During a survey of saprobic microfungi in Southwest China, a coelomycetous fungus was found on dead twigs of Jasminum nudiflorum in Kunming, Yunnan Province. Based on a detailed morphological characterization coupled with multi-locus phylogenetic analyses, the fungus was identified as a new species in the genus Dothidea. Phylogenetic analyses using a combined matrix consisting of internal transcribed spacer (ITS), large subunit rRNA (LSU), small subunit rRNA (SSU), beta tubulin (tub2) and translation elongation factor-1 alpha (tef1-α) confirmed its placement in Dothideaceae and revealed a sister relationship to Dothidea eucalypti. The new species is characterized by pycnidial conidiomata, ampulliform or doliiform conidiogenous cells as well as aseptate, subglobose to ovoid, hyaline to pale-brown conidia. Comprehensive descriptions and illustrations are provided. Morphological characteristics of asexual morph taxa in Dothideaceae are also summarized and discussed.
Tag: anamorphs
Biphasic taxonomic approaches for generic relatedness and phylogenetic relationships of Teichosporaceae
The placement of the dothideomycetous family Teichosporaceae has been controversial. Recent phylogenetic investigations have used a taxonomic lumping approach with the Floricolaceae and its genera have been synonymized under the earlier family name, Teichosporaceae. Intergeneric relationships were therefore obscure and proper generic delimitation was needed in upcoming studies. We here taxonomically revised the family Teichosporaceae based on both morphological and phylogenetic evidence. Teichosporaceae species have immersed or semi-immersed, erumpent to superficial, ostiolate ascomata, cellular or trabeculate pseudoparaphyses, cylindrical to oblong or sub-clavate asci and ellipsoid to oblong or fusiform, cylindric-fusiform or oblong to elliptical, ovoid to clavate, symmetric or asymmetric, initially hyaline or pale brown to dark brown or yellowish brown, 1–3-septate or muriform ascospores. Asexual morphs are coelomycetous. Type or representative specimens of Teichosporaceae were loaned and fresh specimens were collected from China and Thailand. Maximum likelihood and Bayesian analyses of a combined ITS, LSU, SSU, tef1-α and rpb2 dataset were performed to clarify the phylogenetic affinities of taxa and examine monophyly of newly proposed genera. One new species (Floricola festucae), one new host record (Ramusculicola thailandica) and four new combinations (Aurantiascoma nephelii, A. quercus, Magnibotryascoma acaciae, M. melanommoides) are introduced. The broad genus concept of Teichospora is dismissed based on morphological dissimilarities and the monophyletic status of the proposed genera. We accept Asymmetrispora, Aurantiascoma, Floricola, Magnibotryascoma, Misturatosphaeria, Pseudoaurantiascoma, Pseudomisturatosphaeria, Ramusculicola and Teichospora as distinct genera in the Teichosporaceae. All recognized genera are phenotypically characterized and phylogenetically well-supported. The phylogenetic placements of three genera (Chaetomastia, Loculohypoxylon and Sinodidymella), which do not have molecular data cannot be conclusively clarified at present, but are still placed in Teichosporaceae for future studies.
Koorchaloma oryzae sp. nov. (Stachybotryaceae, Sordariomycetes), from Oryza sativa (Poaceae) in northern Thailand
A new species of Koorchaloma is described based on morphology and multigene phylogenetic analyses of ITS, LSU and RPB2. Phylogenetic analyses showed our strain clusters with K. europaea with moderate statistical support. Koorchaloma oryzae sp. nov. is morphologically similar to K. europaea, but it can be distinguished by the conidiophores and conidia, while ITS pairwise nucleotide comparison of these two species also revealed differences. Koorchaloma oryzae is compared with all known Koorchaloma species, and a key to Koorchaloma species is provided. Genealogical concordance phylogenetic species recognition analysis (PHI test) results of the new species and closely related species are also given.
Amphibambusa hongheensis sp. nov., a novel bambusicolous ascomycete from Yunnan, China
Amphibambusa hongheensis sp. nov. was collected from dead bamboo culms in Honghe County of Yunnan Province, China. The novel species is introduced based on the morpho-molecular approach. Morphologically, A. hongheensis fits well with Amphibambusa and is characterized by immersed, globose to subglobose ascomata, with protruding carbonaceous papilla, unitunicate, cylindrical to elongate fusiform, subsessile to short pedicellate asci with a J+, subapical ring, and fusiform, hyaline to pale brown, 1-septate ascospores, longitudinally striated, and surrounded by a thick mucilaginous sheath. Phylogenetic analyses of a concatenated ITS-LSU sequence dataset based on maximum-likelihood and Bayesian inference criteria revealed the phylogenetic affinity of A. hongheensis within Cainiaceae (Xylariales, Sordariomycetes). Amphibambusa hongheensis formed an independent subclade sister to A. bambusicola with moderate support (81% ML, 0.96 PP) and clustered with the genus Arecophila in Cainiaceae. Amphibambusa hongheensis is the second species accommodated in Amphibambusa and is reported from Yunnan, China, for the first time. Detailed description, illustration and updated phylogeny are provided.
