untitled

Fig. 2.6(A,B) Fossil hyphae and spores from the Ordovician, about 460 mya, compared with a spore (C) of a present-

day Glomusspecies (an arbuscular mycorrhizal fungus). All scale bars = 50 mm. (Images courtesy of Dirk Redecker; see

Redecker et al. 2000.)

Fig. 2.5Vesicles (v) and arbuscules

(a) of present-day arbuscular mycor-

rhizal fungi in clover roots.

Diversisporaceae fam. ined.

Gigasporaceae

Glomeraceae

(Glomus-group A)

Glomeraceae

(Glomus-group B)

Basidiomycetes

and ascomycetes

Glomerales

Diversisporales

Acaulosporaceae

(^8984)
Paraglomerales
Paraglomeraceae
Archaeosporales
Archaeosporaceae
Geosiphonaceae
Fig. 2.4Proposed generalized taxonomic structure of the AM fungi and related fungi (Glomeromycota). Thick lines
delineate “bootstrap” values (indicating relatedness between the main branches) above 95%. Lower values (89% and
84%) are shown on two of the branches. (Reproduced by courtesy of Schuessler et al. 2001, and the British Mycological
Society.)
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