Habit and leaf form. Trees, or shrubs; evergreen; non-laticiferous and without coloured juice. Plants non-succulent; unarmed. Mesophytic, or xerophytic. Leaves small to medium-sized; alternate; spiral; leathery; petiolate. Petioles wingless. Leaves non-sheathing; gland-dotted, or not gland-dotted; simple. Leaf blades entire; pinnately veined. Leaves with stipules (inconspicuously). Stipules scaly; caducous. Leaf blade margins entire, or crenate. Leaves without a persistent basal meristem. Leaf anatomy. Hairs present; glandular hairs absent; complex hairs absent. Branched hairs absent. Urticating hairs absent. Extra-floral nectaries absent. Stem anatomy. Nodes tri-lacunar, or unilacunar. Secondary thickening developing from a conventional cambial ring, or anomalous; from a single cambial ring.
Reproductive type, pollination. Fertile flowers functionally male, or functionally female. Unisexual flowers present. Plants dioecious. Female flowers aggregated in ‘inflorescences’; without staminodes. Male flowers aggregated in ‘inflorescences’; without pistillodes, or with pistillodes (obscure, or exceptionally developed as an irregularly bilobed structure). Entomophilous.
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence few-flowered. Flowers when aggregated, in racemes, or in fascicles. Inflorescences simple; axillary. Flowers pedicellate, or sessile (sometimes in females); bracteate; minute to small; regular. Floral receptacle developing an androphore (androphore shortly conical), or with neither androphore nor gynophore (? depending on interpretation). Free hypanthium absent. Hypogynous disk absent. Perianth sepaline; 4–8; 1 -whorled, or 2 -whorled (the outer whorl, when present, longer and narrower than the inner whorl); isomerous, or anisomerous. Calyx present; 4–8; 1 -whorled, or 2 -whorled; polysepalous; erect, or spreading; at least sometimes hairy; imbricate; non-fleshy; not persistent (on female flowers). Corolla absent. Androecium present, or absent. Fertile stamens present, or absent (female flowers). Androecial members indefinite in number. Androecium 18–86. Androecial members branched; free of the perianth; coherent (shortly connate into a column). Androecium exclusively of fertile stamens. Stamens 18–86; all more or less similar in shape; polystemonous; erect in bud, or inflexed in bud. Filaments not geniculate. Anthers all alike; dorsifixed; dehiscing via longitudinal slits; extrorse; bisporangiate, or tetrasporangiate. Fertile gynoecium present, or absent (male flowers). Gynoecium 3 carpelled, or 4 carpelled. The pistil 3 celled, or 4 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; synovarious, or synstylovarious; superior. Ovary plurilocular; 3 locular, or 4 locular. Gynoecium stylate. Styles 3, or 4; free (each expanded, petal-like and sometimes lobed towards the apex); simple; apical; becoming exserted; deciduous; hairless. Stigmas 3, or 4; expanded, petal-like and sometimes lobed towards the apex; dry type; papillate, or non-papillate; Group II type. Placentation axile, or apical. Ovulodes absent. Ovules 2 per locule; pendulous; epitropous; with ventral raphe, or with dorsal raphe; collateral; arillate; anatropous.
Fruit and seed features. Fruit fleshy; yellow, or yellow to red; hairy; dehiscent, or a schizocarp (with a succulent exocarp and a hard endocarp). Mericarps 3, or 4. Fruit when dehiscent, a capsule (globular to ovoid). Capsules septicidal. Fruit 3 celled, or 4 celled; 3 locular, or 4 locular; elastically dehiscent (schizocarpic capsules often splitting elastically), or passively dehiscent. Seeds 1 per locule, or 2 per locule; 2 or more per mericarp. Seeds ovoid to ellipsoid, slightly compressed; endospermic. Endosperm oily. Seeds arillate. Cotyledons 2 (usually wider than the radicle). Embryo straight, or curved. Testa hard; smooth; homogeneous in colour; brown, or red. Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Mustard-oils present, or absent.
Geography, cytology, number of species. World distribution: Australia and New Guinea. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, Northern Territory, Queensland, and New South Wales. Northern Botanical Province. A genus of 6 species.
Additional characters Perianth of male flowers sepaline; 4. Perianth of female flowers sepaline; 6–8.
FloraBase is produced by the staff of the Western Australian Herbarium, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions. Publication or other use of content on this site is unauthorised unless that use conforms with the copyright statement.
Western Australian Herbarium (1998–). FloraBase—the Western Australian Flora. Department of Biodiversity, Conservation and Attractions. https://florabase.dpaw.wa.gov.au/