Excuse me. I thought you were a Ladybird
A combination of warming weather and fresh young eucalyptus leaves means the Eucalyptus Leaf Beetles (Chrysomelidae family) are not far away. These often highly coloured beetles are sometimes called Tortoise Beetles and are often mistaken for Ladybird Beetles because of their shape (pictured below). For those whose livelihood is growing plantation eucalypts the Tortoise Beetle is a pest as both the larvae and the adults eat foliage over a long period in the year.
The adults over-winter under bark or mulch and come out in late spring/early summer to mate. Eggs are laid on the young eucalypt leaves and the hatched larvae as a group consume the entire leaf before moving on to the next. Disturbing them produces a reaction similar to that of spitfires, the abdomen gets raised and a mixture of hydrogen cyanide and eucalyptus oil is emitted (pictured below left). Two generations of beetles can be produced each season.
The larvae prefer young leaves whilst the adults eat older leaves, leaving the characteristic half-moon shapes on the leaf margins.
Eucalyptus Leaf Beetles are small (larger than a Ladybird) and very common. You will inevitably find them if you look carefully at your gum trees this summer. They will be either eating or mating or in some cases the female will eat whilst the male mates (pictured right).
What a way to spend the summer.
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