DELTA home

The families of flowering plants

L. Watson and M.J. Dallwitz

Eupomatiaceae Endl.

Habit and leaf form. Trees and shrubs; bearing essential oils; leptocaul. Mesophytic. Leaves alternate; distichous; petiolate; non-sheathing; gland-dotted, or not gland-dotted; aromatic, or without marked odour; simple; epulvinate. Lamina entire; pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins entire. Leaf development not ‘graminaceous’.

Leaf anatomy. The leaf lamina weakly dorsiventral. Stomata present; mainly confined to one surface (abaxial); paracytic. Lamina without secretory cavities. The mesophyll with spherical etherial oil cells, or without etherial oil cells (?). Minor leaf veins without phloem transfer cells (1 genus).

Axial (stem, wood) anatomy. Young stems with solid internodes. Pith heterogeneous (of large, thin-walled cells and scattered stone cells). Nodes penta-lacunar, or multilacunar (with five or more traces). Primary vascular tissues in a cylinder, without separate bundles to comprising a ring of bundles (traversed by relatively broad rays); collateral. Secondary thickening developing from a conventional cambial ring. Primary medullary rays mixed wide and narrow.

The wood diffuse porous. The vessels small; solitary, radially paired, and in radial multiples. The vessel end-walls oblique; scalariform. The vessels without spiral thickening. The axial xylem with fibre tracheids; including septate fibres. The fibres without spiral thickening. The parenchyma apotracheal and paratracheal; wood not storied. Tyloses absent.

Reproductive type, pollination. Plants hermaphrodite. Pollination entomophilous; via beetles.

Inflorescence, floral, fruit and seed morphology. Flowers solitary (usually), or aggregated in ‘inflorescences’ (sometimes 2–3 together); bracteate. Bracts calyptrate (each flower covered initially by one calyptrate bract, which falls entire). Flowers medium-sized; calyptrate; acyclic. The androecium acyclic and the gynoecium acyclic.

Perianth absent.

Androecium 25–100 (i.e. ‘many’). Androecial members maturing centripetally; free of one another; spiralled. Androecium including staminodes. Staminodes 15–50 (‘many’); internal to the fertile stamens (the inner members being sterile); petaloid. Stamens about 5–15 (‘the few outer members’); laminar to petaloid (the outer, fertile members narrow). Anthers basifixed, or adnate; non-versatile; dehiscing by longitudinal valves; extrorse (the thecae abaxial); appendaged (with a prolonged connective). Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate, or linear (occasionally). Pollen grains aperturate; 2 aperturate, or 3 aperturate; sulculate, or zoniaperturate.

Gynoecium 13–68 carpelled; apocarpous; eu-apocarpous to semicarpous (carpels spiralled); partly inferior (sunken in the top-shaped receptacle). Carpel incompletely closed; 2–11 ovuled. Placentation marginal (ventral). Ovules non-arillate; anatropous; bitegmic.

Fruit fleshy; an aggregate. The fruiting carpels coalescing into a secondary syncarp (and sunken). The fruiting carpel indehiscent. Fruit enclosed in the fleshy receptacle. Seeds endospermic. Endosperm ruminate; oily. Embryo well differentiated (very small).

Seedling. Germination phanerocotylar.

Physiology, phytochemistry. Not cyanogenic. Alkaloids absent (2 species). Iridoids not detected. Proanthocyanidins present; cyanidin. Flavonols absent. Ellagic acid absent. Sieve-tube plastids P-type; type I (b).

Geography, cytology. Temperate to tropical. New Guinea and coastal Eastern Australia. 2n = 20.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Magnoliiflorae; Annonales. Cronquist’s Subclass Magnoliidae; Magnoliales. APG 3 core angiosperms; Superorder Magnolianae; Order Magnoliales.

Species 2. Genera 1; only genus, Eupomatia.

Illustrations. • Eupomatia laurina: Hutchinson. • Eupomatia laurina: Bot. Mag. 81 (1855).

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.’.