Habit and leaf form. Perennial shrubs, or trees; evergreen; laticiferous (white). Plants unarmed. Leaves cauline. To 2–8 m high. Mesophytic. Not heterophyllous. Leaves medium-sized, or large; opposite; ‘herbaceous’ to leathery; petiolate; simple. Leaf blades dorsiventral; entire; linear, or ovate, or obovate, or elliptic; pinnately veined; cuneate at the base. Mature leaf blades adaxially glabrous, or pubescent (with simple basifixed hairs); abaxially glabrous, or pubescent (with simple basifixed hairs). Leaves without stipules. Leaf blade margins entire. Leaf anatomy. Hairs present; glandular hairs absent. Unicellular hairs present. Complex hairs absent. Branched hairs absent.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence many-flowered. Flowers in cymes. Inflorescences axillary. Flowers pedicellate; bracteate; small; fragrant; regular; 5 merous; tetracyclic. Hypogynous disk absent. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; lobed (lobes are deeply divided); lobulate. Calyx lobes markedly longer than the tube. Calyx erect; hairy; exceeded by the corolla; regular. Calyx lobes ovate, or obovate. Corolla present; 5; 1 -whorled; gamopetalous; lobed; lobulate. Corolla lobes markedly shorter than the tube, or about the same length as the tube. Corolla contorted (sinistrorse in bud); more or less hypocrateriform; regular; glabrous abaxially; hairy adaxially (with indumentum); plain; cream. Corolla lobes ovate, or obovate. Androecial members definite in number. Androecium 5. Androecial members adnate (epipetalous); all equal; free of one another; 1 -whorled. Stamens 5. Staminal insertion in the throat of the corolla tube. Stamens all inserted at the same level; remaining included; all more or less similar in shape; isomerous with the perianth; oppositisepalous; all alternating with the corolla members. Anthers all alike; dehiscing via longitudinal slits. Gynoecium 2 carpelled. The pistil 2 celled. Gynoecium syncarpous (the carpels united only by their styles); eu-syncarpous; superior. Ovary plurilocular; 2 locular. Gynoecium stylate. Styles 1. Stigmas 1. Placentation axile. Ovules 30–50 per locule (i.e. ‘many’ in 3 or 4 rows).
Fruit and seed features. Fruit 19–40 mm long; non-fleshy; a schizocarp. Mericarps comprising follicles (dehiscent along adaxial suture). Dispersal unit the seed. Fruit 1–50 seeded (1 to ‘many’). Seeds not compressed (oblong); small; not conspicuously hairy; wingless.
Geography, cytology, number of species. World distribution: Africa, Madagascar, Asia, Malesia, Melanesia and Australia. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, Northern Territory, and Queensland. Northern Botanical Province. A genus of c. 110 species; 1 species in Western Australia; 0 endemic to Western Australia.
Additional comments. Etymology: named in honour of James Theodore, surnamed Tabernaemontanus, from Berg-Zabern, the place of his birth; Synonym: Ervatamia.
Etymology. In honour of James Theodore, surnamed Tabernaemontanus, from Berg-Zabern, the place of his birth.