Overview
The water-treaders or pondweed bugs are semi-aquatic and are commonly found on the surface of slow moving water, though some species are terrestrial or associated with wet rock faces or vegetation. The semi-aquatic species can be extremely agile. The Mesoveliidae are the only family included in the Mesovelioidea.
The Mesovelids are carnivorous, existing on a diet of small crustaceans such as ostracods and cladocerans, as well as other insects. Prey is usually captured using the rostrum, but then may be held in the front legs while the insect feeds. Some species have symbionts in the midgut, though the exact relationship between the organisms has yet to be determined.
The Mesoveliidae exhibit a high degree of variation in wing morphology. Some winged forms even shed their wings and absorb the wing muscles.
Eggs of the semi-aquatic species are laid in the tissues of plants.
Distribution
Mesoveliinae is the only subfamily found in Australia.
Austrovelia queenslandica
is the only representative of the genus
Austrovelia
, while the cosmopolitan genus
Mesovelia
contains 4 species.