Species diversity in Penicillium and Talaromyces from herbivore dung, and the proposal of two new genera of penicillium-like fungi in Aspergillaceae.

Abstract

Coprophilous fungi are saprotrophic organisms that show great diversity, mainly on herbivore dung. The physico-chemical characteristics of this peculiar substrate combined with the high level of fungal adaptation to different environmental conditions offer the perfect setting for discovering new taxa. This study focused on the species diversity of penicillium-like fungi isolated mainly from herbivore dung collected at different Spanish locations. From 130 samples, a total of 104 isolates were obtained, and 48 species were identified. Preliminary identifications were based on morphology and partial β-tubulin (tub2) gene sequences. Putative new taxa were characterized by a multi-gene sequencing analysis testing the tub2, the internal transcribed spacer rDNA (ITS), calmodulin (cmdA), and RNA polymerase II second largest subunit (rpb2) genes, and a detailed phenotypic study. Using this polyphasic approach and following the genealogical concordance phylogenetic species recognition (GCPSR) method, we propose the new genera Penicillago (for Penicillium nodositatum) and Pseudopenicillium (for Penicillium megasporum and P. giganteum) in the family Aspergillaceae, and 11 new species, including seven Penicillium, three Talaromyces and one Pseudopenicillium. A lectotype and epitype are designed for Penicillium nodositatum. Our results show that the species diversity of penicillium-like fungi on herbivore dung has not been widely studied and that this substrate seems to be a good reservoir of interesting Eurotialean fungi.