Alternative names: Not Applicable

Description:
Herbs, undershrubs and shrubs, glabrous or with glandular and/or non-glandular hairs, often aromatic; leaves alternate or opposite, simple to variously compound, lacking stipules.

Inflorescence a capitulum developing from the outside inwards, surrounded by an involucre; capitula solitary or aggregated in loose or dense cymose groups or in compound heads; florets more or less sessile on a receptacle, sometimes each subtended by a scale, epigynous, bisexual or unisexual, rarely in unisexual capitula; calyx modified as a pappus consisting of bristles, scales, a scarious cup or ring or absent; corolla sympetalous, either actinomorphic and tubular with a limb of 3-5 valvate lobes, or zygomorphic with the lobes united on one side as a flat ligule, or the outer female florets filiform and tapered to a minutely toothed apex or lacking a corolla; stamens as many as the lobes, alternating with them and inserted on the tube; anthers linear, basifixed, 2-celled, introrse, usually connate or cohering to form a cylinder which is filled with pollen when the floret opens; style with 2 stigmatic branches, in the bisexual florets with hairs or appendages which lift the pollen out of the floret, n sterile florets unbranched, in female florets without appendages; ovary inferior, 1-celled; ovule solitary, anatropous, on a basal placenta.

Fruit an achene, often with a persistent pappus; seed non-endospermic, with a straight embryo; testa thin, often adhering to the pericarp.

Distribution:  The largest angiosperm family, with about 1,100 genera and 25,000 species worldwide; about 200 genera native to Australia.

Biology: The receptacle of the capitulum is the dilated axis or peduncle apex, in shape a disc, hemisphere or cone; in a compound head small capitula are aggregated on an axis called a common receptacle, which may be of various shapes. The involucre consists of 1 or more rows of bracts, usually crowded, enveloping the capitulum like a calyx around a flower. The outer bracts may be leaf-like, but usually all involucral bracts are smaller than the leaves and differ from them in shape and texture. In some Australian genera, (the 'everlastings'), the bracts have conspicuous white or coloured papery appendages analogous to the rays of a radiate capitulum. A capitulum containing only bisexual flowers is homogamous; a heterogamous capitulum has the outer florets female or neuter and sterile, and the inner ones bisexual or functionally male with reduced style branches and abortive achenes. If all florets are tubular or the outer ones filiform or lacking corollas, the capitulum is discoid; if the outer, or ray, florets are conspicuously ligulate, the capitulum is radiate. In a ligulifloral capitulum all the florets are ligulate. The bristles forming the pappus may be simple or smooth, barbellate, with more or less microscopic barbs, or plumose, with the barbs developed into secondary hairs. The pappus may be raised above the seed-containing body of the achene on a rigid beak.

Key to Genera:

The dynamic key to genus is unavailable, link below is a pdf of the original chapter to determine the genus, then you can find the genus in Flora Fact Sheets Compositae Key

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