Description: Erect or prostrate shrubs.
Leaves alternate, deeply pinnatisect or ternately divided and subdivided into flat or terete segments or rarely simple and margins entire.
Inflorescences usually terminal, spike-like and forming ± globose to ellipsoid cone-like structures; each flower sessile within a bract, bracts tomentose outside, closely imbricate, enlarging and becoming woody in fruit. Flowers actinomorphic. Perianth ± tubular; tepals 4 and equally spreading, base of the tube persistent in fruit. Anthers sessile within expanded apical portion of tepals. Hypogonous glands absent. Ovary sessile; ovule 1; style filiform, pollen presenter usually dilated and separated from a bulbous hairy portion ('brush') by a short constriction.
Fruit a nut, shorter than the bracts and covered with longer hairs; infructescence woody, cone-like, ± globose; bracts falling to release the mature fruit.
Distribution and occurrence: World: c. 35 species, endemic Australia. Australia: Qld, N.S.W., Vic., Tas., S.A., W.A.
Text by G. J. Harden Taxon concept:
| Key to the species | |
1 | Leaves usually divided into flat or terete segments, rarely some leaves below inflorescences entire and then leaves linear and less than 5 mm wide | 2 |
| Leaves entire, oblanceolate to linear, more than 5 mm wide | Isopogon fletcheri |
2 | Leaves with segments terete, less than 1 mm diam | Isopogon anethifolius |
| Leaves with segments flat, more than 1 mm wide Back to 1 | 3 |
3 | Perianth more or less silvery-white to creamy-yellowish, densely covered with silky hairs, at least in the upper half | 4 |
| Perianth yellow, glabrous except for terminal tuft of hairs Back to 2 | 5 |
4 | Leaves mostly more than 8 cm long, ultimate segments linear and often more than 10 mm long | Isopogon dawsonii |
| Leaves usually less than 8 cm long, ultimate segments curved towards the leaf axis, usually less than 10 mm long Back to 3 | Isopogon mnoraifolius |
5 | Leaves with segments 1–2 mm wide; prostrate shrub; tuft of hairs on perianth long, conspicuous in bud | Isopogon prostratus |
| Leaves with segments usually more than 3 mm wide; plants erect or spreading; tuft of hairs on perianth small, hairs short Back to 3 | 6 |
6 | Leaves mostly more than 9 cm long; undivided part of leaf usually about twice as long as divided part; segments divaricate, 3–7 mm wide with 3–5 conspicuous veins, tips of segments pungent; perianth c. 8 mm long | Isopogon petiolaris |
| Leaves usually less than 9 cm long; undivided part of leaf more or less equal to length of the divided part; segments not divaricate, 3–5 mm wide, only midvein conspicuous or all veins obscure, tips not pungent; perianth 10–12 mm long Back to 5 | Isopogon anemonifolius |
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