Gauna aegusalis has mostly smooth white lines across the forewing (Pyralis farinalis has a distinct dip in the pale post medial line - closer to termen) G. aegusalis has half fawn-grey half tan area between 2 white lines (P. f. mostly sandy/fawn with some tan suffusion). In G. aegusalis the basal section of the forewing extending to the first white line is fawn-grey (P. f. this section is tan) https://bold-au.hobern.net/specimens.php?taxid=9841 https://inaturalist.ala.org.au/observations?place_id=6744&quality_grade=research&taxon_id=380430