Family Strasburgeriaceae

Strasburgeriaceae Van Tiegh.

~ Ochnaceae

Excluding Ixerbaceae

Habit and leaf form. Trees. Leaves large; alternate; petiolate; non-sheathing; simple. Lamina entire; obovate (-spathulate); pinnately veined; cross-venulate; attenuate at the base. Leaves stipulate. Stipules intrapetiolar; concrescent (the two together forming a short, subentire to bifid scale). Lamina margins remotely dentate.

Leaf anatomy. Stomata present; anomocytic.

Adaxial hypodermis present (mucilaginous). The mesophyll containing mucilage cells (in addition to the hypodermis).

Stem anatomy. Secretory cavities present (in the cortex and pith); with mucilage. Cortical bundles present (? — implied by Metcalfe and Chalk). Internal phloem absent. Secondary thickening developing from a conventional cambial ring. Xylem with tracheids. Vessel end-walls scalariform, or scalariform and simple (?).

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers solitary; axillary (short-pedicellate); regular; partially acyclic. The perianth acyclic (the calyx spirally arranged). Free hypanthium absent. Hypogynous disk present; extrastaminal; annular (thick, sinuous, 10-lobed).

Perianth with distinct calyx and corolla; 13–15; consisting of spiralled calyx and whorled corolla. Calyx 8–10; spiralled; polysepalous (the leathery sepals increasing in size acropetally); persistent (below the fruit); closely imbricate. Corolla 5; 1 whorled; polypetalous; imbricate; rather fleshy. Petals sessile.

Androecium 10. Androecial members free of the perianth; all equal; free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens 10; diplostemonous; both alternating with and opposite the corolla members; filantherous (the filaments stout, subulate). Anthers dorsifixed (oblong, subsagittate); versatile; dehiscing via longitudinal slits (?); introrse. Pollen grains aperturate; 3(–4) aperturate; colporate.

Gynoecium 5 carpelled. Carpels isomerous with the perianth. The pistil 5 celled. Gynoecium syncarpous; eu-syncarpous; superior. Ovary 5 locular (ten ribbed); sessile. Gynoecium stylate. Styles 1; attenuate from the ovary; apical (subulate); about as long as the ovary to much longer than the ovary. Stigmas 1; small, capitate. Placentation axile. Ovules 2 per locule; pendulous; superposed; embryology not recorded.

Fruit fleshy to non-fleshy; globose, indehiscent; capsular-indehiscent, or a berry (‘baccate’, corky-woody when dry, 5–6 cm across). Seeds endospermic (the endosperm fleshy); trigonous, with a broad, winglike, opaque hilum. Embryo well differentiated. Cotyledons 2 (subelliptic). Embryo axile.

Physiology, biochemistry. Aluminium accumulation not found.

Geography, cytology. Paleotropical. Tropical. New Caledonia.

Taxonomy. Subclass Dicotyledonae; Crassinucelli (?). Dahlgren’s Superorder Theiflorae (?); Theales (?). Cronquist’s Subclass Dilleniidae; Theales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Crossosomatales.

Species 1. Genera 1; only genus, Strasburgeria.