Microascaceae from the Marine Environment, with Descriptions of Six New Species

Most reported members of Microascaceae that have been reported originate from the terrestrial environment, where they act as saprobes or plant pathogens. However, our understanding of their species diversity and distribution in the marine environment remains vastly limited, with only 22 species in nine genera having been reported so far. A survey of the fungal diversity in intertidal areas of China's mainland has revealed the discovery of several Microascaceae strains from 14 marine algae and 15 sediment samples. Based on morphological characteristics and LSU-ITS-tef1-tub2 multilocus phylogeny using Bayesian inference and maximum likelihood methods, 48 strains were identified as 18 species belonging to six genera. Among these, six new species were discovered: Gamsia sedimenticola, Microascus algicola, M. gennadii, Scedosporium ellipsosporium, S. shenzhenensis, and S. sphaerospermum. Additionally, the worldwide distribution of the species within this family across various marine habitats was briefly reviewed and discussed. Our study expands the knowledge of species diversity and distribution of Microascaceae in the marine environment.

Cephalotrichum and related synnematous fungi with notes on species from the built environment

A recent taxonomic revision of Microascaceae with an emphasis on synnematous fungi enabled re-identification of previously isolated indoor strains of Cephalotrichum. All available Cephalotrichum strains from the culture collection of the Westerdijk Institute were studied, 20 originating from the built environment. Phylogenetic relationships were inferred from DNA sequence data from the internal transcribed spacer 1 and 2 and intervening 5.8S nrDNA (ITS), and parts of β-tubulin (tub2) and translation elongation factor 1-α (tef1) genes. Additionally, herbarium material of 14 Cephalotrichum species described from soil in China was studied, and the taxonomy of C. album, not considered in recent revisions, was reevaluated. Sixteen phylogenetic species in Cephalotrichum are distinguished, five described as new species: C. domesticum, C. lignatile, C. telluricum, C. tenuissimum and C. transvaalense. Five Cephalotrichum species occur in the built environment: C. domesticum, C. gorgonifer (formerly known as Trichurus spiralis), C. microsporum, C. purpureofuscum, and C. verrucisporum. Based on the number of isolates, C. gorgonifer (nine strains) is the most common indoor species. The study of the Chinese herbarium material resulted in the acceptance of three additional Cephalotrichum species: C. casteneum, C. ellipsoideum, and C. spirale. Four species are considered nomena dubia (C. cylindrosporum, C. macrosporum, C. ovoideum, and C. robustum), five are placed in synonymy with other Cephalotrichum species (C. acutisporum, C. inflatum, C. longicollum, C. oblongum, C. terricola) and one species, C. verrucipes, is probably a synonym of Penicillium clavigerum. Cephalotrichum columnare, former Doratomyces columnaris, is transferred to Kernia. Cephalotrichum album, formerly known as Doratomyces putredinis, is transferred to Acaulium and redescribed.

Scopulariopsis and scopulariopsis-like species from indoor environments

Scopulariopsis-like species are often reported from the indoor environment, as well as from clinical samples. The lack of type isolates and thorough phylogenetic studies in the Microascaceae hampered the correct identification of these isolates. Based on recent phylogenetic studies, which resulted in multiple name changes, the aim is to molecularly identify the Scopulariopsis and scopulariopsis-like species which occur in the indoor environment and give an overview of the current species in these genera and their habitats. Strains from the CBS culture collection were supplemented with almost 80 indoor strains of which the internal transcribed spacer 1 and 2 and intervening 5.8S nrDNA (ITS), beta-tubulin (tub2) and translation elongation factor 1-alpha (tef1) gene regions were sequenced for phylogenetic inference. The multi-gene phylogenies recognise 33 Microascus species and 12 Scopulariopsis species and showed that the recently established genus Fuscoannellis, typified by Scopulariopsis carbonaria, should be synonymized with the genus Yunnania. Seven new Microascus species, four new Scopulariopsis species, and one new Yunnania species, are described, and a new name in Microascus and two new name combinations (one in Microascus, and one in Yunnania) are proposed. In the indoor environment 14 Microascus species and three Scopulariopsis species were found. Scopulariopsis brevicaulis (22 indoor isolates) and Microascus melanosporus (19 indoor isolates) are the most common indoor species, in number of isolates, followed by M. paisii (8 indoor isolates) and S. candida (7 indoor isolates). A genus phylogeny based on the ITS, tef1 and the large subunit 28S nrDNA (LSU) of the type or representative isolates of all here recognised species is provided depicting all species habitats. No correlation between phylogenetic relationship and habitat preference could be observed. Ten species which are found indoor are also found in relation with human-derived samples. A table showing recent name changes and a key to common species of Scopulariopsis and scopulariopsis-like genera found indoors is included.

Redefining Microascus, Scopulariopsis and allied genera

The genera Microascus and Scopulariopsis comprise species commonly isolated from soil, decaying plant material and indoor environments. A few species are also recognised as opportunistic pathogens of insects and animals, including humans. In the past, the taxonomy of these fungi has been based on morphology only. With the aim to clarify the taxonomy and phylogeny of these fungi, we studied a large set of clinical and environmental isolates, including the available ex-type strains of numerous species, by means of morphological, physiological and molecular analyses. Species delineation was assessed under the Genealogical Phylogenetic Species Recognition (GCPSR) criterion using DNA sequence data of four loci (ITS region, and fragments of rDNA LSU, translation elongation factor 1-α and β-tubulin). The genera Microascus and Scopulariopsis were found to be separated in two distinct lineages. The genus Pithoascus is reinstated and the new genus Pseudoscopulariopsis is erected, typified by P. schumacheri. Seven new species of Microascus and one of Scopulariopsis are described, namely M. alveolaris, M. brunneosporus, M. campaniformis, M. expansus, M. intricatus, M. restrictus, M. verrucosus and Scopulariopsis cordiae. Microascus trigonosporus var. macrosporus is accepted as a species distinct from M. trigonosporus. Nine new combinations are introduced. Microascus cinereus, M. longirostris, P. schumacheri and S. flava are neotypified. A table summarising the morphological features of the species treated and identification keys for each genus are provided.