Biologa

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FUNGI AND THEIR ALLIES
MEREDITH BLACKWELL AND JOSEPH W. SPATAFORA
A BROAD VIEW OF EUKARYOTES 8 KINGDOM FUNGI 9 PHYLUM CHYTRIDIOMYCOTA (ZOOSPORIC FUNGI) 10 PHYLUM ZYGOMYCOTA 11 CLADE GLOMALES 12 PHYLUM ASCOMYCOTA 12 Class Archiascomycetes 12 Class Saccharomycetes 13 Class Euascomycetes 13 PHYLUM BASIDIOMYCOTA 15 Class Ustilaginiomycetes 16 Class Urediniomycetes 16 Class Hymenomycetes 17 KINGDOM STRAMINIPILA (HETEROKONT ZOOSPORIC ORGANISMS) 18 Oomycota 19 Hyphochytriomycetes 19 Labyrinthulales and Thraustochytriales (and Aplanochytrium) 20 SLIME MOLDS 20 Plasmodiophorales (Parasitic Slime Molds) 20 Myxomycetes, Protostelids, and Dictyostelids (Plasmodial and Cellular Slime Molds) 20 Acrasid Slime Molds 20 CONCLUSIONS 20

Fungi are heterotrophic organisms that permeate our environment. With few exceptions fungi have filamentous bodies enclosed by cell walls, are nonmotile, and reproduce both sexually and asexually by spores. During the last decade, mycologists have made unprecedented progress toward producing a phylogenetic classification of fungi; a skeleton phylogeny based on analyses of DNA characters was developed relatively early on (Bruns et al. 1991; Alexopoulos et al. 1996; McLaughlin et al. 2001). Such a phylogeny serves as a basis on which hypotheses of fungal evolution can be developed. One important finding has been that “fungi” are polyphyletic (Table 1.1); their morphologies are convergent, having been derived independently from among several independent eukaryotic lineages (Fig. 1.1). A monophyletic group, exclusive of slime molds and oomycetes, is well defined and supported as “true fungi,” a kingdom-level taxon (Barr 1992; Bruns et al. 1993; Baldauf et al. 2000; Keeling et al. 2000). Historically fungi have been compared with plants and included in the study of botany. Contemporary studies, however, indicate that members of Kingdom Fungi are most closely related to animals, not plants, possibly through a choanoflagellate-like ancestor (Barr 1992;