Wilt thou suck?

The recent summer rains seem to have kick started, or at the very least prolonged, the growth of young eucalypt leaves in the local gum trees. For small trees it is easy to get a good look at them. On some of the trees the tips of the new leaves appear to have been wilted and dried, see picture left.

If you carefully examine the trees thus afflicted you will probably find the presence of small brown insects (see photo below). These insects unsurprisingly are known as Eucalyptus Tip-wilter Bugs (Amorbus sp.). They are of the Order Hemiptera meaning that they have sucking mouthparts. Both the adults and the young (known as instars) suck the sap out of the newly developed leaves leaving them dry and shriveled. An infestation of bugs will not kill a tree but could severely stunt its growth.

The adults are brown in colour and have wings. They usually hang upside down camouflaged among the wilted tips. The male (pictured) has ‘fat thighs’ on the back pair of legs. The female bug does not. The bug develops through a number of moulting stages. The instars at each stage are wingless, although wing buds can be seen, and highly coloured (see picture right). The colour and the pattern define which instar stage it is.

If nothing else, you can see that adult bugs have had a colourful past.