Phylogenetic inference by SSU-gene analysis of members of the Herpotrichiellaceae with special reference to human pathogenic species

The nearly complete 18S rDNA gene of 55 strains of black yeasts and their r elatives, all members of the ascomycete family Herpotrichiellaceae (order C haetothyriales), including 11 strains of the teleomorph genus Capronia, is sequenced. Recently studied black yeasts strains, as well as Ceramothyrium linnaeae (family Chaetothyrinceae) are included for comparison. All taxa st udied are represented by type or authentic strains, where available. Data a re analyzed with four different phy logenetic approaches. A low degree of r esolution of groups or clades is consistently found within the Herpotrichie llaceae. Relationships are best represented by a star-like rather than a tr ee-shaped structure. It thus seems probable that the Herpotrichiellaceae ar ose during a relatively short evolutionary period. In the few monophyletic groups that are recognizable, the Capronia teleomorphs are mostly found at the base, with anamorphs at higher positions in the clade. It is speculated that the family is in an active process of speciation, with accent on clon al reproduction. This is particularly the case with potentially human-patho genic taxa. The star-shaped representation of SSU sequence data hampers the distinction of (anamorph) genera on a phylogenetic basis; therefore curren t generic circumscriptions remain based on morphology. Foxia, Nadsoniella a nd Wangiella are treated as synonyms of Exophiala. New combinations in Exop hiala and Cladophialophora are proposed for species currently classified in ghost genera and for varieties that are sufficiently different to be recog nized at the species level. The ex-type strain of Rhinocladiella atrovirens has been found to represent a taxon phylogenetically remote from the remai ning strains known under that name. Examination of the dried type material (UPS) strongly suggests that a mix-up of strains has taken place.