Hi Miranda, I dont think this is Castiarina interstitialis which it either is, or is a separate species similar thereto. It looks like one of the specimens of this (whatever it is) that were photographed in the same general area last season, and deserves closer inspection, especially males if possible as the genitalia can be (though not always) diagnostic to species level. A couple of specimens have recently been set aside for me to investigate, but are you able to grab a few for me as well please? The longer the seies I can look at the better I can decide what is going on. Cheers, Allen (contact me via Facebook or Facebook Messenger if possible please. Sadly, NatureMappr is closing soon).
Hi Allan @entom2, I hear Stuart got you some specimens and they probably are interstitialis. I doubt I will be back out there this season but if I am I will make sure to collect some if I see them again. Cheers!