How well-researched is that guidebook?
There ought to be *naphtho*quinones (and possibly glycosides thereof)
in _Nepenthes ampullaria_, but I have so far never heared anything of
*anthra*quinones. The presence of these in _Nepenthes_ would, however
be ***VERY*** interesting because of a possible parallel to
Polygonaceae to which Nepenthaceae are now thought to be somewhat
related (in fact it is the second closest relative after
Plumbaginaceae according to rbcL sequence analysis).
Please reconsult the book if you can find any reference to the source
of the contained information. In any case, please communicate a
complete citation of the book (incl. authors, publisher, year,
page number, ISBN) to me. Thank you very much in advance.
Take very good care
Kind regards
Jan