Cycads
Lepidozamia peroffskyana II
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| Cones:
Both male and female cones are large and unlike Macrozamia
cones do not have a peduncle.
Female cones are usually solitary, though plants with 2 cones are not uncommon (Figure 6).
Female cones are also the largest cones on any New South Wales cycad, measuring up to 50-60
cms in length and 20-25 cms in width when mature. Additionally, the sporophylls on female cones of
L. peroffskyana
do not have elongated spine-like appendages like those on Macrozamias.
Like female plants, male plants usually have solitary cones, though plants with 2 cones are not
uncommon.
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Figure 6. Two female plants, each with two cones.
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Figure 7. Distended male cone.
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Male cones open up in an unusual spiral fashion and distend when about to shed pollen (Figure 7).
Prior to distending, male cones measure up to 50-60 cms in length and 10-12 cms in width, but
when fully distended can extend to 1 metre in length.
After distending, the sporophylls on the male cones become a breeding chamber for Tranes sp
weevils,
which are ultimately responsible for fertilisation of the female cones. The activities of these weevils
which are attracted in swarm proportions to the male cones (Figure 12) at about the time
they are ready to open up, result in the rapid destruction of the cone (as the sporophylls are consumed by
larvae).
A Tranes
species weevil, Tranes
"lyterioides" is also associated with the pollination of
Macrozamia communis
(Figure 13).
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Seeds:
Seeds of L. peroffskyana
are the largest of any New South Wales cycad and measure up to 6 cms
long and 3 cms in diameter. Seeds are normally red coloured (Figure 8),
but occasionally yellow coloured seeds are produced (Figure 9).
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Figure 8. Female cone with red seeds.
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Figure 9. Female cone with yellow seeds.
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A unique feature of
L. peroffskyana
is its rare capacity to
produce sporophylls holding either 1 or 3 seeds,
as opposed to Macrozamias which only produce 2 seeds per sporophyll. These 3-seed sporophylls
(Figure 10), which are only found in the basal area of a cone, have 2 seeds positioned
normally, with the third seed situated above and in the middle of the other 2 seeds, so as to form a
triangular pattern. Sporophylls with 1 seed (Figure 10), which are only found in apical
section of a cone, are also an unusual feature of this species.
The flesh on the seeds of this species tends to be eaten by kangaroos (which normally drop the seeds in
close proximity to the parent plant, where they often germinate in large numbers) and possums (which
normally drop the seeds under a nearby tree). Rats also eat the kernels after gnawing through the shell,
often leaving quantities of half-shells in a cache under a log.
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Figure 10. 1-seed and 3-seed sporophylls.
Regeneration:
Natural regeneration of L. peroffskyana
in the wild is prolific as evidenced by the large
number of seedling plants that are evident in the immediate vicinity of female plants, though very few of
these seedlings ultimately grow to maturity (Figure 11).
Figure 11. Seedlings growing near a parent plant.
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