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| The Cycad Pages
| | GENUS
Macrozamia
| |
K.D. Hill | |
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| Macrozamia glaucophylla
| Photo Ken Hill |
- Macrozamia Miq., Monogr. Cycad.: 35 (1842);
from the Greek makros, large, and Zamia a genus of cycads.
- Type: M. reidlei (Fisch. ex Gaudich.) C.A. Gardner,
fide L.A.S. Johnson, Proc. Linn. Soc. New South Wales 84: 87 (1959).
38 species, in two sections, all endemic in Australia, with 34 in
eastern Australia, 1 in central Australia and 3 in the south-west.
Recent studies have enumerated a great number of new species,
several of which are rare and inaccessible. All newly described
taxa have not been fully evaluated, and some changes in the
taxonomy of the genus may be expected in the future.
Several species were important food sources for Australian Aborigines,
after extensive processing to remove toxins.
The more abundant species have also been recorded as livestock poisons.
Most species have at some time gone under the common name of
Burrawang, although this is somewhat in error. The word is from the
Dharuk language (the people originally of the Sydney and Illawarra
region), "barawan[g]", referring to Macrozamia communis. The
term Burrawang has since been applied by European writers
to most other Australian cycads (Macrozamia, Lepidozamia
and Cycas)
Distinguishing characters:
- Leaves pinnate
- Leaflets lacking a midrib
- Leaflets with a coloured basal callus
- leaflets not articulated
- Sporophylls not in vertical rows in cones
- Megasporophyll apices extending into a slender upturned spine
Select a species, or go to the
keys to species
Individual species pages will have
literature references and synonyms, and eventually
images
(indicated by I if present),
distribution maps (M),
descriptions (D) and
general notes (N) on the species.
These are not yet all in place for all species, but the database
is slowly growing.
On species pages, click on thumbnail images to see full-screen images.
Genus description:
Habit: dioecious palmlike shrubs with aerial or subterranean,
pachycaul, cylindrical stems, with few to many leaves and persistent leaf bases.
Leaves: pinnate, spirally arranged, interspersed with cataphylls,
lower leaflets often reduced to spines. Longitudinal ptyxis erect,
horizontal ptyxis erect. Leaflets simple or dichotomously divided,
with numerous parallel veins and no distinct midrib, leaflets
inserted near the edges of the rhachis towards the adaxial side,
often with a paler or differently coloured basal gland; stomata
on lower surface only or on both surfaces; epidermal cells elongated
parallel to long axes of leaflets. Leaves pubescent, at least
when young, with branched or simple transparent hairs.
Microsporophylls: spirally aggregated into determinate, stalked
male cones and each with a simple sterile apex, which is often
produced into an upturned spine. Each microsporophyll bearing
numerous microsporangia (pollensacs) on its abaxial surfaces.
Microsporangia opening by slits. Pollen cymbiform, monosulcate.
Megasporophylls: spirally aggregated into determinate, stalked
female cones. sporophylls simple, appearing peltate with a simple
dilated apex or lamina which is often produced into an upturned
spine. Ovules two (rarely three), sessile, orthotropous, inserted
on the inner (axisfacing) surface of the thickened lamina and
directed inwards ("inverted").
Seeds: subglobular to oblong or ellipsoidal, with a red or less
commonly yellow, orange or brown fleshy outer sarcotesta. Endosperm
haploid, derived from the female gametophyte. Embryo straight;
with 2 cotyledons that are usually united at the tips and a very
long, spirally twisted suspensor. Seeds radiospermic; germination
cryptocotular.
Key to species
Two alternative means for identifying species are offered, a
traditional dichotomous key of the kind familiar to
users of botanical texts, and a multiple-entry screen-based
key using the DELTA system.
To use this key, start with one or two characters that are clear.
To refine a query, use the BACK button of your browser,
return to the original query, and gradually add more characters.
