Ladybird (Steelblue) Halmus chalybeus
Species: H. chalybeus
Binomial name: Halmus chalybeus
Common Name: Steelblue Ladybird
The Steelblue Ladybird is a small (length 4mm) hemisphere shaped and is dark metallic blue in colour. When viewed from above the wing covers are a complete circle. It is native to eastern Australia. The Steelblue ladybird was introduced to New Zealand as a biological control for citrus insects pests from Australia in 1899 and 1905 for the control of black scale and blue gum scale. It also feeds on aphids, scale insects and other small insects and mites. Ladybird feeding on scale insects is often evident from the ragged edges of the scale covers which are lifted and eaten to gain access to the soft scale beneath.
When hunting for prey the encounter different species of ants hunting for the honey-dew from the aphids. The ladybird hard circular wing-covers protect them from those ants. They withdraw their legs and antenna under these wing-covers and the ants cannot attack them.