Lots of big moths are coming out now it's rained. They're attracted to our house lights and sit on the outside windows demanding to be photographed and cataloged on Canberra Nature Map.
Yes, and they can be challenging to identify. Given the forewing patterns vary significantly within and between species, the usual approach is to rely on using antennae structure and colour, using the Moths of Victoria (Part 6) visual key to the Oxycanus (genus). Unfortunatlely Moths of Victoria say the status of O. lyelli is uncertain and needs more work. Using their key the male of Oxycanus dirempta and O. lyelli have a very similar antennae structure, but they differ only in colour: those of O. lyella are a dark brown, whereas O. dirempta are red-brown. I'm not 100% which species we have here, but I think the anetannae are as likely red-brown in colour rather than dark brown. If there is another way to distinguish O. dirempta and O. lyelli on visual grounds in the field, I'm open to suggestions.
Thanks for the detailed comments, ibaird. I was basing my id on the similarity to Oxycanus lyelli . The patterning is very similar as is the antennae colour, but perhaps it's possible that one was misidentified?