- 1 Large plants with 15--150 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 (not reduced in M. mountperriensis or M. longispina) Sect. 1 Macrozamia
1* Small plants with 2--12 leaves (rarely up to 40 in M. lucida), veins thick and prominent on lower surface, especially when dry, mucilage canals not present in pinnae, lower pinnae not reduced to spines Sect. 2 Parazamia
1 Pinnae with stomata on both surfaces (amphistomatic)
- 2 Petiole with numerous spinose pinnae gradually reducing in size to the leaf base and no clear petiole
- 3 Juvenile leaves becoming weakly amphistomatic from about the 5th leaf; adult leaves dull, keeled (opposing pinnae arranged at less than 150 ) 1. M. moorei
3: Juvenile leaves remaining hypostomatic beyond the 20th leaf; adult leaves glossy, flat 2. M. johnsonii
- 2: Petiole with few spinose pinnae and a distinct clear petiole
- 4 Mature leaves green or grey, not glaucous
- 5 Lower female sporophylls usually with short broad spines, upper female sporophylls with long spines (1.5--6 cm), adult leaves green
- 6 Adult leaves keeled, pinnae with a reduced basal gland, usually evident only on the undersurface, male cones 35--60 cm long, female cones 30--50 cm long
- 7 Pinnae 13--18 mm wide, upper male sporophylls with spines less than 25 mm long, upper female sporophylls with spines less than 40 mm long 4. M. dyeri
7: Pinnae 8--14 mm wide, upper male sporophylls with spines more than 50 mm long, upper female sporophylls with spines more than 50 mm long 3. M. fraseri
- 6: Adult leaves flat, pinnae with a broad white to orange basal gland on both sides, male cones 20--40 cm long, female cones 15--30 cm long 5. M. riedlei
- 4: Mature leaves blue, glaucous 6. M. macdonnellii
- 1: Pinnae with stomata on lower surface only (hypostomatic)
- 8 Pinnae not dichotomously divided
- 9 Pinnae thin, glossy above, closely spaced; spines of female sporophylls slender, 2--5 mm wide at base
- 10 Lower 8 or more pinnae reduced to spines
- 11 Upper female sporophylls with reduced spines, less than 15 mm long 7. M. miquelii
11: Upper female sporophylls with spines more than 25 mm long 8. M. cardiacensis
- 10: Less than 6 lower pinnae reduced
- 13 Some reduced pinnae present 9. M. douglasii
13: Lowermost pinnae full-sized
- 14 Pinnae 6.5--9 mm wide 10. M. mountperriensis
14: Pinnae 4--6 mm wide 11. M. longispina
- 9: Pinnae thick, dull, well-separated; spines of female sporophylls broad, 5--12 mm wide at base
- 15 Plants large, leaves more than 150 cm long, seeds more than 35 mm long
- 16 Petiole spine-free for at least 15 cm 12. M. communis
16: Petiole spinescent almost to base 13. M. montana
- 15: Plants small, leaves less than 150 cm long, seeds less than 30 mm long 14. M. reducta
- 8: At least some pinnae dichotomously divided 15. M. diplomera
1 Rhachis not or moderately spirally twisted, if more than 360 , then petiole 20--40 cm long or pinnae divided.
- 2 Pinnae simple
- 3 Broadest pinnae 15--30 mm wide, 15--18 veined, rhachis 13--18 mm wide at lowest pinnae 17. M. platyrachis
3: Broadest pinnae 3--14 mm wide, 5--11-veined, rhachis 3--10 mm wide at lowest pinnae.
- 4 Pinnae hypostomatic
- 5 Pinnae spreading, petiole round or flat above.
- 6 Pinnae glossy, whitish at base 16. M. lucida
6: Pinnae dull, pinkish to red or orange at base
- 7 Leaves 35--100 cm long, pinnae 5--9 mm wide, not pungent 31. M. spiralis
7: Leaves 90--150 cm long, pinnae 9--14 mm wide, pungent 32. M. elegans
- 5: Pinnae secund, petiole concave above 33. M. secunda
- 4: Pinnae amphistomatic
- 8 Leaves and cones green 35. M polymorpha
8: Leaves and cones glaucous 36. M. glaucophylla
- 2: Pinnae dichotomously divided one or more times.
- 9 Pinnae amphistomatic
- 10 Leaves blue 36. M. glaucophylla
- 10: Leaves green
- 11 Pinnae concolorous
- 12 Pinnae more than 5 mm wide 35. M. polymorpha
12: Pinnae less than 5 mm wide 34. M. heteromera
- 11: Pinnae discolorous 37. M. humilis
- 9: Pinnae hypostomatic 38. M. stenomera
- 1: Rhachis strongly spirally twisted, if less than 360 then pinnae entire or petiole 5--15 cm long.
- 13 Pinnae 1--4 mm wide
- 14 Pinnae 2--4 mm wide, arising at 45 or more to rachis; new growth green
- 15 Petioles strongly flattened (more than 2X wider than thick); pinnae lax, drooping in lower half 21. M. pauliguilielmi
15: Petioles not as strongly flattened (less than 2X wider than thick); pinnae stiff, drooping only in upper third 23. M. crassifolia
- 14 Pinnae 1--3 mm wide, arising at about 30 to rachis; new growth bronze 22. M. parcifolia
- 13: Pinnae 4 mm wide or wider
- 16 Broadest pinnae less than 10 mm wide, usually with a single apical tooth
- 17 Leaflets green beneath
- 18 Petiole strongly flattened
- 19 Leaflets concave above
- 20 Pinnae crowded, stiffly erect, 7--21 cm long, 2--6 mm wide 24. M. conferta
20: Pinnae well spaced, lax, 20--60 cm long, 4--9 mm wide 25. M. fearnsidei
- 19: Leaflets flat or convex above 20. M. viridis
- 18: Petiole more or less terete 27. M. flexuosa
- 17: Leaflets grey or glaucous beneath, most noticeably when in new growth
- 21 Petiole more or less terete 26. M. concinna
21: Petiole strongly flattened
- 22 Pinnae glossy above, lax 30. M. cranei
22 Pinnae dull above, more or less erect
- 23 Leaves more than 70 cm long; longest apical spines on microsporophylls more than 1 cm long 28. M. plurinervia
23: Leaves 40--70 cm long; longest apical spines on microsporophylls more than 1 cm long 29. M. occidua
- 16: Broadest pinnae more than 10 mm wide, 2--7-toothed apically
- 25 Leaves dull 18. M. lomandroides
26: Leaves glossy
- 27 Petiole terete (about as broad as thick), long (more than 25% of total leaf) 19. M. fawcetii
27: Petiole flattened (much broader than thick), short (less then 25% of total leaf) 20. M. viridis
