Studies in Mycology No. 2

The genus Talaromyces is re-defined. It is restricted to species producing asci in chains. The genus is divided into 4 sections, Talaromyces, Emersonii, Thermophila and Purpurea, wich are primarily based on their conidial states. Descriptions, figures and scanning electron micrographs are given of the species belonging to the genus. The species, transferred by Benjamin and Udagawa from the imperfect genus Penicillium to the perfect genus Talaromyces are validated by providing latin diagnoses. Two species of Gymnoascus, G. flavus Klöcker and G. luteus Sacc. and three species of Arachniotus, A. trachyspermus Shear, A. intermedius Apinis and A. purpureus Müller & Pacha-Aue are transferred to Talaromyces. Two new species, T. byssochlamydoides and T. udagawae, and two new varieties, T. flavus var. macrosporus and T. helicus var. major are described. A key to the genera with Paecilomyces or Penicillium conidial states and to the sections of Talaromyces is given. Species are keyed out in each section and in an additional key based on ascospore characters. A new series of Penicillium, the Penicillium cylindrosporum-series is proposed.