Abstract:
The order Phyllachorales (Pezizomycotina, Ascomycota) is a group of biotrophic, obligate plant parasitic
fungi with a tropical distribution and high host specificity. Traditionally two families are recognised within this order:
Phyllachoraceae and Phaeochoraceae, based mostly on morphological and host characteristics. Currently, the
position of the order within the class Sordariomycetes is inconclusive, as well as the monophyly of the order, and
its internal phylogenetic structure. Here we present a phylogeny of the order Phyllachorales based on sequence
data of 29 species with a broad host range resulting from a wide geographical sampling. We inferred Maximum
Likelihood and Bayesian phylogenies from data of five DNA regions: nrLSU rDNA, nrSSU rDNA, ITS rDNA, and
the protein coding genes RPB2, and TEF1. We found that the order Phyllachorales is monophyletic and related
to members of the subclass Sordariomycetidae within Sordariomycetes. Within the order, members of the family
Phaeochoraceae form a monophyletic group, and the family Phyllachoraceae is split into two lineages. Maximum
Likelihood ancestral state reconstructions indicate that the ancestor of Phyllachorales had a monocotyledonous
host plant, immersed perithecia, and a black stroma. Alternative states of these characters evolved multiple times
independently within the order. Based on our results we redefine the family Phyllachoraceae and propose the new
family Telimenaceae with Telimena erythrinae as type species, resulting in three families in the order. Species of
Telimena spp. occur in several monocotyledonous and eudicotyledonous host plants except Poaceae, and generally
have enlarged black pseudostroma around the perithecia, a character not present in species of Phyllachoraceae.
