Abstract
The family
Microthyriaceae sensu
Lumbsch and Huhndorf 2010
is a poorly known but interesting family comprising 50 genera consisting of foliar epiphytes or saprobes on dead leaves and stems. We re-visited the family based on examinations of generic types where possible. Members are distributed in
Aulographaceae
,
Asterinaceae, Microthyriaceae, Micropeltidaceae
and
Palmulariaceae
and notes are provided on each of these families. Nine genera are transferred from
Microthyriaceae
to
Asterinaceae
, and two to
Aulographaceae
based on the splitting or dissolving nature of the thyriothecia to release ascospores. New sequence data for a number of species and genera are provided.
Microthyriaceous
members growing on other fungi and lichens differ from
Microthyriaceae sensu stricto
and the family
Trichothyriaceae
is reinstated to accommodate these taxa. Other genera of
Microthyriaceae
belong in
Rhytismataceae, Stictidaceae, Venturiales incertae cedis
,
Dothideomyetes
genera
incertae cedis, Hypocreales incertae cedis
and Ascomycota genera
incertae cedis
. The family
Microthyriaceae
is reduced to seven genera characterised by superficial, flattened thyriothecia, with the cells of the upper wall radiating in parallel arrangement from the distinct central ostiolar opening, while the lower peridium is generally poorly developed. Sequence data is provided for five species with thyriothecia and
Paramicrothyrium
and
Neomicrothyrium
are described as new genera and
Micropeltis zingiberacicola
is introduced as a new species. Our phylogenetic analysis underscores the high genetic diversity for thyriotheciate species and there is no clear clade that can be well defined as
Microthyriales
. Nuclear ribosomal data support multiple polyphyletic lineages within
Microthyriaceae
and
Micropeltidaceae
. Some unexpected DNA based phylogenetic relationships such as those between
Muyocopron
and
Saccardoella
will require corroboration with more complete taxon sampling as well as additional non ribosomal markers. There are few differences between
Aulographaceae
,
Asterinaceae
and
Palmulariaceae
and these families may need synonymising.