There are over 5,000 species of ladybirds world-wide and more than 500 species which occur here in Australia!

Most Australian ladybirds eat scale insects and aphids – and help control these insect pests in gardens. The most common ladybird in the Canberra area is probably the spotted ladybird, Harmonia conformis. The Botanic Gardens in Canberra uses ladybirds to help control insect pests in its glasshouses. Most Australian ladybirds live under the bark of eucalypt trees and eat scale insects. Ladybirds can be tiny, some species are only 2mm in diameter. Not all ladybirds have spots, many species are plain black or brown. Male ladybirds and usually smaller then females. Ladybirds taste terrible – they produce a chemical which makes them unpleasant for birds and other predators to eat. Female ladybirds can produce over 100 eggs over their life. Some people have used crushed ladybirds to stop toothache – yuk! Australian ladybirds were the first biological control agents! The vedalia ladybird, Rodolia cardinalis, was sent to the USA in 1888 to control cottony cushion scale insects in citrus orchards. In Europe in the past ladybirds were thought to be able to predict the weather, if they fell off your hand it would rain, if they flew away it would be fine.

Spiders (order Araneae) are air-breathing chelicerate arthropods that have eight legs, and chelicerae modified into fangs that inject venom. In their bodies the usual arthropod segments are fused into two tagmata, the cephalothorax and abdomen, joined by a small, cylindrical pedicel. In all except the most primitive group, the Mesothelae, spiders have the most centralized nervous systems of all arthropods, as all their ganglia are fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure.

Scorpions are any arachnid of the order Scorpionida. They are members of the order Scorpiones within the class Arachnida. There are about 2,000 species of scorpions, found widely distributed south of about 49° N, except New Zealand and Antarctica. The northernmost part of the world where scorpions live in the wild is Sheerness on the Isle of Sheppey in the UK, where a small colony of Euscorpius flavicaudis has been resident since the 1860s.

Centipedes (from Latin prefix centi-, "hundred", and Latin pes,pedis, "foot") are arthropods belonging to the class Chilopoda and the Subphylum Myriapoda. They are elongated metameric animals with one pair of legs per body segment. A key trait uniting this group is a pair of venom claws or forcipules formed from a modified first appendage. This also means that centipedes are an exclusively predatory taxon, which is uncommon. Their bites may have effects ranging from mild discomfort to life threatening.