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From November to March, visitors to the Garden will hear the song of the cicada while walking the paths.
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Amphipsalta zelandica
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There is a great number of species; of all different colours, from red, green, yellow and brown. The most impressive
cicadas are the large Amphisalta spp. measuring 19 mm in length. In some years, there can be large numbers
emerging, and near forest edges their song can be deafening.
They also congregate around streetlights, where they will sing throughout the night. The sound-producing organ,
chamber, is located in the abdomen. Muscles flex the wall of this chamber to produce a sound in the same manner
as a popping tin can. The sound is altered through elevation of the flaps on the under surface of the abdomen.
The song of the cicada is complex and very varied between species.
Cicada nymphs feed on the xylem of plant roots, and in the Amphisalta spp. the nymphs probably take between five
to eight years to reach full development. Cicadas are found right throughout New Zealand, and those in alpine areas,
like the grasshoppers, have restricted distributions, probably for the same reasons.
There are a number of cicadas throughout the country, and found locally. The giant cicada is a handsome insect
with a wingspan of about 75 mm (3 inches). The body is green with black markings and on the fore part of the head
there are three red eyes like jewels, set between the two larger compound eyes. This cicada has a loud chirping
song that ends with a click caused by a flick of the wings. On a hot summer's day the air seems to crackle with
the volume of sound produced by hundreds of these insects singing together.
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Amphipsalta zelandica
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Perhaps the strangest fact concerning cicadas is that only the males are capable of producing sound, and in this
connection one cannot help admiring the daring of the obviously "hen-pecked" Greek poet, Xenarchus, who
wrote:—
"Happy are cicadas' lives,
for they have only voiceless wives."
The larvae burrow into the ground, where they extract juices from the roots of trees. When fully grown the larva
becomes clothed in a horny armor and has rudimentary wings. On reaching maturity it leaves the ground, climbs a
few feet up a tree trunk and finally the perfect insect emerges, leaving the light brown horny case attached to
the tree trunk.
Cicada song is synonymous with the warmer months of New Zealand. There is a great number of species, of all different
colours, from red, green, yellow and brown. In some years, there can be large numbers emerging, and near forest
edges their song can be deafening. They also congregate around streetlights, where they will sing throughout the
night. The sound-producing organ, chamber, is located in the abdomen. Muscles flex the wall of this chamber to
produce a sound in the same manner as a popping tin can. The sound is altered through elevation of the flaps on
the under surface of the abdomen. The song of the cicada is complex and very varied between species.
Eggs are laid in slits of branches. Young nymphs fall to the ground, and burrow down to the roots of trees,
where they attaché themselves. Cicada nymphs feed on the xylem of plant roots, and in the Amphisalta
spp. the nymphs probably take between five to eight years to reach full development. Cicadas are found right throughout
New Zealand, and those in alpine areas, like the grasshoppers, have restricted distributions, probably for the
same reasons.
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Amphipsalta zelandica head
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LOCAL SPECIES:
Usually the loudest cicadas come out in the beginning of February. Wellington has two species of cicada, which
look and sounded alike but appear at different times of the season. The vagaries of Wellington's summer influences
exactly when they appear. The big black ones come out before Christmas, but the second one doesn't come out till
February. The latter species, Amphipsalta zelandica, makes up for its tardiness by being louder and greater
in numbers than Amphipsalta cingulata, which was found only in the North Island. A fine groove on the front
of the head distinguishes one from the other. The song is different between the two but most people wouldn't pick
it out. They both have clicks that go along with the song. The first one that comes out goes a bit like "yackety
yackata" while the second one has more of a “zzz" sound.
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