Common name. Saltwort Family.
Habit and leaf form. Weak, straggling coastal shrubs (to 150 cm high). Plants succulent. Young stems tetragonal. Xerophytic. Leaves small; opposite; fleshy; subsessile to sessile; strong-scented; simple. Leaf blades entire; flat, or solid (flat above, convex below); linear, or oblong, or obovate. Leaves without stipules. Vegetative buds not scaly. Stem anatomy. Secondary thickening absent, or developing from a conventional cambial ring.
Reproductive type, pollination. Fertile flowers functionally male and functionally female, or functionally male, or functionally female. Unisexual flowers present. Plants monoecious, or dioecious. The unisexual flowers when monoecious, segregated in different inflorescences. Male flowers with pistillodes, or without pistillodes.
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in spikes. The terminal inflorescence unit racemose. Inflorescences axillary; conical, strobiloid spikes with flowers in four ranks. Flowers bracteate (the bracts cochleariform and imbricate in male inflorescences, smaller and partially incorporated in the fleshy female spike); small; those of male plants somewhat irregular to very irregular; male flowers zygomorphic. The floral asymmetry of male flowers involving the perianth. Flowers (male) 4 merous; male flowers cyclic. Free hypanthium absent. Hypogynous disk absent. Perianth with distinct calyx and corolla (in male flowers), or absent (in female flowers, where the lower bracts are united); of male flowers 2 -whorled. Calyx of male flowers 1 -whorled; gamosepalous; blunt-lobed; cupuliform, or campanulate; bilabiate. Corolla of male flowers 4; 1 -whorled; polypetalous, or gamopetalous (the claws more or less united); regular. Petals clawed. Fertile stamens present, or absent (from female flowers). Androecium of male flowers 4. Androecial sequence not determinable. Androecial members free of the perianth; all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 4; isomerous with the perianth; oppositisepalous (at least, alternating with the corolla). Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Fertile gynoecium present, or absent (from male flowers). Gynoecium of female flowers 2 carpelled (but secondarily partitioned from each carpel midrib). The pistil 4 celled. Carpels reduced in number relative to the perianth. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior (but the 8–10 gynoecia of adjoining flowers coherent, and adherent to the bract bases). Ovary plurilocular; 2 locular (but partitioned into locelli). Locules secondarily divided by ‘false septa’. Ovary sessile. Gynoecium non-stylate. Styles 1. Stigmas 2 (sessile). Placentation basal. Ovules 1 per locule; funicled; ascending; anatropous.
Fruit and seed features. Fruit fleshy; indehiscent; a drupe. The drupes with separable pyrenes (four). Gynoecia of adjoining flowers combining to form a multiple fruit. The multiple fruits coalescing. Seeds non-endospermic. Embryo well differentiated. Cotyledons 2. Embryo straight. Seedling. Germination phanerocotylar.
Physiology, biochemistry. Mustard-oils present. Photosynthetic pathway: C3.
Geography, cytology, number of species. Paleotropical, Neotropical, and Australian. World distribution: Pacific, West Indies, north coastal South America, central America to Florida, New Guinea, Queensland. = 9. 2 species.