A comprehensive molecular phylogeny of <i>Cephalotrichum</i> and <i>Microascus</i> provides novel insights into their systematics and evolutionary history

Abstract

The genera <i>Cephalotrichum</i> and <i>Microascus</i> contain ecologically, morphologically and lifestyle diverse fungi in <i>Microascaceae</i> (<i>Microascales</i>, <i>Sordariomycetes</i>) with a world-wide distribution. Despite previous studies having elucidated that <i>Cephalotrichum</i> and <i>Microascus</i> are highly polyphyletic, the DNA phylogeny of many traditionally morphology-defined species is still poorly resolved, and a comprehensive taxonomic overview of the two genera is lacking. To resolve this issue, we integrate broad taxon sampling strategies and the most comprehensive multi-gene (ITS, LSU, <i>tef1</i> and <i>tub2</i>) datasets to date, with fossil calibrations to address the phylogenetic relationships and divergence times among major lineages of <i>Microascaceae</i>. Two previously recognised main clades, <i>Cephalotrichum</i> (24 species) and <i>Microascus</i> (49 species), were re-affirmed based on our phylogenetic analyses, as well as the phylogenetic position of 15 genera within <i>Microascaceae</i>. In this study, we provide an up-to-date overview on the taxonomy and phylogeny of species belonging to <i>Cephalotrichum</i> and <i>Microascus</i>, as well as detailed descriptions and illustrations of 21 species of which eight are newly described. Furthermore, the divergence time estimates indicate that the crown age of <i>Microascaceae</i> was around 210.37 Mya (95 % HPD: 177.18-246.96 Mya) in the Late Triassic, and that <i>Cephalotrichum</i> and <i>Microascus</i> began to diversify approximately 27.07 Mya (95 % HPD: 20.47-34.37 Mya) and 70.46 Mya (95 % HPD: 56.96-86.24 Mya), respectively. Our results also demonstrate that multigene sequence data coupled with broad taxon sampling can help elucidate previously unresolved clade relationships. <b>Citation</b>: Wei TP, Wu YM, Zhang X, et al. 2024. A comprehensive molecular phylogeny of Cephalotrichum and Microascus provides novel insights into their systematics and evolutionary history. Persoonia 52: 119-160. https://doi.org/10.3767/persoonia.2024.52.05 .