Ant-lions: The spring and summer of 2002/2003 has been the driest for many years. In places, around Yallaroo, the soil is like powder. In some of these areas, conical pits have appeared in large numbers. They are about five centimetres in diameter and four centimetres deep (see image).Wildlife
The larvae of Lacewing insects dig these pits. The adults lay their eggs in loose, sandy soil often in sheltered situations. The larvae are known as Ant-lions for reasons soon to be revealed. The image on the left shows the larva. The body is about one centimetre long and the head is surmounted by a pair of fearsome jaws. The larva uses its body like a plough and flips out the soil as it digs the conical pit. When the pit depth meets requirements the Ant-lion hides at the bottom with only its jaws exposed. Foraging ants and other insects fall into the pit and as they try to escape the larva flips soil at them until they fall to the bottom. The hapless victim is held by the jaws, its juices are sucked out and the empty skin thrown away from the pit. As you can see Ant-lion is a very apt name.
When the larva matures it spins a cocoon covered in sand grains. Like butterflies and caterpillars, the appearance of the adult Lacewing and its larva bear no relationship to each other. The adults are delicate insects with large wings and are weak fliers. They are reputed to feed on aphids and other sap-sucking insects.
Lacewing larvae are able to inflict a bite. We have learnt this from painful experience.