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

Abstract

The family Microthyriaceae is represented by relatively few mycelial cultures and DNA sequences; as a result, the taxonomy and classification of this group of organisms remain poorly understood. During the investigation of the diversity of aquatic hyphomycetes from southern China, several isolates were collected. These isolates were cultured and sequenced and a BLAST search of its LSU sequences against data in GenBank revealed that the closest related taxa are in the genus Microthyrium. Phylogenetic analyses, based on the combined sequence data from the internal transcribed spacers (ITS) and the large subunit (LSU), revealed that these isolates represent eight new taxa in Microthyriaceae, including two new genera, Antidactylariagen. nov. and Isthmomycesgen. nov. and six new species, Antidactylaria minifimbriatasp. nov., Isthmomyces oxysporussp. nov., I. dissimilissp. nov., I. macrosporussp. nov., Triscelophorus anisopterioideussp. nov. and T. sinensissp. nov. These new taxa are described, illustrated for their morphologies and compared with similar taxa. In addition, two new combinations are proposed in this family.

Micromicetos asexuales hallados sobre hojas de Quercus spp. (Fagaceae) en Huixquilucan, Estado de México, México

“…Tomando en cuenta que en las últimas décadas se han descrito una extraordinaria cantidad de especies de MA asociados a hojas de muy diferentes tipos de plantas (Delgado y Miller, 2017;Crous et al 2020;Qiao et al 2021), se piensa que la exploración taxonómica de las comunidades fúngicas asociadas a los restos vegetales puede aportar valiosa información al conocimiento global de la diversidad fúngica (Tennakoon et al, 2021). En particular para México, ante la gran diversidad de Quercus spp.…”

Novelties in Microthyriaceae (Microthyriales): Two New Asexual Genera with Three New Species from Freshwater Habitats in Guizhou Province, China

“…Hongsanan et al [ 12 ] added two new asexual genera and provided a holomorphic family description. Two new Triscelophorus species were introduced by Qiao et al [ 13 ], and the systematic placement of Triscelophorus was confirmed within Microthyriaceae. Recently, four asexual genera were introduced to the family [ 13 , 14 ].…”

“…Two new Triscelophorus species were introduced by Qiao et al [ 13 ], and the systematic placement of Triscelophorus was confirmed within Microthyriaceae. Recently, four asexual genera were introduced to the family [ 13 , 14 ]. So far, Microthyriaceae contains 16 genera, including eight asexual genera, Antidactylaria , Hamatispora , Isthmomyces , Keqinzhangia , Neoanungitea , Pseudocoronospora , Pseudopenidiella , and Triscelophorus [ 12 , 13 , 14 , 15 ].…”

“…Recently, four asexual genera were introduced to the family [ 13 , 14 ]. So far, Microthyriaceae contains 16 genera, including eight asexual genera, Antidactylaria , Hamatispora , Isthmomyces , Keqinzhangia , Neoanungitea , Pseudocoronospora , Pseudopenidiella , and Triscelophorus [ 12 , 13 , 14 , 15 ]. Asexual morphs in Microthyriaceae are characterized by micronematous to macronematous, mononematous, unbranched or branched, hyaline or brown conidiophores, some reduced to conidiogenous cells, integrated, terminal, determinate or sympodial, mono- to polyblastic conidiogenous cells, and subcylindrical to ellipsoid, obclavate, pale brown, verruculose, aseptate to multi-septate conidia, solitary or in branched chains, sometimes radial on compact heads; ramoconidia when present, subcylindrical to fusoid-ellipsoid, pale brown, verruculose, aseptate [ 12 ].…”

“…Asexual morphs in Microthyriaceae are characterized by micronematous to macronematous, mononematous, unbranched or branched, hyaline or brown conidiophores, some reduced to conidiogenous cells, integrated, terminal, determinate or sympodial, mono- to polyblastic conidiogenous cells, and subcylindrical to ellipsoid, obclavate, pale brown, verruculose, aseptate to multi-septate conidia, solitary or in branched chains, sometimes radial on compact heads; ramoconidia when present, subcylindrical to fusoid-ellipsoid, pale brown, verruculose, aseptate [ 12 ]. Sexual morphs in the family have circular, flattened, dark brown thyriothecia with radiating cells and a central ostiole, cylindrical to obpyriform, 8-spored asci and fusiform to ellipsoidal, hyaline or brown, 1-septate ascospores, often with ciliate appendages [ 4 , 8 , 12 , 13 , 14 , 15 , 16 ].…”