International Association for Lichenology

Todd Widhelm

Todd Widhelm

The Committee for the Mason Hale award often has a difficult task, and this year has been no exception. All theses presented were of extraordinary quality, and it has been really gratifying to see research articles that are breaking new ground in lichenology.

We are very pleased to announce that the Mason Hale Award 2021 is given to Todd Widhelm, for his thesis entitled “Phylogenomic Systematics of Lichenized Fungi at Multiple Taxonomic Levels”. The thesis was completed at the Field Museum (Chicago), supervised by Roberta Mason-Gamer and Thorsten Lumbsch.

Todd Widhelm’s thesis has greatly enhanced our knowledge of the phylogenetic relationships of lichens, especially in the lobarioid clade of the family Peltigeraceae. The thesis goes into the depth of exciting topics in lichen evolution, including reticulate evolution; factors influencing speciation rates; and biogeographic patterns of species with disjunct distributions. Also, and very importantly, Todd’s thesis has been pioneering in applying cutting-edge high-throughput sequencing technologies (in particular RADseq and target enrichment sequencing) to lichen-forming fungi. These are cost-efficient methods developed to sample subsets of genome-scale data, and are suitable for phylogenomic studies at deep or shallow timescales.

The application of these technologies in lichens were initially hampered by methodological challenges, but Todd overcame them in his work. Todd’s studies are the first ones in lichen-forming fungi that use multi-gene data sets from 1) RADseq in a study of population genetics and biogeography of Pseudocyphellaria glabra (Widhelm, T. J., Grewe, F., Huang, J. P., Ramanauskas, K., Mason‐Gamer, R., Lumbsch, H. T. 2020. Using RADseq to understand the circum‐Antarctic distribution of a lichenized fungus, Pseudocyphellaria glabra. Journal of Biogeography 48. 10.1111/jbi.13983), and 2) target enrichment sequencing in a phylogenomic study of the former family Lobariaceae (Widhelm, T. J., F. Grewe, F., J. P. Huang, J. P., J. Mercado, J., B. Goffinet, B., R. Lücking, R., B. Moncada, B., R. Mason-Gamer, R., H. T. Lumbsch, H. T. 2019. Multiple historical processes obscure phylogenetic relationships in a taxonomically difficult group (Lobariaceae, Ascomycota). Scientific Reports 2019 9(1):8968).

We foresee that his thesis will become a reference point, opening great possibilities in the study of the phylogeny and evolution of other groups of lichenized fungi. Along these lines, we are glad to see some interesting new work led by Todd, published very recently (Widhelm, T.J., Grewe, F., Goffinet, B., Wedin, M., Goward, T., Coca, L. F., Distefano, I., Košuthová A., Lumbsch, H. T. 2021. Phylogenomic reconstruction addressing the Peltigeralean backbone (Lecanoromycetes, Ascomycota). Fungal Diversity.

Todd’s thesis represents a breakthrough in lichen systematics, and we look forward to his future research. Both the Committee and the IAL Council convey their warmest congratulations on his well-deserved success!

Ana Millanes (on behalf of the Hale Award Committee), Móstoles (Spain)