Family Salvadoraceae

Salvadoraceae Lindl.

Habit and leaf form. Trees, or shrubs (sometimes spinose, with axillary spines). Self supporting, or climbing; when scandent, scrambling. Xerophytic (of hot, dry, often coastal or saline regions). Leaves opposite; ‘herbaceous’, or leathery (usually olive grey); not gland-dotted; simple. Lamina entire. Leaves stipulate (often, but the stipules rudimentary), or exstipulate (?). Lamina margins entire.

Leaf anatomy. Stomata present; anomocytic, or anisocytic, or paracytic.

Adaxial hypodermis present, or absent. Lamina dorsiventral, or isobilateral. The mesophyll containing calcium oxalate crystals (but not oxalate). The mesophyll crystals druses. Minor leaf veins without phloem transfer cells (Salvadora).

Stem anatomy. Cork cambium present; initially superficial. Primary vascular tissue comprising a ring of bundles. Internal phloem absent. Secondary thickening anomalous; from a single cambial ring. ‘Included’ phloem present. Xylem without fibre tracheids; with libriform fibres. Vessel end-walls simple. Wood storied, or partially storied (VPI); parenchyma paratracheal.

Reproductive type, pollination. Plants hermaphrodite, or dioecious, or polygamomonoecious, or polygamodioecious.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in fascicles, or in panicles. The ultimate inflorescence unit mostly racemose. Inflorescences terminal, or axillary; of various sorts, axillary or terminal, mostly indeterminate. Flowers small; regular; mostly 4 merous; cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk present, or absent; intrastaminal; when present, of separate members (represented by small glands alternating with the stamens).

Perianth with distinct calyx and corolla; (6–)8(–10); 2 whorled; isomerous to anisomerous. Calyx 2–4(–5); 1 whorled; gamosepalous; blunt-lobed; regular; imbricate, or valvate. Corolla 4(–5); 1 whorled; appendiculate (with teeth or small glands on the inside — these representing staminodes?), or not appendiculate; polypetalous, or gamopetalous (shortly connate at the base in Salvadora). Corolla lobes markedly longer than the tube. Corolla imbricate, or contorted; regular.

Androecium 4(–5), or 8(–10). Androecial members adnate, or free of the perianth and adnate; free of one another, or coherent (the stamens connate below into a tube, in Dobera); 1 whorled, or 2 whorled. Androecium exclusively of fertile stamens, or including staminodes (often, if teeth or glands inside the corolla are taken to be staminodal). Staminodes if present, 4(–5). Stamens 4(–5); isomerous with the perianth; oppositisepalous. Anthers dehiscing via longitudinal slits; bilocular (the loculi back to back); tetrasporangiate. Pollen shed as single grains. Pollen grains aperturate; 3 aperturate (usually), or 6 aperturate; colporate (usually tricolporate), or rugate (exceptionally 6-rug(or)oidate).

Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled, or 2 celled. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; superior. Ovary 1 locular (Dobera, Salvadora), or 2 locular (Azima). Gynoecium shortly stylate. Styles 1; apical; shorter than the ovary. Stigmas 1, or 2; entire or two-lobed. Placentation when unilocular, basal; when bilocular, basal to axile. Ovules in the single cavity 1–2; 1–2 per locule; ascending; apotropous; with ventral raphe; anatropous; bitegmic; crassinucellate. Outer integument not contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3 (large); not proliferating. Synergids pear-shaped. Endosperm formation nuclear.

Fruit fleshy; indehiscent; a berry, or a drupe. The drupes with one stone. Fruit mostly 1 seeded. Seeds non-endospermic. Embryo well differentiated. Cotyledons 2; plano-convex, cordate, oily.

Physiology, biochemistry. Mustard-oils present. Cyanogenic. Alkaloids present, or absent. Iridoids not detected. Proanthocyanidins absent. Flavonols present; quercetin. Ellagic acid absent (Salvadora). Aluminium accumulation not found. C3. C3 physiology recorded directly in Salvadora. Anatomy non-C4 type (Salvadora).

Peculiar feature. Lamina tip not abaxially pouched.

Geography, cytology. Paleotropical. Sub-tropical to tropical. Africa, Madagascaar, Southern Asia, Malaysia. X = 12.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Violiflorae; Salvadorales (or Capparidales). Cronquist’s Subclass Rosidae; Celastrales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Brassicales.

Species 12. Genera 3; Azima, Dobera, Salvadora.

Illustrations.
• Technical details: Salvadora.