Exactly why I postulated that in the first place, Dorgon 500. There are numerous processes in nature that allow deposition of certain organic or inorganic molecules in different places of an organism for numerous reasons, and methinks it's a neat touch to inlcude that for the Bug Queen. And it works well too- none of the Main's team can hit the queen anywhere, but the unprotected and unshielded part of her, so she was near invincible in that respect.
It would be interesting to see if Craig decides to expand slightly the Bug enemy set (possibly including the suggestions aired here and elsewhere?) and see if that still fits in with the proposed theories.