Editing Lepidozamia peroffskyana (section)

===Trunk Boring Weevils:===
Trunk boring weevils, such as ''Melotranes internatus'' (Figure 17) and ''Demyrsus meleoides''
(Figure 16), that are inadvertently introduced into a home garden environment,
can cause massive collateral destruction to seedlings and mature plants in either pots or in the ground.
These weevils are often found in 'sick' or damaged ''L. peroffskyana'' plants in the wild; and sometimes in
healthy plants in habitat locations though they do not appear to cause any permanent damage to such
healthy plants. Unhealthy plants appear to be used as breeding chambers and the resulting larvae feed on
plant tissue, making small tunnels as they proceed, culminating in a honeycomb-type pattern of tunnels
that cause surrounding areas of the caudex to begin to rot with the ultimate effect on the plant being
terminal.
 
In a home garden environment, the first obvious sign of weevil predation normally occurs when an
apparently healthy plant suddenly collapses at ground level, because the caudex has totally rotted.
The damage that can be caused to cycads by ''Melotranes internatus'' (previously ''Tranes internatus'')
was the subject of an article on "Cycad-Insect Relationships" which I contributed to Issue No 34 of "Palms &
Cycads."  In this article mention was made of a report that appeared in Volume 3, Issue No 2 of the
Cycad Newsletter in February 1982, concerning the arrival of a weevil (then) identified as
''Tranes internatus'' into the U.S. in the late 1960's and 1970's in the caudices of
Australian Macrozamias and to significant problems that subsequently occurred in Los Angeles.
The above report indicated that these weevils were unaffected by their host caudex being subjected to
methyl bromide fumigation. Obviously, the methyl bromide had not penetrated deep enough in the
caudices to affect the weevils.

Further historical evidence of the activities of ''Melotranes internatus''
is available by reference to an article
written, over 120 years ago, in 1886, by J. O. Westwood in a Belgian Entomology Journal. In his article,
Westwood described the ravages caused by larvae (then) identified as ''Tranes internatus'' which had been
found in the caudex of an imported Australian cycad in the city of Ghent. The relevant plant which was
described as "Zamia corallipes" was probably either ''M. spiralis'' or ''M. communis'', though there is
insufficient evidence in the article to now positively identify the particular Macrozamia species involved.
''Melotranes internatus'' was thus capable of surviving a lengthy surface voyage to Europe in the 1880's
and, also, withstanding methyl bromide fumigation treatment after caudices were imported into the
U.S.A and, in both situations, was able to reproduce in a new and different environment.
 
Three conclusions about ''Melotranes internatus'' can be drawn from the above:

<ol><li> that adult weevils live deep inside cycad caudices, possibly in tunnels created by larvae, and can resist most normal insecticide/fumigation treatments,
</li><li> that when removed from their own environment, the weevils are isolated from their natural enemies (if any) and are able to freely multiply, and
</li><li> that there may be an extremely long interval of time between the arrival of ''Melotranes internatus'' in a home garden and its emergence as an identifiable problem.
</li></ol>

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[[File:Lepidozamia_peroffskyana18.jpg|frame|Figure 16. ''Demyrsus meleoides'' weevil specimen.]]
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[[File:Lepidozamia_peroffskyana17.jpg|frame|Figure 17. ''Melotranes internatus'' weevil and larva.]]
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Care should be taken to prevent these weevils from being introduced into a home garden environment by
avoiding purchasing (or otherwise acquiring) plants that are suspected of having been taken from the
wild. In addition, a careful examination of nursery-bought plants should also be undertaken before they
are introduced into a home garden environment.
Having seen evidence of ''Melotranes internatus'' on ''L. peroffskyana'' plants, it is my opinion that the
purchase of ''L. peroffskyana'' plants taken from the wild (or the taking of any cycads from the wild) is
somewhat like a lottery, with the chance that if you happen to end up with a plant that is infested with
''Melotranes internatus'', you may unknowingly have a mini-ecological 'time bomb' on your hands.