Macrogyrus striolatus Click to enlarge image
Whirligig Beetle, Macrogyrus striolatus Image: Andrew Donnelly
© Australian Museum

Fast Facts

  • Classification
    Species
    striolatus
    Genus
    Macrogyrus
    Family
    Gyrinidae
    Super Family
    Caraboidea
    Suborder
    Adephaga
    Order
    Coleoptera
    Class
    Insecta
    Subphylum
    Uniramia
    Phylum
    Arthopoda
    Kingdom
    Animalia
  • Size Range
    1.4 cm - 1.8 cm

The whirligig beetles, including Macrogyrus striolatus, are named after their habit of swimming in circles on water surfaces

Habitat

The Whirligig Beetle lives in freshwater.

Distribution

The Whirligig Beetle is found in eastern Australia.There are around 1,100 different species in the whirligig beetle group but relatively few of these (20) are found in Australia. About five species occur in the Sydney region.

Feeding and diet

Whirligig beetles feed by capturing and eating dead or injured insects on the water surface with their elongated front legs. The larvae are predators that crawl rather than swim. Like most predacious diving beetles, the adults find water by flying.

Other behaviours and adaptations

Whirligig beetles are among the most specialised beetles for living in and on water because all their legs are modified into flat paddles and their eyes are split to give both underwater and above-water vision. If a predator such as a bird approaches from above, the beetle dives below the water. If a predator such as a fish approaches from below, the beetle seeks shelter at the water's ed