| Distribution | Small region in southeastern Namibia | Warm-temperate and tropical coasts in the American Atlantic, Central American Pacific, Galapagos and the Timor Sea in Australia and Indonesia | Old World, especially Africa, Madagascar, Arabia and India | Southwestern North America, with disjunct population in Bolivia |
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| Habitat | Hot, arid, calcareous seasonal pans in semi-desert region | Marine habitats: salt marshes, mangroves, beaches, sand bars and coasts | Warm, arid, often on somewhat saline soils | Warm, arid, semideserts and deserts |
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| Habit | Xerophytic dwarf shrubs, up to 0.8 m tall | Succulent shrubs, often scrambling | Shrubs or trees, sometimes scrambling or scandent | Xerophytic shrubs or small trees |
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| Plant sex (sensu Bawa 1980) | Hermaphroditic | Monoecious or dioecious | Hermaphroditic or dioecious (Azima) | Hermaphroditic |
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| Glucosinolates | Present (presence of myrosin cells still to be confirmed) | Present (myrosin cells present) | Present (myrosin cells absent) | Apparently absent (although myrosin cells present) |
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| Stems | Distinctly differentiated into long and short shoots | Mainly long shoots | Mainly long shoots | Mainly long shoots |
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| Thorns/spines | Stem of weathered old short shoots sometimes persisting as a short thorn or blunt projection | Absent | Absent or present (spines) | Present (thorns) |
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| Foliage leaves |
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| Duration | Evergreen | Evergreen | Evergreen | Drought-deciduous |
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| Size and texture | Dimorphic; minute, scale-like, leathery or semi-succulent | Monomorphic; succulent, ca. terete; bracts of cone-like spikes scale-like | Monomorphic; leathery or semi-succulent, never scale-like | Monomorphic; minute, scale-like, leathery |
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| Stipules | Absent | Present (minute, early deciduous) | Present (minute) | Absent |
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| Arrangement | Alternate, spiral, dense | Opposite, well-spaced; bracts decussate, dense | Opposite, well-spaced | Alternate, spiral, wellspaced |
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| Inflorescences | Flowers borne solitarily in axils of bracts on short shoots | Axillary or terminal cone-like spikes | Axillary or terminal racemes, paniculate or axillary fascicles | Short, axillary, umbel-like racemes |
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| Flowers |
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| Sex | Bisexual | Unisexual | Bisexual or unisexual | Bisexual |
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| Symmetry | Actinomorphic, but laterally compressed | Actinomorphic, laterally compressed (disymmetric) | Actinomorphic, laterally compressed at least in early stages | Actinomorphic |
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| Sepals | 4, fused with free lobes | 2, fused, split into two lobes in males; absent in females | 2–4(–5), fused into a short tube | 4, free |
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| Petals | 4, free, sessile | 4, free, long clawed in males; absent in females | 4(–5), basally fused, sessile | 4, free, slightly clawed |
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| Stamens | 4, free | 4, free | 4(–5), free or basally fused (sometimes with petals) into a short tube | 8(–10), free |
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| Nectar gland (disk-like) | Present (?), 4-lobed, each lobe continuing as a stamen; alternatively interpreted as a receptacle | Absent | Absent | Absent |
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| Nectar glands (separate) | Absent | Absent | Often present, scale-like, ventrally at base of petals | Present, scale-like, at base of stamens |
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| Ovary (form) | Deeply bilobed; bilocular; horizontally orientated, occasionally inverted | Not lobed; tetralocular; upright | Not lobed; uni- or bilocular; upright | Not lobed; bilocular; upright |
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| Gynophore | Present, erect in very young flowers, near S-shaped in mature ones | Absent | Absent, or if present, short and straight | Present, straight |
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| Ovules | 2 per locule | 1 per locule | 1 or 2 per locule | Many per locule |
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| Style | Well developed, elongate, deeply inserted between lobes of ovary (gynobasic) | Short, apical; stigma subsessile | Short, apical | Short, apical |
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| Fruit (type) | Dry, papery (enclosed in persistent calyx); 1-seeded nutlet (?) | Drupe or drupaceous syncarp, each with 4 pyrenes | Drupe or berry; 1-seeded | Berry; 1- or 2-seeded |
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