Molecular phylogeny reveals a core clade of Rhytismatales

Abstract

Rhytismatales (Leotiomycetes, Pezizomycotina, Ascomycota) are an order of mostly plantassociated ascomycetes with a global distribution. Well known taxa include the Rhytisma tar spots on Acer spp. and several needle-cast pathogens in genera Lophodermium and Meloderma. Critical studies are lacking at all taxonomic ranks from order to species, and in particular the genus taxonomy in the order has been criticized for being unnatural. We used nuclear LSU and mitochondrial SSU sequences in Bayesian phylogenetic analyses to define a core clade of Rhytismatales sensu stricto. Some of the genera traditionally placed within the Rhytismatales, Ascodichaena, Marthamyces, Mellitiosporium, Potebniamyces, Propolis and Pseudophacidium, are shown to be phylogenetically distinct, all related to various other taxa at present placed in the polyphyletic Helotiales. Within the core clade only Cudonia, Spathularia and Terriera are supported as monophyletic. The large genera Coccomyces, Hypoderma and Lophodermium all are polyphyletic as are a few smaller genera. The traditionally used characters of ascoma and spore shape are shown to be unreliable for the delimitation of monophyletic genera but in some cases can be useful when combined with other characters. In this study we provide 72 new nrLSU and 64 new mtSSU sequences. Together with publicly available sequences data for 103 specimens representing 91 species of Rhytismatales are now available. Despite this taxon sampling intensity is still too low to propose an alternative generic taxonomy.

Double‐digest RADseq loci using standard Illumina indexes improve deep and shallow phylogenetic resolution of Lophodermium, a widespread fungal endophyte of pine needles

“…Lophodermium (Chevall.) is a paraphyletic genus with over 100 named species that associate with dead or living plants worldwide (Lantz, Johnston, Park, & Minter, 2011). Those species associated with pine needles consist of a smaller (ca.…”

Placement of the genusAngelinawithin Rhytismatales and observations ofAngelina rufescens

“…gov/) BLAST query of the LSU and mtSSU rDNA region determined that A. rufescens was most similar to genera in the Rhytismatales. LSU and mtSSU rDNA sequences from 69 taxa representing members of the Rhytismatales sensu stricto (Lantz et al 2011) were included in a combined phylogenetic analyses of the LSU and mtSSU rDNA region. Phacidium lacerum, Lachnum bicolor and Pezicula carpinea were used as outgroup taxa.…”

“…Phacidium lacerum, Lachnum bicolor and Pezicula carpinea were used as outgroup taxa. These taxa and their GenBank accession numbers are in Lantz et al (2011).…”

“…The combined LSU and MtSSU DNA alignment is available from TreeBase under S14647. Regions of the DNA sequences that were highly divergent, as described by Lantz et al (2011), were not included in the analysis and resulted in a dataset of 1804 base pairs. DNA sequence alignments were analyzed as described by LoBuglio and Pfister (2010) with: MrBayes 3.0b4 (Ronquist and Heulsenbeck 2003) for obtaining Bayesian posterior probabilities (PP); maximum parsimony (MP) with PAUP 4.0b10 (Swofford 2002); and maximum likelihood (ML) with RAxML-HPC2 on Abe through the Cipres Science Gateway (Miller et al 2009).…”

“…He referred us to a classic paper on this species by Durand (1902), which Korf also cited in his treatment of discomycetes (Korf 1973). Subsequent morphological and sequence analyses resolved the placement of this genus not in the Dermateaceae, where Durand (1902) and Korf (1973) had placed it, but instead among the core clade of Rhytismatales (Lantz et al 2011). …”