Abantiades sp, possibly albofasciatus. Hepialid moths, also known as Ghost Moths and Swift Moths, are closely related to the Microlepidoptera, despite their huge size. They have tiny antennae, and the males gather and release pheromones to attract a mate - the reverse of the usual practice among moths.
This genus, found only in Australia, emerge from their burrows after rain. The caterpillers feed on Eucalyptus root, ringbarking the root and feeding on the subsequent tumour-like growth. They're also eaten as a prized bush food. The caterpillars are also quite prone to being parasitised and killed by Cordyceps fungus.
Fascinating pattern on the wings of these moths. This one turned up at a wedding north of Perth, a few years back