Overview
The creeping water bugs are found Australia-wide and are represented by 4 genera and approximately 9 species. The taxonomic limits of this family are in dispute. The Naucoridae is the only family included in the superfamily Naucoroidea.
The Naucorids are predacious upon other fresh-water invertebrates including other aquatic bugs such as the Corixidae. They seize their prey in their raptorial front legs before piercing them with their mouthparts and extracting the nutrients.
They occupy a variety of strata within the water bodies they inhabit and may be found swimming near the surface or crawling around in the substrate. Naucorids take up air through their abdomen, though some overseas species carry an air store around with them that extracts dissolved oxygen from the surrounding water.
Distribution
Compared to most other parts of the world the Australian fauna is poorly represented in this family of Heteroptera. Three subfamilies containing 4 genera and 9 species occur in Australia. The subfamily Aphelocheirinae, containing the single species
Aphelocheirus (Aphelocheirus) australicus
is found only in Nth Queensland. The subfamily Laccocorinae contains two species
Heleocoris (Heleocoris) nebulosis
and
Laccocoris nontandoni
which are absent from the Australian mainland but occur on Christmas Island.
The largest subfamily in Australia, the Naucorinae, is represented by the genus Naucoris and contains 6 species only one of which (
Naucoris congrex
) is found outside tropical northern Australia.