Don, sorry, no, even if I could go back to the location it is very unlikely that it would be sitting there on the same flower, supposing that I was even able to find the same flower again.
OK, noted, But see sighting no. 4404812 which was previously identified as Psychidae genus (immature). Are we sure this/these and similar observations are all H. argyroleuca or similar? See also sighting No 4403241 (on native lily sp.).
The original larvae identified as H argyroleuca were apparently feeding on flowers, and had cases decorated with flower petals. Then we had photos with larvae, with cases, feeding on flowers, but with cases covered in debris much like Hyalarcta huebneri or young Metura elongatus, so these were classified as Psychidae. This is the first sighting of a larva itself, feeding on a flower, with a debris covered case, with the larva identifiable as a Heliocosma. So yes, we have evidence now that the feeding on flowers rather than the decoration of the case is diagnostic of a Heliocosma species, and we should reclassify previous sightings accordingly.