Hi, Meursault, re bugs and beetles, I wonder whether the setter was thinking of the Volkswagen Beetle, which was known in the USA as the Volkswagen Bug (cf the movie "The Love Bug"). Although the dictionary definition of "bug" is fairly loose, it is, I agree, too much of a stretch to apply it to any insect.
I'm away from home for Christmas, but I made sure I packed my copy of The Chambers Dictionary, in its seasonal red dust-jacket.
A Happy Christmas to all contributors and "lurkers" on the Listener forum.