Insects of Southern Australian Broadacre Farming Systems - Grains ...

BUGS (Order Hemiptera)
Hemiptera - half (hemi); wing (ptera)
The order Hemiptera is divided into three groups
(suborders) each with distinct features:
• Auchenorrhyncha (leaf hoppers) - pairs of wings
similar in structure (not shape);
• Heteroptera (e.g. nabids, assassin bugs and shield
bugs) - forewings have half of the wing thickened
(hardened) to form a hard leathery cover and a softer
membranous rear wing;
• Sternorrhyncha (e.g. aphids, scale insects, lerps and
mealy bugs) - pairs of wings similar in structure (not
shape). Some can be wingless.
There are 6,000 hemipteran species described in Australia,
in 100 different families.
Main characteristics
Nymphs
Most resemble adults but are smaller, wingless and less
developed.
Adult forms
While the appearance of bugs varies widely, most bugs
have two pairs of wings. Some adult forms are wingless
(e.g. aphids). Bugs have piercing and sucking mouthparts
which are often modified to form a hardened stylet/
rostrum/proboscis or beak. The proboscis of bugs
contains cutting blades and a two-channelled tube.
Bugs feed by cutting into a plant or animal and sending
saliva down one of the tubes to begin digestion. The
liquid food is then sucked up the other tube. When
insects are resting, the proboscis is often tucked up
under the body between the legs.
Lifecycle
Incomplete metamorphosis.
Groups (families) relevant to broadacre
cropping
Aphids (F: Aphididae): There are many pest aphid
species, including a key biosecurity threat. Aphids are
covered in detail in this section on page 34.
Leafhoppers (F: Cicadellidae): Leafhoppers are
generally small, green insects that puncture leaves and
may leave a pattern of bleached marks. They are minor
and sporadic pests in broadacre crops. Leafhoppers are
not covered in this manual. For further information refer
to Ute Guides, Southern (p. 80)/Western (p. 61).
Mirids (SF: Miridae): Mirids are similar to leaf hoppers.
Some mirids are predatory. Mirids are not covered in
this manual. For further information refer to Ute Guides,
Southern (p. 69)/Western (p. 51).
Seed Bugs (SF: Lygaeoidea): Rutherglen bug (Nysius
vinitor) belongs to this family and it is a common but
sporadic native pest in broadacre crops. It can breed
abundantly, if rain allows flowering and seed set of
plants in warm weather. Nymphs are different in colour
and shape to adults. Seed bugs are not covered in this
manual. For further information on Rutherglen bugs
refer to Ute Guides, Southern (p. 65)/Western (p. 49).
Shield and stink bugs (F: Pentatomidae): This family
contains both beneficial insects (e.g. the glossy shield
bug, Cermatulus nasalis) and some sporadic pests, which
are more common in warmer climates (e.g. the green
vegetable bug, Nezara viridula). Shield and stink bugs
are not covered in this manual. For further information
refer to Ute Guides, Southern (pp. 66-68)/Western
(p. 50, 117, 118).
Nabids (F: Nabidae): These bugs are predators, attacking
a wide range of prey. Nabids are also called damsel bugs
and tend to be more delicate in structure than assassin
bugs. Nabids can also eat plants and are regarded as
omnivores. They are covered in this section on page 47.
Assassin bugs (F: Reduviidae): These bugs are predators,
attacking a wide range of prey. Assassin bugs are not
covered in this manual. For further information refer to
Ute Guides, Southern (p. 142)/Western (p. 120).
SECTION 4 COMMON Pest, Beneficial AND EXOTIC Species
33
Insects of Southern Australian Broadacre Farming Systems Identification Manual and Education Resource © 2012