Heliocephala variabilis and Pseudopenidiella vietnamensis: Two New Hyphomycetous Species in the Microthyriaceae (Dothideomycetes) from Vietnam

Abstract

In a survey of microfungi from plant debris collected in Vietnam, two new hyphomycetous species were found, which belong to the genera Heliocephala and Pseudopenidiella and the family Microthyriaceae (Microthyriales, Dothideomycetes). Maximum Likelihood and Bayesian Inference sequence analyses of the internal transcribed spacers (ITS) and large subunit (LSU) of the ribosomal DNA barcodes allowed assessing the phylogenetic relationships of the new species with other species of the respective genera. Heliocephala variabilis sp. nov. was closely related to Heliocephala elegans, Heliocephala gracilis, and Heliocephala zimbabweensis, from which it was morphologically distinguished by its smaller conidiophores and non-rostrate conidia of up to four septa on the natural substratum. Pseudopenidiella vietnamensis sp. nov. was related to Pseudopenidiella piceae and Pseudopenidiella podocarpi and differed from the former principally by its lack of microcondiophores and from P. podocarpi by having larger macroconidiophores and smooth conidia. Key morphological features to distinguish the accepted species in Heliocephala and Pseudopenidiella are also provided. In addition, Pseudopenidiella pini was excluded from the genus on the basis of its morphological features.

Two new asexual genera and six new asexual species in the family Microthyriaceae (Dothideomycetes, Ascomycota) from China

“…The genus is characterised by macronematous, mononematous, erect, straight or flexuous, sometimes sinuate, septate, unbranched or sparingly branched, hyaline, smooth conidiophores. The conidiogenous cells are monoblastic, sometimes sympodially extended, integrated, hyaline that produce a solitary, acrogenous, septate, staurospore composed of a main axis and 3 or more branches verticillate arranged from the basal cell of the main axis (Ingold 1943;Seifert et al 2011). Duarte et al (2015) found that Triscelophorus was polyphyletic, based on ITS analysis, but our phylogenetic analysis, based on two-loci and ITS, showed the genus should be monophyletic.…”

“…Triscelophorus Ingold was established with T. monosporus Ingold as type species; now, eight species have been accepted in this genus (Ingold 1943;Wijayawardene et al 2017). However, the positions of Triscelophorus in ordinal and familial levels are still unclear.…”

“…Preliminary searches with newly-generated LSU and ITS gene sequences of these isolates against National Center for Biotechnology Information ( NCBI ) by the Basic Local Alignment Search Tool ( BLAST ) determined species closely related to our isolates. Based on this information, sequences of ITS and LSU were downloaded from Microthyriaceae and four sister orders belonging to Dothideomycetes , including 48 strains representing 35 species (Table 1 ), according to recent studies ( Hongsanan et al 2020 ; Iturrieta-González et al 2020 ). Schismatomma decolorans (Erichsen) Clauzade & Vězda was used as the outgroup taxon.…”

“…Based on this information, sequences of ITS and LSU were downloaded from Microthyriaceae and four sister orders belonging to Dothideomycetes, including 48 strains representing 35 species (Table 1), according to recent studies (Hongsanan et al 2020;Iturrieta-González et al 2020). Schismatomma decolorans (Erichsen) Clauzade & Vězda was used as the outgroup taxon.…”

“…Notes. Triscelophorus was established by Ingold, with T. monosporus as type species (Ingold 1943). The genus is characterised by macronematous, mononematous, erect, straight or flexuous, sometimes sinuate, septate, unbranched or sparingly branched, hyaline, smooth conidiophores.…”