free of the perianth and adnate; free of one another, or coherent (often paired, by branching); 1 whorled, or 2 whorled, or 3 whorled, or 4 whorled. Androecium exclusively of fertile stamens, or including staminodes. Stamens 3–28 (or more?); inserted when epipetalous, near the base of the corolla tube; reduced in number relative to the adjacent perianth to isomerous with the perianth (rarely), or diplostemonous to polystemonous (one to four times the number of C lobes); oppositisepalous. Anthers dehiscing via pores (apical), or dehiscing via longitudinal slits; introrse; tetrasporangiate. Endothecium not developing fibrous thickenings (in Diospyros kali). Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with more than one middle layer. Pollen grains aperturate; 3 aperturate; colporate; 2-celled.

Gynoecium 2–5(–16) carpelled. The pistil 4–30 celled. Gynoecium syncarpous; synovarious to synstylovarious; superior (Lissocarpa being referred to a separate family). Ovary 2–5(–16) locular (each locule partially divided by a false septum). Locules partially secondarily divided by ‘false septa’. Styles 2–5(–8); free, or partially joined; apical. Stigmas 2–8; 1–2 lobed; dry type; non-papillate; Group II type. Placentation apical. Ovules 2 per locule (the false septa separating the members of each pair); pendulous; apotropous; with dorsal raphe; non-arillate; anatropous; bitegmic; tenuinucellate. Outer integument not contributing to the micropyle. Endothelium differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization (?), or not fusing. Antipodal cells formed; 3; not proliferating; ephemeral. Endosperm formation nuclear.

Fruit fleshy (usually), or non-fleshy (occasionally leathery); indehiscent (usually), or dehiscent (rarely tardily so); a berry, or a drupe, or a capsule (rarely). Capsules valvular. Seeds endospermic. Endosperm ruminate, or not ruminate; oily. Seeds large. Cotyledons 2. Embryo achlorophyllous (1/3); straight, or curved.

Seedling. Germination phanerocotylar, or cryptocotylar.

Physiology, biochemistry. Cyanogenic (?), or not cyanogenic. Alkaloids present (rarely), or absent. Iridoids not detected. Proanthocyanidins present, or absent; delphinidin, or cyanidin and delphinidin. Flavonols present; kaempferol, or kaempferol and quercetin, or kaempferol, quercetin, and myricetin. Ellagic acid present, or absent (variable in Diospyros). Arbutin absent. Saponins/sapogenins present. Aluminium accumulation not found. Sugars transported as sucrose, or as sugar alcohols + oligosaccharides + sucrose (in different species of Diospyros). C3 (?), or CAM. CAM recorded directly in Maba (non-succulent, and dubious).

Geography, cytology. Temperate (a few), or sub-tropical to tropical (mainly). Pantropical, especially Indomalayan, with a few temperate outliers. X = 15.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Primuliflorae; Ebenales. Cronquist’s Subclass Dilleniidae; Ebenales. APG (1998) Eudicot; core Eudicot; Asterid; unassigned to Euasterid I or Euasterid II; Ericales. Species 500. Genera 2; Diospyros, Euclea.

Economic uses, etc. Important sources of timber (ebony) and fruits (mabolo, persimmon).

Illustrations. • Technical details (Diospyros). • Technical details (Diospyros). • Technical details (Diospyros).

Quotations

Is ebony like her? O wood divine!
(‘Love’s Labour’s Lost’, iv., 3)


Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).

Index