Introduction to Fungi, Third Edition

TAXONOMY OF FUNGI
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Fig1.26 Phylogenetic relationships within the Eumycota, based on18S rDNA comparisons.This tree illustrates the analytical
power of molecular phylogenetic analyses; all four phyla of Eumycota are resolved. However, it also highlights problems in that
Basidiobolus groups with the Chytridiomycota, although sharing essential biological features with the Zygomycota, and that
conversely Blastocladiella groups with the Zygomycota instead of the Chytridiomycota. Modified and redrawn from Berbee and
Taylor (2001), with kind permission of Springer Science and Business media.
with glomalean members of the Zygomycota
(see p. 218).
1.5.4 The taxonomic system adopted
in this book
The discipline of fungal taxonomy is evolving at
an unprecedented speed at present due mainly
to the contributions of molecular phylogeny.
Numerous taxonomic systems exist, but this is
not the place to discuss their relative merits
(see Whittaker, 1969; Margulis et al., 1990;
Alexopoulos et al., 1996; Cavalier-Smith, 2001;
Kirk et al., 2001). In this book we have tried to
follow the classification proposed in The Mycota
Volumes VIIA and VIIB (McLaughlin et al., 2001),
but even in these volumes the authors of
different chapters have used their own favoured
systems of classification rather than adopting
an imposed one. In cases of doubt, we have
attempted to let clarity prevail over pedantry.
Fungi in the widest sense, as organisms
traditionally studied by mycologists, currently
fall into three kingdoms of Eukaryota, i.e. the
Eumycota which contain only fungi, and the
Protozoa and Chromista (¼ Straminipila), both
of which contain mainly organisms not studied
by mycologists and were formerly lumped
together under the name Protoctista (Beakes,
1998; Kirk et al., 2001). The Protozoa are
notoriously difficult to resolve by phylogenetic
means, and the only firm statement which can
be made at present is that they are a diverse
and ancient group somewhere between the
higher Eukaryota (‘crown eukaryotes’) and the