Hagnosa longicapillata, gen. nov., sp. nov, is described and illustrated from wooden building materials collected in Hungary and from pure culture. This species has been collected exclusively from indoor environments, where it was quite common. The ascocarps develop in a thick layer of brown, woolly mats of mycelia. The ostiolar region of the perithecia is ornamented with a five-lobed, flower-shaped crown. Asci are four-spored; ascospores are dark brown, smooth, muriform, not constricted at the septa, and liberated mostly through crackings of the thin ascomatal wall. Apparently, ascospores are dispersed by the mechanical disturbance of the mycelial web. In the phylogenetic tree, Hagnosa samples were placed as a basal lineage, independently from the other family of Sordariomycetidae, with high support. To place Hagnosa in Sordariales, the new family, Hagnosaceae, is proposed.
Keywords: Hagnosa; indoor fungi; spore dispersal.