Family Bruniaceae

Bruniaceae DC.

Including Berzeliaceae Nak.

Habit and leaf form. Ericoid shrubs (usually, or undershrubs), or trees (rarely). Leaves evergreen; small; alternate; spiral (usually in five rows); mostly subtrigonous and acerose; imbricate (usually), or not imbricate; non-sheathing; simple. Lamina entire; parallel-veined (usually three veined, occasionally with 5 or up to twenty veins). Leaves exstipulate (or stipules vestigial).

Leaf anatomy. Stomata present; anomocytic.

Lamina isobilateral to centric (commonly), or dorsiventral (partly or wholly, in a few species).

Stem anatomy. Cork cambium present; initially superficial. Secondary thickening developing from a conventional cambial ring. Xylem with tracheids. Vessel end-walls oblique; scalariform. Wood parenchyma scanty paratracheal.

Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers solitary (occasionally), or aggregated in ‘inflorescences’ (usually); when solitary, terminal, or axillary; when aggregated, in spikes, or in heads. Inflorescences of sessile flowers, in spikes or more often in heads, the latter sometimes in panicles or racemes, occasionally the flowers solitary and terminal or axillary; with involucral bracts, or without involucral bracts; pseudanthial, or not pseudanthial. Flowers usually 5 bracteate; small (mostly), or medium-sized; regular; (4–)5 merous; cyclic; tetracyclic. Free hypanthium present, or absent. Hypogynous disk present, or absent; when present, intrastaminal.

Perianth with distinct calyx and corolla; (8–)10; 2 whorled; isomerous. Calyx (4–)5; 1 whorled; polysepalous, or gamosepalous; when gamosepalous, (4-)5 blunt-lobed; regular; persistent; imbricate. Corolla (4–)5; 1 whorled; polypetalous, or gamopetalous (in Lonchostoma); imbricate; regular; persistent (often), or deciduous. Petals clawed (often), or sessile.

Androecium (4–)5 (often persistent). Androecial members free of the perianth (usually), or adnate (the filaments sometimes adnate to the claws of the petals to form a tube, or in Lonchostoma the anthers subsessile and borne on the corolla tube); all equal; free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens (4–)5; isomerous with the perianth; oppositisepalous; alternating with the corolla members; inflexed in bud; almost with sessile anthers (Lonchostoma), or filantherous. Anthers dorsifixed; versatile (often), or non-versatile; dehiscing via longitudinal slits; introrse; appendaged, or unappendaged. The anther appendages when present, apical (by prolongation of the connective). Pollen shed as single grains. Pollen grains aperturate; 3 aperturate, or 6–11 aperturate; colporate (or colporoidate).

Gynoecium 2 carpelled (usually), or 3 carpelled (Audouinia), or 1 carpelled (seemingly, in Mniothamnea and Berzelia). Carpels reduced in number relative to the perianth. The pistil 1–3 celled. Gynoecium monomerous (or pseudomonomerous?), or syncarpous; of one carpel (Mniothamnea, Berzelia), or synovarious to synstylovarious; partly inferior to inferior (usually), or superior (Raspailia). Carpel when seeming monomerous, stylate; apically stigmatic; 1 ovuled. Placentation apical. Ovary when syncarpous, 2 locular (usually), or 3 locular (Audouinia). Gynoecium stylate. Styles when syncarpous, 2(–3); usually partially joined (at least basally); apical. Stigmas 2(–3). Placentation when syncarpous, apical (from near the top of the septum). Ovules 2–4(–12) per locule; funicled; pendulous; epitropous; with ventral raphe; arillate, or non-arillate; anatropous; unitegmic; crassinucellate. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids pear-shaped.

The fruiting carpel when monomerous, indehiscent; an achene, or nucular. Fruit when syncarpous, dehiscent, or indehiscent, or a schizocarp. Mericarps when schizocarpic, 2, or 3; comprising achenes, or comprising follicles, or comprising nutlets. Fruit when syncarpous/non-schizocarpic, a capsule, or achene-like, or a nut; 1 seeded (when nutlike), or 2 seeded (when capsular). Seeds copiously endospermic; very small. Embryo well differentiated. Cotyledons 2. Embryo straight.

Seedling. Germination phanerocotylar.

Physiology, biochemistry. Iridoids not detected. Proanthocyanidins present. Ellagic acid absent. Aluminium accumulation not found.

Geography, cytology. Cape. Temperate to sub-tropical. South Africa. X = 16 (Staavia).

Taxonomy. Subclass Dicotyledonae; Crassinucelli, or Tenuinucelli (? - embryological and other evidence being conflicting). Dahlgren’s Superorder Rosiflorae; Cunoniales. Cronquist’s Subclass Rosidae; Rosales. APG 3 core angiosperms; core eudicot; Superorder Asteranae; campanulid; Order Bruniales.

Species 75. Genera 12; Audouinia, Berzelia, Brunia, Linconia, Lonchostoma, Mniothamnea, Nebelia, Pseudobaeckea, Raspalia, Staavia, Thamnea, Tittmannia.

Illustrations.
• Technical details: Brunia.
• Technical details: Raspalia (Thonner).