Introduction to Fungi, Third Edition

AERO-AQUATIC FUNGI
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means of dispersal are the carriage of wind-borne
ascospores and basidiospores of the teleomorphs,
passive dispersal of conidia by waterfowl, and
conidium dispersal at the water surface during
flooding.
Aero-aquatic fungi show some host specificity.
Leaves and twigs of broad-leaved trees are
colonized by a wide range of species, but leaves
of coniferous needles such as Pinus have a more
restricted mycota including Hd. fractum and
Hd. hyalinum. Monocotyledonous hosts such as
grasses, rushes and sedges support few species,
but exceptions are Hd. praetermissum, Spirosphaera
carici-graminis and S. minuta. Fruiting of Aegerita
and Aegeritina is supported on woody substrates
rather than leaves, whereas Pseudaegerita spp.
fruit both on rotten wood and on leaves. There
are also differences in frequency in relation to
water chemistry (Voglmayr, 2000). For example
B. pulmonaria, Hd. conglomeratum, Hd. tubulosum
and Helicoon fuscosporum are found in eutrophic
waters, Spirosphaera minuta is characteristic
of oligotrophic conditions, and Candelabrum
desmidiaceum is mostly found in dystrophic
conditions. Other species have a wider tolerance.
Helicodendron triglitziense and S. floriformis are
two very common species found in dystrophic
to eutrophic waters.
Like so many fungi described in this book,
aero-aquatic species have adopted, by convergent
evolution, a suite of flexible characters which
has enabled them to explore a habitat of
extremes, in this case the amphibious environment
involving changes between anaerobic and
aerobic conditions, and between aquatic and
terrestrial lifestyles.