Additions to the Xylariomycetidae (Sordariomycetes) Fungal Flora from Northern Thailand: Amphisphaeria chiangmaiensis sp. nov. and A. hydei sp. nov.

During the continuous investigation into inconspicuous xylarialean species in northern Thailand, two amphisphaeria-like taxa were found in samples collected between July and October 2022. Both taxa have solitary, immersed ascomata with a two-layered peridium and unitunicate asci that are morphologically similar to Amphisphaeria species. Macro-micro morphological comparisons with related taxa and multigene phylogenetic analyses based on combined internal transcribed spacer (ITS), partial 28S large subunit rDNA (LSU), partial RNA polymerase II second largest subunit (rpb2), and partial beta-tubulin (tub2) sequences revealed that the two taxa are novel to science. Amphisphaeria chiangmaiensis sp. nov. is distinguished from known taxa by having larger ascomata, a J- apical ring in Melzer's reagent, and hyaline ascospores. Amphisphaeria hydei sp. nov. differs from its sister taxa in having larger ascomata, a longer ostiolar canal, and longer asci. Morphological descriptions, illustrations, and phylogenetic analyses of two novel taxa are provided herein.