Group of shield bugs spotted at Long Point

They are rather similar in shape, and most of them smell strongly when crushed.

The orange and black garden pest known as the harlequin bug is the best-known local example.

Today's photo shows a group of shield bugs - cherry ballart shield bugs - so named because both the young ones and the adults feed on the foliage of the cherry ballart or wild cherry tree. The V-shaped mark on the abdomen is distinctive. This cluster of handsome bugs was discovered under bark, where they had no doubt been sheltering over winter. Harlequin bugs have the same habit of clustering together in the colder months and dispersing when the weather becomes warmer.

The photo was taken at Long Point, west of Creswick, where there are cherry ballart trees that will provide food. Ballarts are densely foliaged, bright green cypress-like trees found scattered through local forests.

The word "bug" is frequently misused for any small insect. Those in the photo belong to the insect order known as "true bugs", which feed by sucking sap from plants. Beetles are in a different order of insects. Most beetles are chewers rather than suckers.

Like those of harlequin bugs - and most other true bugs - the young ones of these shield bugs look different from the adults. The abdomen is orange with a black central spot. They grow by stages until they reach adult size and colour, whereas beetles have a grub stage that pupates into the adult beetle.

Although not seen frequently in the Ballarat district, these shield bugs are widespread throughout most of south-eastern Australia.

Long Point Flora Reserve is a small nature reserve with a number of interesting plant species. It is best-known for its silver banksia, yellow box and candlebark trees, but there are many small plants as well, including parrot peas, pink bells, trigger plants and beard heath. Wildflowers are at their best later in spring.

SHELDUCKS

Our largest local duck is the Australian shelduck, prominent because of its orange breast.

Pairs of shelducks (sometimes known as mountain ducks) have been seen in paddocks in many places for a couple of months; the male standing upright and alert, with his darker-breasted mate alongside or not far away.

While some shelducks remain paired up in paddocks, a few have already produced their broods of ducklings. One brood of a dozen new ducklings was spotted at Navigators a week ago.

NATURE QUERIES ANSWERED

Can you identify this caterpillar, found beneath a gum and a wattle tree on a fence?

Nature Lover, Ballarat Central.

This is a caterpillar of the lemon gum moth, distinctive among green Australian caterpillars because it has an unusual horn on its head.

Other green caterpillars, such as those of the hawk moths, have a horn at the rear. The horn is rather soft, moving somewhat as the caterpillar moves along.

The head is red, and the caterpillar reaches a maximum size of around 35mm before it pupates. There is a pale line along its back and its tail is pointed, rather than rounded or blunt.

This caterpillar turns into a rather plain fawn moth, sometimes tinged yellow. The moths appear in autumn.

• Questions and photos are welcome. Email to rthomas@vic.australis.com.au, or send to Roger Thomas at The Courier, PO Box 21, Ballarat, 3353.