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Forty-one isolates representing 14 members of the ascomycete genus Capronia and 15 black yeasts belonging to the anamorph genera Exophiala, Cladosporium, Ramichloridium and Rhinocladiella w...

Despite a significant body of evidence in support of the close phylogenetic relationship of species of Capronia (Herpotrichiellaceae) and black yeasts belonging to or allied with the genus Exophiala questions concerning the taxonomic importance of features furnished by ascospore, stromal and anamorph characters have remained unanswered. In order to address these issues and to elucidate more fully relationships within the family, we have sequenced a portion of the nuclear large ribosomal RNA subunit (28S), the 5.8S gene, and the internal transcribed spacers (ITS1 and ITS2) of 15 species of Capronia and 19 black yeasts assigned to the form genera Cladosporium, Cladophialophora, Exophiala, Fonsecaea, Phaeococcomyces, Phialophora, Ramichloridium and Rhinocladiella. Cladistic analysis of these data confirmed the monophyly of the Herpotrichiellaceae but did not support the division of the genus Capronia on the basis of conidial ontogeny, pattern of ascospore septation, or the degree of stromal development. Homothallic species of Capronia with 8-spored asci, muriform ascospores and Exophiala anamorphs formed a well-supported lineage that included the medically important species Exophiala dermatitidis. Capronia mansonii and Capronia munkii, morphologically similar taxa isolated from the wood of Populus, were inferred as closely related but separate species. The clade comprising members of the Herpotrichiellaceae that possess Cladosporium-like and Phialophora anamorphs was also strongly supported. Available molecular evidence indicates that Dictyotrichiella semiimmersa and Phialophora americana are teleomorph and anamorph states of a single holomorph. Cladistic analysis also confirmed that the genera Cladophialophora and Ramichloridium are polyphyletic. The anamorphs of Capronia nigerrima and Dictyotmchiella semiimmersa are described and illustrated, and the combination Capronia semiimmersa is proposed.

Summary Temperate marine fungi are a distinct ecological group and differ from those found in tropical habitats, with the exception of a few cosmopolitan species. Sixty-two marine fungi were collected at San Juan Island, a temperate site, in 1994. The most frequently collected species were: Halosphaeria appendiculata, Monodictyspelagica, Halosarpheia trullifera, Ceriosporopsis halima and a new ascomycete. Eight records of Capronia ciliomaris were made, all on coniferous bark (probably Pseudosuga sp.). The fungi collected are compared with those previously reported from San Juan Island. The biogeography of marine fungi is discussed.

The taxonomy of selected species of Cap- ronia is discussed and illustrations are provided for Capronia mansonii, C. moravica and C. pulcherrima. Capronia mansonii, known only from the ex-type strain (CBS 101.67), is distinct from CBS 528.86, a second strain identified as this species. Capronia mo- ravica is shown to be a synonym of C. pilosella. The taxonomic position of the strain identified as C. pi- losella that possesses a Cladosporium-like anamorph is discussed. Anamorphs belonging to the black yeast genera Exophiala, Ramichloridium and Rhinocladiella are associated predominantly with members of the Herpotrichiellaceae. In contrast, species possessing Cladosporium-like asexual states and anamorphs be- longing to the form-genus Phialophora are found in distantly related ascomycete families. These latter an- amorphs are not, therefore, indicative of close, phy- logenetic relationships within the Ascomycotina. Cap- ronia hanliniana is excluded from the Herpotrichiel- laceae, and the combination Venturia hanliniana is proposed.

A method for the rapid, in vitro production of pseudothecia in species of Capronia is described. Mature pseudothecia of C. epimyces, C. mansonii, C. moravica, C. pinicola and an undescribed species of Capronia were obtained. Immature ascomata were ob? served for C. acutiseta and an isolate of Exophiala jean- selmei var. jeanselmei. Ascomatal initials and ascomata were not observed in the neotype strain of Hortaea werneckii and selected type strains of Exophiala. The role of anamorphs in the dispersal of species of Cap? ronia is discussed with reference to the occurrence of the yeast-like and hyphal states on natural substrata. The combination Capronia fungicola is proposed.