True bugs

Code QH999999

See Key to Families of Australian Aquatic Hemiptera (True-bugs)

Hemimetabolous insects, with about 4,000 aquatic and semi-aquatic (including marine) species in about 20 families worldwide, belonging to three heteropteran infraorders (Gerromorpha, Leptopodomorpha and Nepomorpha). Possessing subordinal characteristics of mouthparts modified as a rostrum (beak) and fore wings as hemelytra; spiraculate with various gaseous exchange mechanisms; nymphs with one, adults with two or more tarsal segments; antennae 3- to 5-segmented, inconspicuous in aquatic groups but obvious in semi-aquatic ones; often with reduction, loss and/or polymorphism of wings.

Nymphs with 5, rarely 4 instars, often univoltine. Gerromorphs (water-striders) scavenge or predatory on water surface; diving taxa are either predatory (eg. back-swimmers (Notonectidae) such as Notonecta , water-scorpions (Nepidae) such as Nepa , giant water bugs (Belostomatidae) or phytophagous detritivores (some water-boatmen (Corixidae) such as Corixa ).