Leaves few to numerous, simply pinnate but the pinnae sometimes dichotomously divided, the rachis straight or twisted; base of the petiole swollen, usually silky or tomentose. Pinnae numerous in mature plants, spreading or turned to one side, inserted near the edges of the rachis towards the upper side. Cones axillary, pedunculate; sporophylls terminated by upturned spines; spines usually largest towards apex of cone.
Male cones ± cylindrical, often curved when old. Female cones ± ovoid, inner parts often bright pink; sporophylls with 2 ovules; sporophylls fall with attached seeds when ripe
Note: juvenile plants may differ considerably from the adult forms in details of the leaves; in particular the pinnae are usually toothed at the ends and the petioles are long and slender. Key abstracted from Johnson (1961).
| | Key to the species | |
| 1 | Large plants with 15–50 leaves in the crown, veins visible but thin and not or scarcely raised on the lower surface when dry, mucilage canals present in pinnae, lower pinnae reduced to spines | 2 |
| Small plants with 2–12 leaves (rarely up to 40 in Macrozamia lucida), veins thick and prominent on the lower surface, especially when dry, mucilage canals not present in pinnae, lower pinnae not reduced to spines | 7 |
| 2 | Pinnae with stomates on both surfaces (amphistomatic) | Macrozamia johnsonii |
| Pinnae with stomates on lower surface only (hypostomatic)
Back to 1 | 3 |
| 3 | Pinnae not dichotomously divided | 4 |
| At least some pinnae dichotomously divided
Back to 2 | Macrozamia diplomera |
| 4 | Pinnae thin, upper surface glossy; spines of female sporophylls slender 2–5 mm wide at base | Macrozamia miquelii |
| Pinnae thick, upper surface dull to semiglossy; spines of female sporophylls broad, over 5 mm wide at base
Back to 3 | 5 |
| 5 | Plants large, leaves >150 cm long, seeds >35 mm long | 6 |
| Plants small, leaves <150 cm long, seeds <30 mm long
Back to 4 | Macrozamia reducta |
| 6 | Petioles spine-free for at least 15 cm | Macrozamia communis |
| Petioles spinescent almost to base
Back to 5 | Macrozamia montana |
| 7 | Rachis not twisted or moderately twisted, if >360°, then petiole 20–40 cm long or pinnae divided | 8 |
| Rachis strongly spirally twisted, if <360° then pinnae entire or petiole 5–15 cm long
Back to 1 | 16 |
| 8 | Pinnae simple | 9 |
| Pinnae dichotomously divided one or more times
Back to 7 | 12 |
| 9 | Pinnae spreading, petiole round or flat above | 10 |
| Pinnae secund, petiole concave above
Back to 8 | Macrozamia secunda |
| 10 | Pinnae glossy, whitish at base | Macrozamia lucida |
| Pinnae dull, pinkish to red or orange at base
Back to 9 | 11 |
| 11 | Leaves 35–100 cm long, pinnae 5–9 mm wide, not pungent | Macrozamia spiralis |
| Leaves 90–150 cm long, pinnae 9–14 mm wide, pungent
Back to 10 | Macrozamia elegans |
| 12 | Pinnae with stomates on one surface only | 13 |
| Pinnae with stomates on both surfaces
Back to 8 | Macrozamia stenomera |
| 13 | Leaves blue to grey-green | Macrozamia glaucophylla |
| Leaves green, or rarely grey-green
Back to 12 | 14 |
| 14 | Pinnae concolorous to weakly discolorous | 15 |
| Pinnae distinctly discolorous
Back to 13 | Macrozamia humilis |
| 15 | Pinnae >5 mm wide | Macrozamia polymorpha |
| Pinnae <5 mm wide
Back to 14 | Macrozamia heteromera |
| 16 | Broadest pinnae <10 mm wide, usually with a single apical tooth | 17 |
| Broadest pinnae >10 mm wide, 2–7-toothed apically
Back to 7 | Macrozamia fawcettii |
| 17 | Leaflets green on lower surface | Macrozamia flexuosa |
| Leaflets grey or glaucous on lower surface, most noticeably in new growth
Back to 16 | 18 |
| 18 | Petioles ± terete | Macrozamia concinna |
| Petioles strongly flattened
Back to 17 | Macrozamia plurinervia |
