Unguiculariopsisstenospora (Cordieritidaceae, Leotiales, Ascomycota) is described as a new species. It is the first parasitic fungus on Celothelium lutescens, an ascomycete frequently found on bark of old Prunus avium trees in deciduous forests. Key words: Cordieritidaceae, lichenicolous fungi, new species, taxonomy. – Mycobiota of Germany.