New and interesting chaetothyrialean fungi from Spain

Abstract

In the course of taxonomic studies on saprobic microfungi from Spain, several slow-growing, dematiaceous hyphomycetes were isolated from soil, submerged plant material and river sediments. Sixteen of these strains were identified as members of the ascomycete order Chaetothyriales on the basis of morphology and DNA sequence analyses of the internal transcribed spacer region and partial large subunit ribosomal RNA gene. These included three novel species (Cladophialophora pseudocarrionii, Cyphellophora chlamydospora, and Rhinocladiella amoena) and five interesting, little-known or clinically-relevant species (Cyphellophora suttonii, Exophiala aquamarina, E. lacus, E. radicis, and Rhinocladiella similis). In addition, Exophiala oligosperma, an emerging opportunistic fungus, was found for the first time in an aquatic freshwater environment (river sediments). Cladophialophora pseudocarrionii resembles C. carrionii in the branching pattern of its conidial chains, but differs from the latter species in its inability to grow at 30 A degrees C. Cyphellophora chlamydospora differs from other species of the genus in the absence of conidiation, producing only chlamydospores in vitro. Rhinocladiella amoena shows branched conidiophores similar to those of R. anceps, R. atrovirens, R. basitona and R. similis, but differs from them in conidial shape and size. The ex-type strain of Phialophora livistonae, included in the phylogenetic study, clustered with high statistical support with members of the genus Cyphellophora and is transferred to this genus.

In the course of taxonomic studies on saprobic microfungi from Spain, several slow-growing, dematiaceous hyphomycetes were isolated from soil, submerged plant material and river sediments. Sixteen of these strains were identified as members of the ascomycete order Chaetothyriales on the basis of morphology and DNA sequence analyses of the internal transcribed spacer region and partial large subunit ribosomal RNA gene. These included three novel species (Cladophialophora pseudocarrionii, Cyphellophora chlamydospora, and Rhinocladiella amoena) and five interesting, little-known or clinically-relevant species (Cyphellophora suttonii, Exophiala aquamarina, E. lacus, E. radicis, and Rhinocladiella similis). In addition, Exophiala oligosperma, an emerging opportunistic fungus, was found for the first time in an aquatic freshwater environment (river sediments). Cladophialophora pseudocarrionii resembles C. carrionii in the branching pattern of its conidial chains, but differs from the latter species in its inability to grow at 30 A degrees C. Cyphellophora chlamydospora differs from other species of the genus in the absence of conidiation, producing only chlamydospores in vitro. Rhinocladiella amoena shows branched conidiophores similar to those of R. anceps, R. atrovirens, R. basitona and R. similis, but differs from them in conidial shape and size. The ex-type strain of Phialophora livistonae, included in the phylogenetic study, clustered with high statistical support with members of the genus Cyphellophora and is transferred to this genus.