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The genus Metarhiziumhistorically refers to green-spored asexual insect pathogenic fungi. Through culturing and molecular methods, Metarhiziumhas been linked to Metacordycepssexual states. Historically fungal nomenclature has allowed separate names for the different life stages of pleomorphic fungi. However, with the move to one name for one fungus regardless of life stage, there is a need to determine which name is correct. For Metarhiziumthe situation is complicated by the fact that Metacordycepssexual states are interspersed among additional asexual genera, including Pochonia, Nomuraeaand Paecilomyces. Metarhiziumhas priority as the earliest available name, but delimiting the boundaries of this genus remains problematic. To clarify relationships among these taxa we have obtained representative material for each genus and established a molecular dataset of the protein-coding genes BTUB, RPB1, RPB2 and TEF. The resulting phylogeny supports Metarhiziumcombining the majority of species recognized in Metacordycepsas well as the green-spored Nomuraeaspecies and those in the more recently described genus Chamaeleomyces. Pochoniais polyphyletic, and we restrict the definition of this genus to those species forming a monophyletic clade with P. chlamydosporia, and the excluded species are transferred to Metapochoniagen. nov. It is our hope that this unified concept of sexual and asexual states in Metarhiziumwill foster advances in communication and understanding the unique ecologies of the associated species.

The anamorph genus Metarhiziumis composed of arthropod pathogens, several with broad geographic and host ranges. Members of the genus, including ‘‘M. anisopliaevar. frigidum’’ nomen nudum and Metarhizium flavoviride, have been used as biological insecticides. In a recent revision of the genus the variety ‘‘M. anisopliaevar. frigidum’’ was suggested to be a synonym of M. flavoviridebased largely on ITS sequence phylogenetic analysis. In this study we conducted morphological evaluations and multigene phylogenetic analyses with EF-1α, RPB1 and RPB2 for strains of M. flavovirideand ‘‘M. anisopliaevar. frigidum.’’ Included in these evaluations were the ex-type of M. flavoviridevar. flavovirideand what likely would be considered the ‘‘ex-type’ of the invalidly published taxon ‘‘M. anisopliaevar. frigidum’’. Based on morphological and molecular evidence we conclude that ‘‘M. anisopliaevar. frigidum’’ is distinct from M. flavovirideand the taxon M. frigidumsp. nov. is described.

During a recent collection trip to Barro Colorado Island, Panama, two species belonging to genus Ascopolyporus(Clavicipitaceae, Hypocreales) were collected. Species of Ascopolyporusare epibionts of their bamboo (Poaceae) host and long thought to be biotrophs of their plant hosts. However, based on morphological observations and phylogenetic evidence using large subunit ribosomal DNA data, we propose that genus Ascopolyporusis likely composed of pathogens of scale insects (Coccoideae, Homoptera). Phylogenetic analyses included Ascopolyporusspp. in a clade containing only entomopathogenic clavicipitaceous species (100% posterior probability), and the scale insect pathogen Hyperdermium bertoniiwas found to share the most recent common ancestor with the Ascopolyporusclade (98% posterior probability). In addition remnants of the scale insect were observed to be embedded within stromata during early stages of stroma development. Ascopolyporus philodendrussp. nov. was described and distinguished from the type species of the genus, A. polychrous,based on perithecial size, ascus size, plant host substrate and phylogenetic evidence. Furthermore subfamily Clavicipitoideae (Clavicipitaceae) was included and well supported in a single clade (100% posterior probability).