May I introduce myself... My name is Arnoud Boom (23) and I am an
organic-chemistry student at the University of Amsterdam. I have just
joint the CP-list, and I saw some very interesting articles from some of
you about the evolution of CP's. I had just read some related information
about that, maybe it is interesting for some of you.
In the seventies some chemical substances have been isolated from several
Drosera species. Naphtoquinones anti-microbal activities and are probably
used to prevent extensive microbal growth on the caught insects.
Plumbagine and 7-methyljuglone are two naphtoquinones that are found in
Drocera species. It is very interesting to see that there is a certain
pattern in the distribution of the two around the world. It is clear that
of examined species, plumbagin occurs in all exclusively Australian
species. By the fact that Aldrovanda, Dionaea, and Drosophyllum also have
this plumbagin, we might assume that 7-methyljuglone is a more recent
develloped naphtoquinone than plumbagin. Since the Drosera's of the
Australian continent all have plumbagin, this might be some proof that the
Drosereae indeed originated from this area.
distribution of naphtoquinones.
Drosera:
Subg. Rorella DC. sect. Stelogyne DIELS.
D.hamiltonii 7-methyljuglone
Subg. Rorella DC. sect. Bryastrum PLANCH.
D.pygmaea plumbagin
Subg. Rorella DC. sect. Arachnopus PLANCH.
D.glanduligera plumbagin
Subg. Rorella DC. sect. Rossolis PLANCH.
D.intermedia plumbagin
D.rotundifolia 7-methyljuglone
D.anglica 7-methyljuglone
D.capilaris plumbagin
D.burkeana 7-methyljuglone
D.madagascariensis 7-methyljuglone
D.cuneifolia 7-methyljuglone
D.trinervia 7-methyljuglone
D.dielsiana 7-methyljuglone
D.capensis 7-methyljuglone & plumbagin
D.ramentacea 7-methyljuglone
D.spatulata 7-methyljuglone
Subg. Rorella DC. sect. Phycopsis PLANCH.
D.binata plumbagin
D.dichotoma plumbagin
Subg. Rorella DC. sect. Ptycnostigma DIELS.
D.cistiflora 7-methyljuglone & plumbagin
Subg. Ergaleium DC. sect. Polypeltes DIELS.
D.peltata plumbagin
D.auriculata plumbagin
D.microphylla plumbagin
Subg. Ergaleium DC. sect. Erythrorhiza PLANCH.
D.erythroriza plumbagin
D.whittakeri plumbagin
Subg. Ergaleium DC. sect. Stolonifera DE BUHR
D.stolonifera plumbagin
Distribution of plumbagin in other genera and thus closely related to
Droceraceae
Aldrovanda vesiculosa L. plumbagin
Dionaea muscipula Ell. plumbagin
Drosophyllum lusitanicum Link. plumbagin
No naphtoquinones in Drosera look-alikes, so not closely related to Droseraceae
Byblis gigantea Lindl. none
Roridula gorgonias PLANCH. none
Two very interesting examples are D.cistiflora and D.capensis, for they
have both naphtoquinoses. They might offer us an important clue about the
evolution of the Drosera's.
I hope that this has not been discussed before, butsince I've just joined
the CP-list I could not have known....
Kind Regards
Arnoud