Family Corynocarpaceae

Corynocarpaceae Engl.

Habit and leaf form. Trees, or shrubs. Leaves alternate; spiral; leathery; non-sheathing; simple. Lamina entire. Leaves stipulate, or exstipulate. Stipules intrapetiolar; caducous. Lamina margins entire. Leaves without a persistent basal meristem.

Leaf anatomy. Stomata present; paracytic.

Adaxial hypodermis present. Lamina dorsiventral. Minor leaf veins without phloem transfer cells.

Stem anatomy. Cork cambium present; initially superficial. Secondary thickening developing from a conventional cambial ring. Xylem with libriform fibres. Vessel end-walls horizontal; simple. Wood partially storied (VP); parenchyma probably apotracheal.

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in panicles and in racemes. The ultimate inflorescence unit racemose. Inflorescences terminal. Flowers regular; 5 merous; cyclic; pentacyclic. Free hypanthium present (short, the petals ‘fused to the base of the sepals’). Hypogynous disk present; of separate members (these 5).

Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous; regular; much imbricate. Corolla 5; 1 whorled; polypetalous; imbricate; regular.

Androecium 10. Androecial members adnate (to the base of the corolla); free of one another. Androecium including staminodes. Staminodes 5; external to the fertile stamens, or in the same series as the fertile stamens; petaloid (alternating with the fertile members). Stamens 5; isomerous with the perianth; alternisepalous; opposite the corolla members. Anthers dehiscing via longitudinal slits. Pollen grains aperturate; 2 aperturate; colporate.

Gynoecium 2 carpelled. The pistil 1–2 celled. Gynoecium syncarpous (but one carpel more or less reduced, so that the ovary becomes pseudomonomerous); synovarious; superior. Ovary 1 locular, or 2 locular. Gynoecium stylate. Styles 1, or 2; (when two) free; apical. Placentation when unilocular, apical; when bilocular, apical. Ovules in the single cavity when unilocular, 1; when bilocular, 1 per locule; pendulous; non-arillate; anatropous; bitegmic; crassinucellate. Outer integument not contributing to the micropyle. Polar nuclei fusing prior to fertilization. Antipodal cells formed; proliferating (with up to 8 cells). Endosperm formation nuclear. Embryogeny probably caryophyllad.

Fruit fleshy; indehiscent; a drupe. The drupes with one stone. Fruit 1 seeded. Seeds non-endospermic. Embryo well differentiated. Cotyledons 2 (large, thickened). Embryo straight.

Seedling. Germination phanerocotylar.

Physiology, biochemistry. Not cyanogenic. Proanthocyanidins absent. Flavonols present; kaempferol. Ellagic acid present. Saponins/sapogenins absent.

Geography, cytology. Sub-tropical to tropical. Malaysia, Northern Australia, North Island New Zealand. 2n = 44.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Santaliflorae; Celastrales (?). Cronquist’s Subclass Rosidae; Celastrales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Cucurbitales.

Species 5. Genera 1; only genus, Corynocarpus.