Family Papilionaceae. Mirbelieae.
Sometimes included in Leguminosae.
Habit and leaf form. Shrubs. Leaves cauline. Plants with neither basal nor terminal concentrations of leaves. Leaves alternate (usually), or whorled; when verticillate, 3 per whorl; not decurrent on the stems; petiolate, or subsessile, or sessile; non-sheathing; simple; epulvinate. Leaf blades dorsiventral; entire; flat, or folded, or rolled, or solid; when ‘solid’, terete, or semi-terete, or solid/angular; grooved adaxially, or grooved abaxially, or not grooved. Leaves with stipules (usually), or without stipules. Stipules free of one another, or concrescent (commonly); setaceous, subulate or scarious; caducous, or persistent. Leaf blade margins flat, or revolute, or involute.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Entomophilous.
Inflorescence and flower features. Flowers solitary, or aggregated in ‘inflorescences’ (usually); not crowded at the stem bases; when solitary, terminal, or axillary; when aggregated, in heads, or in fascicles. Inflorescences terminal; generally in terminal heads, or axillary clusters — then often crowded towards the ends of the branches; with involucral bracts (i.e. often surrounded by persistent, leafy or scarious stipules or bracts), or without involucral bracts; pseudanthial, or not pseudanthial. The involucres non-accrescent. Flowers pedicellate to sessile; bracteate (the bracts frequently with stipules that are broader and more scarious than those of the foliage leaves, and sometimes with their lamina reduced or absent); (bi-) bracteolate. Bracteoles persistent (either close under or adnate to the calyx). Flowers very irregular; zygomorphic. The floral asymmetry involving the perianth, or involving the perianth and involving the androecium. Flowers papilionaceous; tetracyclic. Floral receptacle developing a gynophore, or with neither androphore nor gynophore. Free hypanthium present, or absent. Hypogynous disk present; intrastaminal; annular. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; five lobed. Calyx lobes about the same length as the tube to markedly longer than the tube. Calyx exceeded by the corolla; bilabiate (the posterior pair of members generally broader and/or more connate); non-fleshy; persistent; non-accrescent; with the median member anterior. Epicalyx present (in the form of adnate bracteoles), or absent. Corolla present; 5; alternating with the calyx; appendiculate, or not appendiculate. Standard not appendaged. Corolla polypetalous, or partially gamopetalous. Corolla lobes about the same length as the tube. 2 of the petals joined. The joined petals anterior (the keel pair). The wings of the corolla free from the keel; not laterally spurred. Standard ‘normally’ developed; slightly emarginate. Keel incurved; not long-acuminate/beaked; neither coiled nor spiralled; not bent and beaked. Corolla imbricate; yellow, orange, red, and brown (in combinations, the keel often darker); deciduous; non-accrescent. Petals clawed. Androecial members definite in number. Androecium 10. Androecial sequence determinable, or not determinable. Androecial members free of the perianth; all equal to markedly unequal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 10; all more or less similar in shape; diplostemonous; both opposite and alternating with the corolla members; filantherous. Anthers separate from one another to connivent; all alike; dehiscing via longitudinal slits; latrorse, or introrse; tetrasporangiate. Gynoecium 1 carpelled. The pistil 1 celled. Carpels reduced in number relative to the perianth. Gynoecium monomerous; of one carpel; superior. Carpel stylate. Style subulate, filiform or basally dilated, straight, or curved, or hooked (rarely). Style hairy but not bearded, or glabrous. Stigmatic tissue terminal. Carpel 2 ovuled. Gynoecium median. Ovary sessile to subsessile (‘sessile or rarely shortly stipitate’). Stigmas punctiform (? — ‘small’). Ovules shortly funicled.
Fruit and seed features. Fruit sessile; non-fleshy. The fruiting carpel dehiscent; a legume. Pods globose to somewhat elongated (ovate in outline); not triangular; straight; becoming inflated, or not becoming inflated; more or less flat, or somewhat compressed, or terete; not constricted between the seeds; not transversely septate. Fruit 1 celled. Dispersal unit the seed. Fruit 1–2 seeded. Seeds ellipsoid or reniform in outline; not mucous; arillate. Embryo bent (radicle inflexed). Testa non-operculate.
Geography, cytology, number of species. Native of Australia. 2n = (8, 12) 14, 16, 18 (27, 32). A genus of about 100 species; 27 species in Western Australia.