Scopulariopsis and scopulariopsis-like species from indoor environments

Abstract

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.