PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
Scientific name
Millipedes belong the Superclass Myriapoda,
Class Diplopoda in the Phylum Arthropoda.
Species include:
Black Portuguese millipede (Ommatoiulus moreletii),
a major pest in South Australia, Tasmania, Victoria and
Western Australia.
Flat brown millipede (Brachydesmus superus)
White millipede (Blaniulus guttulatus)
Numerous native species, eg Dimerogonus
orophilus, Oncocladosoma clavigerum
Some species are not known in Australia, eg the
American giant millipede (Narceus americanus). The
giant African millipede (Archispirostreptus gigas) is
one of the largest millipedes, is up to 28cm long, lives
for 7-10 years and is often kept as a pet.
Most state departments of agriculture/primary industry
have fact sheets on Portuguese Millipedes.
www.csiro.au/resources/BlackPortugueseMillipedes.html
www.ento.csiro.au/education/allies/diplopoda.html ok
Host range
Black Portuguese millipede are not harmful to
humans but can occur in plague numbers, invading
houses, contaminating food and infesting carpet and
bedding. It is one of the few millipede species that
are attracted to lights at night. Once inside they
usually die, they do not breed inside.
Millipedes feed on decaying organic matter but
may attack crops growing in damp soil and are
occasional pests of greenhouses.
Plagues may occur and destroy seedlings and
fruit and vegetable crops Millipedes are
important in soil formation, breaking down leaf
litter and enriching the soil.
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ALLIED PESTS - Millipedes
Class Diplopoda
Table 45. Distinguishing millipedes from centipedes.
Description & damage
Adult millipedes are elongated, dark brown
in colour and up to 30 mm long. They possess:
A bilaterally symmetrical body.
An exoskeleton (outer hard covering to body
and legs).
A segmented body (at least 11 body segments)
which is round in cross section.
10 or more pairs of tiny legs (2 pairs per
segment), no poison fangs.
1 pair of short antennae.
May give off an offensive odour.
Plant damage. Millipedes may chew roots of
plants in containers and pots under damp conditions.
They may also feed on soft leaves, fruit and other
plant material close to the surface of damp soil.
Diagnostics.
Millipedes have 2 pairs of legs per body segment.
The smooth cylindrical body of the Portuguese
millipede distinguishes it from the native variety
common around Adelaide. The latter’s body
segments give it a bumpy look.
Millipedes are often confused with centipedes
(Table 45 below) and occasionally with
wireworms or false wireworms which are the
larvae of beetles which have only 3 pairs of
short legs on the thorax.
Pest cycle
There is no metamorphosis, the young look like
the adults except that they are smaller in size, have
fewer segments and only 3 pairs of legs initially.
There is probably only 1 generation each year. Eggs
are laid singly or in groups in soil, under logs or on
leaf litter. Adults of Portuguese millipedes that
invade houses are probably about 2 years old but
some species of millipedes live much longer.
Millipedes
(Class Diplopoda)
At least 11 body segments.
Round body (in cross section).
‘Thousands’ of legs, two pairs legs per segment,
no poison fangs.
One pair of short, segmented antennae.
Mainly vegetarian.
May have an offensive odour.
Centipedes
(Class Chilopoda)
At least 19 body segments.
Flattened body (in cross section).
‘Hundreds’ of legs (15-181 pairs of legs),
one pair legs per segment, first pair modified to
form poison fangs. Most fast moving and
aggressive.
One pair of antennae.
Almost exclusively predatory.
Millipede
Centipede
214 Insects and allied pests - Millipedes (Diplopoda)