I don't think it is M. desmotoma. Can they really be so small? Also I see a difference in the pattern in side view. The white semicircle is missing and there is a small white spot instead.
I also thought the white semicurcle was missing but I couldn't find a match for it. This is the closest I found and the location is ok. https://bold-au.hobern.net/specimens.php?taxid=366701
I thought long and hard about this before plumping for M. desmotoma, but there aee doubts in my mind. The ragged boundaries to the white patches suggests M. euryleuca to me, but the greater extent of white on the head mitigatas against that species in my mind. It could be Dianne's suggestion of an unnamed ANIC Macrobathra (genus) but the diamond shaped white patch on the head of that species is different to this specimen. It's safely Macrobatha (genus) though i suppose.