Data from: Taxonomy and phylogeny of the epiphytic sooty molds in family Metacapnodiaceae (class Eurotiomycetes, subclass Chaetothyriomycetidae)

<b>Abstract</b><br/><p><em>Metacapnodiaceae</em> is one of several sooty mold families in <em>Ascomycota</em>. With the goal of better characterizing species diversity, we determined complete or partial DNA sequence barcodes for ribosomal internal transcribed spacer (ITS) regions for 16 collections of <em>Metacapnodium</em> using a <em>Metacapnodium</em>-specific primer, followed by phylogenetic and morphological analyses. Tapering, moniliform hyphae, cells wider than long, and a distinctive phialidic asexual state were good predictors of membership in a well-supported <em>Metacapnodium</em> clade. Sequences from the 16 collections represent 9 named species of <em>Metacapnodium</em>. Barcoded species include: <em>M. stanhughesii</em> <strong>sp. nov.</strong>, <em>M. vancouverensi</em>s, <strong>sp. nov.,</strong> and <em>M. australis</em> <strong>comb. nov.</strong> Based on morphological characters, we propose <em>M. atro-olivaceus</em> <strong>comb. nov.</strong>, <em>M. novae-zelandiae</em> <strong>comb. nov.</strong>, and <em>M. pacificus</em> <strong>comb. nov.</strong> We provide a key to the identification of 15 species studied. To investigate the deeper phylogenetic relationships of <em>Metacapnodiaceae</em>, we sequenced partial nuclear ribosomal large subunit (LSU) gene regions from five specimens and elongation factor 1-alpha (<em>ef1-α</em>) gene regions from two specimens. In our analysis of concatenated sequences from ribosomal DNA, <em>ef1-a</em>, and from <em>rpb2</em>, the gene encoding the 2nd largest subunit of RNA polymerase II protein, <em>Metacapnodium</em> appeared within the subclass <em>Chaetothyriomycetidae</em>, class <em>Eurotiomycetes with strong support, and</em> as the sister group to <em>Pleostigmataceae</em> but without strong statistical support. Our study adds <em>Metacapnodiaceae</em> to the clades of enigmatic, slow-growing fungi of harsh environments with lichenized, lichenicolous, resinicolous, and rock-inhabiting niches. Resolving family relationships is relevant to age estimates of Ascomycota, as fossilized <em>Metacapnodium</em> specimens in amber potentially contribute to the calibration of divergence times.</p>