I do not know exactly how to reproduce this, as this is quite a large modpack I'm playing, but in both 1.0.0 and 1.1.0 versions of Arcane Twilight, when you die, a Totem of Holding from Quark Oddities should be produced. This does not happen if you are wearing a tamed beetle on your shoulder. I am unsure if items and experience will still drop if no deathchest-type mods are installed, but after trying other mods, such as Enigmatic Graves, I have found that, instead of any kind of deathchest being spawned upon death, all items and experience simply disappear immediately, leaving no chance for the player to retrieve any of them. No death message will show up in chat either. It does not seem to matter whether or not the beetle is nametagged.

That's a little odd, I'll look into it and see if I can work out what's going on.