The Geography of Phytochemical Races

Chapter 5
Wide Disjunctions
This chapter presents examples of taxa that enjoy very wide distributions that may involve
several continents or, in the case of marine algae, several oceans. In addition to the algae,
examples include higher plants, lichens, and bryophytes. Owing to the extensive literature
involving chemistry of marine algae, the examples included represent only a sample.
We begin with some widespread examples from the vascular plant chemical literature.
5.1 Vascular Plants
5.1.1 Coriariaceae
Coriaria is the sole genus in Coriariaceae, a family that enjoys a wide and interesting
distribution, including China, Japan, Taiwan, Tibet, New Zealand, and Mexico. Several
questions surround an understanding of this little family, including its size, its phylogenetic
position in the angiosperm scheme of things, and how it has come to occupy the
places where it can now be found. Flavonoids of 12 species of Coriaria were studied
as a possible aid to the problem of ordinal affi nities of the family (Bohm and Ornduff,
1981). Plants examined in that study represented much of the range of the genus as
noted above. The pigment profi le, which consisted of common kaempferol and quercetin
mono- and diglycosides and a common fl avanonenaringenin 7-O-glucoside, was
largely homogeneous among the species. Flavonoid data offered no insights into relationships,
including the three groups defi ned by Good (1930) based upon fl oral presentation.
Recent information on ordinal relationships of Coriariaceae based on DNA
sequence information can be found in a paper by Wagstaff and Dawson (2000).
5.1.2 Gentianaceae
The following example comes from the work of Gottlieb and Kubitzki (1983) on
the use of xanthones as indicators of relationships within Gentianaceae, a family
B.A. Bohm, The Geography of Phytochemical Races,
© Springer Science+Business Media B.V. 2009
217