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Cyphellophora is a genus of black yeast-like fungi characterised by having simple phialides with multiseptate conidia.Judging from SSU and LSU data, Cyphellophora was found to be located in a well-supported clade within the Chaetothyriales comprising a number of species occurring on human skin and nail.Cyphellophora is phylogenetically close to Phialophora europaea, P.reptans and P.oxyspora, though morphologically these species produce single-celled phialoconidia rather than multiseptate ones.Pseudomicrodochium suttonii and P.fusarioides have dark colonies and phylogenetically fit in with Cyphellophora; the type species of Pseudomicrodochium, P.aciculare, has similar, septate conidia but has a hyaline thallus.In the present study, multilocus phylogenetic analyses were combined with morphology and physiology.Sequences of the internal transcribed spacer region, the DNA dependent RNA polymerase Ⅱ largest subunit and the partial beta tubulin gene were analysed for a set of 30 strains.Two novel species, Cyphellophora pauciseptata and Phialophora ambigua were discovered.Cyphellophora eucalypti was reduced to synonymy of C.guyanensis.The role of the studied fungi between colonization and infection of human skin was discussed.Putative virulence factors for these black yeast-like fungi were hypothesized to be the ability to assimilate monoaromatic hydrocarbons, to produce melanin pigments, and to tolerate the temperature of epidermal human skin.Rapid identification and typing methods Amplified Fragment Length Polymorphism and Rolling Circle Amplification were used to diagnose Cyphellophora and Relatives.In vitro activities of eight antifungal drugs against 81 isolates of Cyphellophora and its relatives in Phialophora were tested.The black yeast-like organisms are susceptible in vitro to the newer azoles and to micafungin, but show resistance to amphotericin-B, fluconazole and terbinafin.