Abstract
An international survey of house dust collected from eleven countries using a modified dilution-to-extinction method yielded 7904 isolates. Of these, six strains morphologically resembled the asexual morphs of Aureobasidium and Hormonema (sexual morphs ?Sydowia), but were phylogenetically distinct. A 28S rDNA phylogeny resolved strains as a distinct clade in Dothideales with families Aureobasidiaceae and Dothideaceae their closest relatives. Further analyses based on the ITS rDNA region, p-tubulin, 28S rDNA, and RNA polymerase II second largest subunit confirmed the distinct status of this clade and divided strains among two consistent subclades. As a result, we introduce a new genus and two new species as Zalaria alba and Z. obscura, and a new family to accommodate them in Dothideales. Zalaria is a black yeast-like fungus, grows restrictedly and produces conidiogenous cells with holoblastic synchronous or percurrent conidiation. Zalaria microscopically closely resembles Hormonema by having only one to two loci per conidiogenous cell, but species of our new genus generally has more restricted growth. Comparing the two species, Z. obscura grows faster on lower water activity (aw) media and produces much darker colonies than Z. alba after 7 d. Their sexual states, if extant, are unknown.
Highlights
The average person in industrialized countries spends approximately 90 % of their time indoors (Höppe & Martinac 1998)
We are constantly exposed to fungal spores, fragments, and metabolites and their impact ranges from human health (Piecková & Jesenská 1999) as pathogens (De Hoog et al 2014, Garber 2001) or allergens (Aimanianda et al 2009, Karvala et al 2011, Tanno et al 2016) to food spoilage (Pitt & Hocking 2009, Samson et al 2010) or damage to building materials (Flannigan & Miller 2011)
Aureobasidium was distinguished based on its conidiogenous cells having multiple loci, in contrast to one or two loci in Hormonema (De Hoog & Yurlova 1994)
Summary
The average person in industrialized countries spends approximately 90 % of their time indoors (Höppe & Martinac 1998). Thambugala et al (2014) reviewed and re-evaluated the morphologically-based taxonomy of Dothideales known from culture, informed by a combined phylogeny of 28S rDNA, 18S rDNA and ITS They accepted two families, synonymising the often-accepted Dothioraceae (e.g. Barr 2001) with Dothideaceae, DV ¿UVW SURSRVHG E\ 9RQ $U[ 0OOHU and introducing Aureobasidiaceae for Aureobasidium and FORVHO\ UHODWHG JHQHUD 7KH SRO\WKHWLF PRUSKRORJLFDO GH¿QLWLRQV provided by Thambugala et al (2014) did not identify unique diagnostic characters among the sexual or asexual morphs in either family. Aureobasidium was distinguished based on its conidiogenous cells having multiple loci (synchronous conidiogenesis), in contrast to one or two loci in Hormonema (De Hoog & Yurlova 1994) These characters DUH GLI¿FXOW WR GHWHFW DQG DUH EHVW REVHUYHG DORQJ K\SKDH DW the growing margin of the colony.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