Insight into the Systematics of Microfungi Colonizing Dead Woody Twigs of Dodonaea viscosa in Honghe (China)
Members of Dodonaea are broadly distributed across subtropical and tropical areas of southwest and southern China. This host provides multiple substrates that can be richly colonized by numerous undescribed fungal species. There is a severe lack of microfungal studies on Dodonaea in China, and consequently, the diversity, phylogeny and taxonomy of these microorganisms are all largely unknown. This paper presents two new genera and four new species in three orders of Dothideomycetes gathered from dead twigs of Dodonaea viscosa in Honghe, China. All new collections were made within a selected area in Honghe from a single Dodonaea sp. This suggests high fungal diversity in the region and the existence of numerous species awaiting discovery. Multiple gene sequences (non-translated loci and protein-coding regions) were analysed with maximum likelihood and Bayesian analyses. Results from the phylogenetic analyses supported placing Haniomyces dodonaeae gen. et sp. in the Teratosphaeriaceae family. Analysis of Rhytidhysteron sequences resulted in Rhytidhysteron hongheense sp. nov., while analysed Lophiostomataceae sequences revealed Lophiomurispora hongheensis gen. et sp. nov. Finally, phylogeny based on a combined dataset of pyrenochaeta-like sequences demonstrates strong statistical support for placing Quixadomyceshongheensis sp. nov. in Parapyrenochaetaceae. Morphological and updated phylogenetic circumscriptions of the new discoveries are also discussed.
Alloleptosphaeria shangrilana sp. nov. and first report of the genus (Leptosphaeriaceae, Dothideomycetes) from China
Alloleptosphaeria shangrilana, collected from dead wood of a dicotyledonous host in Shangri-La, China, is introduced as a new species based on evidence from morphological data and DNA sequence analyses. Maximum likelihood and Bayesian analyses of combined SSU, LSU and ITS sequence data were used to clarify the phylogenetic affinity of the new species. The new taxon is characterized by semi-immersed to superficial ascomata, a thick peridium, branched and septate pseudoparaphyses, cylindrical asci, muriform ascospores and overlapping uniseriate ascospores. Alloleptosphaeria species have been reported from England, Italy, Thailand and this is the first report of the genus in China. A detailed morphological description and analyses of the phylogenetic results are given for the new species. A key and synopsis table to the genus are also provided.
The Evolution of Life Modes in Stictidaceae, with Three Novel Taxa
Ostropales sensu lato is a large group comprising both lichenized and non-lichenized fungi, with several lineages expressing optional lichenization where individuals of the same fungal species exhibit either saprotrophic or lichenized lifestyles depending on the substrate (bark or wood). Greatly variable phenotypic characteristics and large-scale phylogenies have led to frequent changes in the taxonomic circumscription of this order. Ostropales sensu lato is currently split into Graphidales, Gyalectales, Odontotrematales, Ostropales sensu stricto, and Thelenellales. Ostropales sensu stricto is now confined to the family Stictidaceae, which includes a large number of species that are poorly known, since they usually have small fruiting bodies that are rarely collected, and thus, their taxonomy remains partly unresolved. Here, we introduce a new genus Ostropomyces to accommodate a novel lineage related to Ostropa, which is composed of two new species, as well as a new species of Sphaeropezia, S. shangrilaensis. Maximum likelihood and Bayesian inference analyses of mitochondrial small subunit spacers (mtSSU), large subunit nuclear rDNA (LSU), and internal transcribed spacers (ITS) sequence data, together with phenotypic data documented by detailed morphological and anatomical analyses, support the taxonomic affinity of the new taxa in Stictidaceae. Ancestral character state analysis did not resolve the ancestral nutritional status of Stictidaceae with confidence using Bayes traits, but a saprotrophic ancestor was indicated as most likely in a Bayesian binary Markov Chain Monte Carlo sampling (MCMC) approach. Frequent switching in nutritional modes between lineages suggests that lifestyle transition played an important role in the evolution of this family.
Loculosulcatispora thailandica gen. et sp. nov. (Sulcatisporaceae), saprobic on woody litter in Thailand
A new monotypic coelomycetous genus, Loculosulcatispora (type species L. thailandica) is introduced in Pleosporales from woody litter in Thailand. Phylogenetic analysis of combined non-translated loci (SSU, LSU, ITS) and protein-coding regions (tef1-α, rpb2) shows the genus is a distinct lineage in Sulcatisporaceae. Loculosulcatispora is distinguished from other genera in the family, by having 1-celled, oblong, hyaline, smooth-walled conidia with guttules. Comprehensive morphological descriptions and illustrations are provided for the new genus and species.