Multigene Molecular Phylogeny and Biogeographic Diversification of the Earth Tongue Fungi in the Genera Cudonia and Spathularia (Rhytismatales, Ascomycota)

Abstract

The family Cudoniaceae (Rhytismatales, Ascomycota) was erected to accommodate the “earth tongue fungi” in the genera Cudonia and Spathularia. There have been no recent taxonomic studies of these genera, and the evolutionary relationships within and among these fungi are largely unknown. Here we explore the molecular phylogenetic relationships within Cudonia and Spathularia using maximum likelihood and Bayesian inference analyses based on 111 collections from across the Northern Hemisphere. Phylogenies based on the combined data from ITS, nrLSU, rpb2 and tef-1α sequences support the monophyly of three main clades, the /flavida, /velutipes, and /cudonia clades. The genus Cudonia and the family Cudoniaceae are supported as monophyletic groups, while the genus Spathularia is not monophyletic. Although Cudoniaceae is monophyletic, our analyses agree with previous studies that this family is nested within the Rhytismataceae. Our phylogenetic analyses circumscribes 32 species-level clades, including the putative recognition of 23 undescribed phylogenetic species. Our molecular phylogeny also revealed an unexpectedly high species diversity of Cudonia and Spathularia in eastern Asia, with 16 (out of 21) species-level clades of Cudonia and 8 (out of 11) species-level clades of Spathularia. We estimate that the divergence time of the Cudoniaceae was in the Paleogene approximately 28 Million years ago (Mya) and that the ancestral area for this group of fungi was in Eastern Asia based on the current data. We hypothesize that the large-scale geological and climatic events in Oligocene (e.g. the global cooling and the uplift of the Tibetan plateau) may have triggered evolutionary radiations in this group of fungi in East Asia. This work provides a foundation for future studies on the phylogeny, diversity, and evolution of Cudonia and Spathularia and highlights the need for more molecular studies on collections from Europe and North America.

The genus Catathelasma (Catathelasmataceae, Basidiomycota) in China

“…PCR amplification was performed following Ge et al (2014) on an ABI 2720 Thermal Cycler (Applied Biosystems, Foster City, CA, USA). Primers used to amplify the internal transcribed spacer (ITS) region and the large subunit (LSU) of the ribosomal DNA and translation elongation factor 1-α (TEF1) were ITS1F/ITS4, LR0R/LR5 and 983F/1567R, respectively (Gardes and Bruns 1993;Matheny 2005;Rehner and Buckley 2005).…”

“…Primers used to amplify the internal transcribed spacer (ITS) region and the large subunit (LSU) of the ribosomal DNA and translation elongation factor 1-α (TEF1) were ITS1F/ITS4, LR0R/LR5 and 983F/1567R, respectively (Gardes and Bruns 1993;Matheny 2005;Rehner and Buckley 2005). Polymerase chain reaction (PCR) parameters follow those of Ge et al (2014). PCR products were purified using a QIAquick PCR purification kit (Qiagen Science, USA) and sent to Kunming Shuoqing Biotech Ltd. (Kunming, China) for sequencing.…”

Redescription of Clitocybe umbrinopurpurascens (Basidiomycota, Agaricales) and revision of Neohygrophorus and Pseudoomphalina

“…PCR reactions were performed on an ABI 2720 Thermal Cycler (Applied Biosystems, Foster City, CA, USA) using the published primer sets: ITS1F / ITS4 for the ITS region (Gardes & Bruns 1993), and LR0R / LR5 for the nucLSU region (Vilgalys & Hester 1990). PCR reaction parameters, sequencing reactions, and methods for editing the obtained sequences are the same as described in Ge et al (2014). The sequences produced in this study were deposited in GenBank and their accession numbers are indicated in Table 1.…”

A Taxonomic and Phylogenetic Investigation of Conifer Endophytes of Eastern Canada

“…Cudonia and Spathularia (Cudoniaceae, Rhytismatales) form a morphologically and ecologically divergent clade, producing relatively large (up to 10 cm tall) clavate to fan-shaped, capitate ascomata with sterile stipes and fertile apical regions. Despite these gross morphological differences, paraphyses, asci, and ascospores of Cudonia and Spathularia are typical of Rhytismataceae and the veil that covers the developing hymenium may be homologous to the covering layer of some Rhytismataceae species(Ge et al 2014). Molecular phylogenetic work shows Cudoniaceae is nested within, and therefore synonymous with, Rhytismataceae(Lantz et al 2011, Ge et al 2014).…”

“…Despite these gross morphological differences, paraphyses, asci, and ascospores of Cudonia and Spathularia are typical of Rhytismataceae and the veil that covers the developing hymenium may be homologous to the covering layer of some Rhytismataceae species(Ge et al 2014). Molecular phylogenetic work shows Cudoniaceae is nested within, and therefore synonymous with, Rhytismataceae(Lantz et al 2011, Ge et al 2014). This clade probably represents the transition from an endophytic or pathogenic life strategy to that of a saprotroph within Rhytismataceae.The genus Lophodermium (Rhytismataceae) comprises over 100 species predominately described from conifers(Kirk et al 2008) Larkin et al (2012).…”