Hi, Greg here.
My first post and pleased this topic has been raised, albeit initially 2 yrs ago. I'm setting up an aquaponics system, but am trying to grow the 'feed' myself. Yesterday I bought my first frozen 'bardi' (vardju?, aborigingal) to trial on my Murray cod. Unlike the central Aust grubs which infest the acacia roots, these eat River Red Gum (E. camaldulensis) roots on the Campaspe River where I live. All these grubs seem to be larvae of large moths. Mine, I think, are Trictena and Abantiades species.
The family of native beetles called Longicorns, also have an edible larvae which bore large holes into eucalypt species (my general observation), but seems less accessible
From my observations disecting this morning, Bardies/whitchetties are oily, and, importantly, guys, I think all of them have a parasitic worm inside. I extracted one entire hair-like 'worm', but until I receive my microscope and do a lot more reading, I can't definitively state they're worms, parasitic or otherwise. I'll happily eat anything. But these I'd only eat well cooked.
Sorry for the long initial post. I promise not to subject you to this again.