Research on mites or Acarina is increasing our knowledge of their diversity, biology and behaviour. Mites are not insects, but arachnids, a group that also includes spiders, scorpions and harvestmen, and a few other groups of small invertebrates.
Understanding and identifying new species of mites
Mites occur in all imaginable habitats – in soil and water, on the bottom of the sea, and on plants and the bodies of other animals. Most mites are small, less than 1 mm in length, so they often go unnoticed until they make their presence felt in some way.
About half a million species are believed to exist worldwide, but the great majority have never been studied or even named. About 3 000 named species occur in Australia, but the actual number of species present is certainly much greater than that.
Some of the best known mites are plant pests, both in domestic gardens and in agriculture. They damage plants by piercing the leaves and sucking out the sap. This can cause plants to wilt and die, and can cause serious crop losses. Other mites transmit plant diseases. Others are very valuable predators that are used as biological control agents of plant pests.
Parasitic mites that come into direct contact with humans and livestock can cause diseases including mange and scabies. Some species that occur in house dust can cause allergy and asthma in humans. Many species of mites occur in stored food, where they contaminate food and can be an irritant to workers in the stored food industry.
The most abundant beneficial mites are more obscure. These occur in large numbers in soil, leaf litter and other decomposing organic material, where they help in returning nutrients to the soil.
Investigating their environmental and economic importance
The team at CSIRO are increasing our knowledge of mite diversity, its biology and their behaviour.
Current activities include studies of the taxonomy and biology of predatory mites that occur in soil. Some species appear to be involved in symbiotic relationships with other soil animals, such as beetles and spiders.
We are also working on a long-term program to document the Australian fauna of Uropodina, in collaboration with colleagues in Poland. The Uropodina are very abundant and diverse in leaf litter, soil, and caves, however up until now the Australian fauna has yet to be studied in a systematic way.
One of the most important products from the mite laboratory is the mite section of Australian Faunal Directory. This is a catalogue of all the mites that are known to occur in Australia, with details of their correct names and classification, and references to the associated literature.