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

MITES (Order Acarina)
Acarina - (akari)
Insects of Southern Australian Broadacre Farming Systems Identification Manual and Education Resource © 2012
Mites are among the most diverse and successful of all the
invertebrate groups. They have exploited an incredible
array of habitats and, because of their small size (most
are microscopic), go largely unnoticed. Many live freely
in the soil or water, but there are also a large number
of species that live as parasites on plants, animals and
some that feed on mould. It is estimated that over 50,000
Acarina species have been described and that a million
or more species are currently living.
Main characteristics
Nymphs
Most resemble adults but are smaller. Some juveniles
only have three pairs of legs, gaining a fourth pair with
their first moult.
Adult forms
While the appearance of mites varies widely, all mites are
wingless. The mouth parts of mites may be adapted for
biting, stinging, sawing, snipping or sucking. Predatory
mites often use their chelicerae to cut through webbing
of spider mites. Mites have four pairs of legs, no external
segmentation of the abdomen and individuals appear
as a single body mass. Mites do not have antennae, they
use their pedipalps and front legs for probing.
Lifecycle
Incomplete metamorphosis.
They can range in size from minute (0.08 mm) up to
20 mm in length.
72
No antennae
present
Wingless
SECTION 4 COMMON Pest, Beneficial and exotic Species
Groups (families) relevant to broadacre
cropping
Redlegged earth mites and blue oat mites (F:
Penthaleidae): These are among the most important
pests of grain crops and pastures in southern Australia.
They are covered in detail in this section on pages 73-77.
Balaustium mite (F: Erythraeidae): The Balaustium mite
attacks a variety of crops and pastures and is covered in
detail in this section on page 78.
Bryobia mites, two-spotted mite and the brown wheat
mite (F: Tetranychidae): These are important pests of
various crops. The two-spotted mite (Tetranychus urticae)
and brown wheat mite (Petrobia latens) are small mites
(< 1 mm in length) that are sporadic pests of cotton,
cereals and lucerne. For further information on the twospotted
mite refer to the Southern Ute Guide (p. 102).
Bryobia mites are covered in detail on page 80.
Wheat curl mite (F: Eriophyidae): The wheat curl mite
(Aceria tosichella) is a tiny cigar-shaped mite that is the
principal vector of the damaging cereal virus, wheat
streak mosaic virus. For further information, refer to the
Southern Ute Guide (p. 103).
Chewing/sucking mouth
parts (chelicerae)
No external segmentation
of body parts (fused)
Four pairs of
legs (adult)