Very large order with 119 families, containing over 6,000 species found in Australia. Split into four suborders, largest being Heteroptera with 67 families in Australia, followed by Sternorrhyncha with 29 families, then Auchenorrhyncha with 21 families and Coleorrhyncha, which contains a single family. Extremely variable in both size (1 to 110mm) and colour, with some species among the most brightly coloured and spectacularly patterned of all insects. Wings, if present, cross over when at rest, and wingless species typically live under protective coverings. All species have sucking, tubelike mouthparts. Some families can be direct pests of humans, such as bed bugs, which are external parasites of humans, typically within crowded situations and residences with poor hygiene, and assassin bugs, which can carry disease-causing pathogens. Others, such as aphids, are pests of crops and flower gardens.